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Cyclopentadienone Formation from #,#-Unsaturated Cyclopentenones and Its Application in Diels-Alder Reactions Xiangwen Kong, Shuang Yang, Fang Yu, Laxmaiah Vasamsetty, Jian Liu, Shuhua Liu, Xiaozhi Liu, and Xinqiang Fang J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.8b01150 • Publication Date (Web): 05 Jul 2018 Downloaded from http://pubs.acs.org on July 6, 2018

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The Journal of Organic Chemistry

Cyclopentadienone Formation from β,γ-Unsaturated Cyclopentenones and its Application in Diels-Alder Reactions Xiangwen Kong,† Shuang Yang,‡ Fang Yu,‡ Laxmaiah Vasamsetty,‡ Jian Liu,‡ Shuhua Liu,*,§ Xiaozhi Liu*,† and Xinqiang Fang*,‡ †

Liaoning University, Shenyang, Liaoning 110036, China

‡

State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian

Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350100, China §

Shandong Analysis and Test Center, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, China

Abstract:

We report that α-acyloxy-β,γ-unsaturated cyclopentenones were used as

starting substrates to make various trisubstituted cyclopentadienones.The substrates are easily available in one step from our previously developed protocol, and the potential of this cyclopentadienone formation method was demonstrated in a series of Diels-Alder reactions, forming dimerization products, dimethyl phthalate derivatives, and polyaryl benzene compounds.

INTRODUCTION Cyclopentadienones (CPDs) are a family of fascinating molecules with broad applications in chemical synthesis, material science, and biological studies.1 They have

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been used in annulation reactions to release aromatic rings with multiple substituents,2 and employed as ligands to form a range of coordination complexes, which can catalyze a series of valuable transformations.3 Furthermore, cyclopentadienones have been used to make biologically active natural products, including manzamenone A, chamaecypanone C, and hirsutic acid.4 Additionally, they have also been utilized to make polymer-related materials.5

Scheme 1. Selected Methods to Make Polysubstituted Cyclopentadienones

Although various methods have been used to make CPDs, the access to these compounds with multiple different substituents remains challenging. As shown in Scheme 1a, the condensation of propanone derivatives with 1,2-diketones is widely used to make symmetrical CPDs, but it is problematic for the synthesis of unsymmetric ones because of the difficulty in controlling the regioselectivity.6 The transition-metalcatalyzed [2+2+1] annulations using alkynes and CO will also meet the same


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regioselectivity problem and the successful reports are mainly limited in intramolecular reactions.7 An elegant rhodium(I)-catalyzed [3+2] cycloaddition of cyclopropenones and alkynes was reported by the Wender group, and high regioselectivity could also be realized when substrates with different substituents were used (Scheme 1b).8 Despite these advances, elimination reactions using unsaturated cyclopentanones remain to be a reliable strategy to afford differently substituted CPDs (Scheme 1c). In this context, Depuy and co-workers reported the application of 4-bromocyclopentenone as CPD precursor under basic conditions.9 4-Sulfonyloxycyclopentenone was used by Gaviña to produce CPDs.10 Later, Harmata et al. found that 2-bromocyclopentenones could also be used to realize the same purpose.11 Furthermore, Porco and co-workers have developed elegant oxidative or rhodium-catalyzed dehydrogenation protocol for the conversion of 2,4-diarylcyclopentenones to the corresponding 2,4-diaryl CPDs, and using this method, they could achieve the total synthesis of chamaecypanone C and its analogues.12 The limitation of the elimination method is that, in some cases, multiple steps are necessary to get the unsaturated cyclopentanones and thus limit the further applications of this protocol. Moreover, although α,β-unsaturated cyclic ketones have been exploited extensively, the potential of β,γ-unsaturated ones as CPD precursor has been less studied.13 Here we report a protocol allowing the access to trisubstituted CPDs from α-acyloxyβ,γ-unsaturated cyclic ketones. Noteworthy is that such type of starting substrates can be synthesized in one step using our recently developed method under particularly mild conditions, and all three substituents can be changed at will.14 Furthermore, the reaction displays excellent regioselectivity in Diels-Alder reactions. RESULTS AND DISCUSSION Our discovery derived from a reaction design using the diene moiety within 1a to undergo Diels-Alder reactions (Table 1). However, no desired product was detected under thermal conditions, and a formal dimerization product 2a was obtained. We reasoned that such a relatively complicated molecule should be formed from cyclopentadienone 1’, which was derived from 1 via decarboxylative elimination. Considering the convenience and substituent diversity of this method, and the importance



of CPDs, we further investigated the applications of this transformation. As shown in Table 1, β,γ-unsaturated cyclic ketone 1a, bearing two phenyl groups and a styryl group, Table 1. Substrate Scope of Dimerizationa

a

Reaction conditions: 1 (0.4 mmol), 1,2-dichlorobenzene (0.5 mL), argon protection. All yields were of

isolated products based on 1.


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could undergo the dimerization smoothly to afford 2a in moderate yield (Table 1, 2a). Moreover, the reaction could tolerate the introduction of electron-withdrawing or electron-donating groups such as 4-chloro and 4-methyl groups into the styryl moiety, producing 2b and 2c in 87% and 66% yields, respectively (Table 1, 2b and 2c). Furthermore, we were pleased to find that the replacement of phenyl group at R3 position with 4-methyl phenyl group had no influence on the outcome, delivering 2d in 64% yield (Table 1, 2d). To our delight, the variation of both R1 and R3 units through introducing chloro and methoxy groups resulted no effect on the reaction, leading to the formation of 2e in 69% yield (Table 1, 2e). Additionally, when R2 was a phenyl group, the corresponding annulation product was generated in 54% yield (Table 1, 2f). It is interesting that when 1g, a substrate bearing three differently substituted phenyl groups, was

tested,

the

corresponding

dimerization

product

could

undergo

further

decarbonylation reaction to release the bicyclic product 2g in 85% yield, possibly because of the relatively lower stability of the corresponding dimerization compound under the reaction conditions. Noteworthy is that the structure and configuration of 2b was confirmed via X-ray crystallographic analysis (Figure 1).

O

H

Ph O Ph Cl

Ph

Ph

2b

Cl

Figure 1. X-ray single crystal structure of 2b (50% probability level). Having tested the scope of dimerization, we wondered the possibility of trapping the CPD intermediate via other types of dienophiles such as dimethyl acetylenedicarboxylate. The process involves a Diels-Alder reaction to form intermediate 3’, and the following decarbonylation will allow access to dimethyl phthalate derivatives. Pleasingly, our test using 1a and dimethyl acetylenedicarboxylate under the same conditions as used in Table 1 led to the formation of 3a in 90% yield, a phthalate compound with multiple substituents (Table 2, 3a). Then we checked the influence of introducing substituents into



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R2 and R3 moieties, respectively, and it proved that the reaction proceeded smoothly to afford 3b and 3c in excellent 95% and 99% yields, respectively (Table 2, 3b and 3c). Moreover, substrate 1e, with two different substituents, could release the corresponding ester 3d in 93% yield (Table 2, 3d). Furthermore, substrates 1f and 1h were found to be tolerated under the reaction conditions, allowing the access to 3e and 3f with three aryl substituents in excellent yields (Table 2, 3e and 3f). Table 2. Substrate Scope of Dimethyl Phthalate Formationa R3

MeO2C

OCOR4

CO2Me

170 °C, 2 h 1,2-dichlorobenzene

R2

R1

R3

O

O

R3

MeO2C MeO2C

R1

3'

1

R2

MeO2C

R2

MeO2C

R1 3 Cl

O Ph

O Ph Ph

OCOPh

MeO2C

OCOPh

Ph

MeO2C

MeO2C

Ph 1a

1b

3a 90% yield

Me

Ph

1d

3b 95% yield

OMe

OMe Ph

Ph OCOPh

Cl

O

Me O

Ph

MeO2C

Ph

OCOPh

MeO2C

Ph

MeO2C 3c 99% yield

MeO2C MeO2C

1e

Cl

3d 93% yield

Cl

Me O Ph OCOPh Ph

Ph 1f

a

Me

O MeO2C

OCOPh

MeO2C

Ph

3e 99% yield

Ph 1h

MeO2C MeO2C 3f 92% yield

Reaction conditions: 1 (0.4 mmol), dimethyl acetylenedicarboxylate (4 mmol), 1,2-dichlorobenzene (0.5

mL), argon protection. All yields were of isolated products based on 1.


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Then we planned to expand the application of this protocol to the synthesis of polyaryl arenes, a type of molecule with wide utility in material sciences, including liquid crystals, microporous organic solids, molecular rotors, and molecular wires.15 We were glad to see that the reaction of 1f with 1,2-diphenylethyne afforded pentaphenyl benzene 4a in 36% yield (Table 3, 4a). Introduction of ethyl group into the phenyl ring at R1 unit had no obvious effect on the outcome, leading to the formation of 4b in 35% yield (Table 3, 4b). Similarly, pentaphenyl benzene 4c, with a 4-methyl substituent, was formed in 32% yield (Table 3, 4c). Replacement of the phenyl group at R3 unit with 4-methyl phenyl group had no influence on the result (Table 3, 4d). Moreover, 4e, with a 4-methoxyl phenyl group at R3 position, could also be obtained (Table 3, 4e). Then we surveyed a series symmetrical internal diaryl acetylenes with different substituents, such as Cl, F, and Br. The reaction afforded 4f, 4g, and 4h in various yields (Table 3, 4f, 4g, and 4h). We also tested unsymmetrical acetylene and the penta-aryl benzenes with five differently substituted phenyl rings were formed in a 1.7:1 mixture (Table 3, 4i and 4j). Table 3. Substrate Scope of Polyaryl Benzene Formationa




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a

Reaction conditions: 1 (0.4 mmol), alkyne (4 mmol), 1,2-dichlorobenzene (0.5 mL), argon protection. All

yields were of isolated products based on 1. bTwo annulation products were obtained with 1.7:1 ratio.

Scheme 2. Product Derivatization O NaBH4

H Ph

Ph

OH H

MeOH/1,4-dioxane rt, 1 h

Ph

2a Ph

H

Ph OH H Ph H

LiAlH4

HO

THF, rt, 1 h

Ph

5a > 20:1 dr 99% yield

Ph

6a > 20:1 dr 80% yield

As shown in Scheme 2, the selective reduction of 2a using NaBH4 could be realized, affording 5a in 99% yield with excellent diastereoselectivity. Furthermore, a global reduction of the two carbonyl groups in 2b could be achieved by LiAlH4, releasing 6a in 80% yield with > 20:1 dr. Notably, different stereoselectivity of ketone reduction was observed compared to the corresponding NaBH4 reduction, and this result was confirmed by NOESY sepctra analysis of 5a and 6a. Furthermore, diester 3a could be reduced to diol 7a in 54% yield, and the next dehydration of 7a resulted in dihydroisobenzofuran 8a in 53% yield. We also tested the possibility of “one-pot” reaction starting from alkynyl diketone and phenyl vinyl ketone without isolation of the reaction mixture of the first step. As illustrated in Scheme 3, the final dimerization product 2a can be formed in 50% yield, which is comparable to the corresponding result via stepwise approach. Scheme 3. “One-pot” experiment



Scheme 4. Mechanistic Experiments

Mechanistically, using 1b’ as the starting material, we found that at lower temperature and within shorter time, an intermediate compound 2b’ was formed in 83% isolated yield (Scheme 4). The further reaction using 2b’ under similar conditions in Table 1 resulted in the formation of 2b. This experiment indicated that the reaction might proceed first via a [3,3]-rearrangement to form 2b’, then the elimination of aromatic acid led to the corresponding CPD intermediate, which would undergo various Diels-Alder reactions. CONCLUSION In summary, we have disclosed a method allowing access to various trisubstituted CPDs using α-acyloxy-β,γ-unsaturated cyclic ketones. Such type of starting material are easily available from our recently developed method in one step, and the utilities of this method have been demonstrated in CPD-mediated synthesis of a series of value-added molecules via Diels-Alder reactions, such as dimerization, formation of dimethyl phthalate derivatives, and synthesis of polyaryl benzene compounds. EXPERIMENTAL SECTION Commercially available materials were used as received, unless otherwise noted, all reactions and manipulations involving air- or moisture- sensitive compounds were performed using standard Schlenk techniques. Proton nuclear magnetic resonance (1H NMR) spectra were recorded on a 400 MHz spectrometer. Carbon nuclear magnetic


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resonance (13C NMR) spectra were recorded on a 100 MHz spectrometer. In some cases carbon peaks are overlapped, resulting in less carbon signals than expected. High resolution mass spectral analysis (HRMS) was performed on a LTQ Orbitrap mass spectrometer. Synthesis of cyclopentenones. All starting materials were prepared from the reactions of allyl ketones with alkynyl 1,2-diketones under basic conditions according to the literature procedure.13 Substrates 1a-1f are known compounds.13 3-(4-Ethylphenyl)-1-(4-methoxyphenyl)-5-oxo-2-(p-tolyl)cyclopent-2-en-1-yl

benzoate

(1g): Yellow solid (125.7 mg, 25% yield). Mp 60−63 °C. 1H NMR (400 MHz, CDCl3) δ 7.98−7.96 (m, 2H), 7.57−7.53 (m, 1H), 7.44−7.36 (m, 4H), 7.32−7.28 (m, 2H), 7.23 (d, J = 8.4 Hz, 2H), 6.92−6.87 (m, 4H), 6.84−6.82 (m, 2H), 3.79 (s, 3H), 3.75 (d, J = 18.2 Hz, 1H), 3.30 (d, J = 22.4 Hz, 1H), 2.68 (q, J = 7.6 Hz, 2H), 2.21 (s, 3H), 1.26 (t, J = 7.6 Hz, 3H);

13

C NMR (100 MHz, CDCl3) δ 203.0, 166.4, 165.2, 159.6, 144.0, 139.9, 139.1,

138.8, 133.3, 131.3, 130.6, 130.1, 129.7, 129.4, 128.9, 128.6, 128.5, 124.9, 123.3, 113.9, 86.8, 55.3, 52.1, 28.5, 21.4, 15.5; HRMS (ESI-ion trap), m/z: [M+H]+ calcd for C34H30O4H+ 503.2217, found 503.2213; IR (KBr thin film, cm−1): ν 2967, 2930, 2050, 1715, 1507, 1345, 1283, 1249, 1167, 1104, 1025, 829. 5-Oxo-2,3-diphenyl-1-(p-tolyl)cyclopent-2-en-1-yl benzoate (1h): Yellow solid (200.1 mg, 45% yield). Mp 66−68 °C. 1H NMR (400 MHz, CDCl3) δ 7.93 (d, J = 7.0 Hz, 2H), 7.58−7.50 (m, 3H), 7.39−7.34 (m, 4H), 7.25 (s, 5H), 7.09−7.02 (m, 5H), 3.95 (d, J = 22.4 Hz, 1H), 3.50 (d, J = 22.4 Hz, 1H), 2.38 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 206.6, 165.3, 139.0, 138.7, 136.8, 135.6, 134.1, 133.42, 133.35, 130.0, 129.9, 129.5, 129.4, 128.6, 128.5, 128.4, 128.3, 127.9, 125.7, 90.5, 44.1, 21.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C31H24O3H+ 445.1798, found 445.1797; IR (KBr thin film, cm−1): ν 1763, 1706, 1646, 1556, 1414, 1345, 1283, 1098, 1016, 778. 3-(4-Ethylphenyl)-5-oxo-1,2-diphenylcyclopent-2-en-1-yl benzoate (1i): Yellow solid (192.6 mg, 42% yield). Mp 77−79 °C. 1H NMR (400 MHz, CDCl3) δ 8.02−8.00 (m, 2H), 7.77−7.75 (m, 2H), 7.57−7.49 (m, 3H), 7.45−7.39 (m, 3H), 7.35−7.32 (m, 2H), 7.16−7.09 (m, 7H), 4.05 (d, J = 22.4 Hz, 1H), 3.58 (d, J = 22.4 Hz, 1H), 2.66 (q, J = 7.6 Hz, 2H),



1.26 (t, J = 7.6 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ 206.5, 165.2, 144.8, 139.0, 136.4, 135.9, 134.3, 133.4, 132.6, 129.8, 129.4, 129.3, 129.2, 128.7, 128.53, 128.50, 128.3, 128.0, 127.8, 125.7, 90.6, 44.0, 28.7, 15.4; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C32H26O3H+ 459.1955, found 459.1958; IR (KBr thin film, cm−1): ν 2955, 1763, 1649, 1547, 1414, 1280, 1104, 1027, 826, 735, 707. 5-Oxo-1,3-diphenyl-2-(p-tolyl)cyclopent-2-en-1-yl benzoate (1j): Yellow solid (106.7 mg, 24% yield). Mp 51−53 °C. 1H NMR (400 MHz, CDCl3) δ 8.02 (d, J = 7.2 Hz, 2H), 7.75 (d, J = 7.2 Hz, 2H), 7.58−7.48 (m, 3H), 7.44−7.41 (m, 5H), 7.34−7.29 (m, 3H), 6.96−6.88 (m, 4H), 4.01 (d, J = 22.4 Hz, 1H), 3.56 (d, J = 22.4 Hz, 1H), 2.21 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 206.5, 165.2, 138.6, 137.6, 136.6, 136.4, 135.7, 133.4, 130.9, 129.9, 129.34, 129.26, 129.2, 129.1, 128.7, 128.52, 128.50, 128.3, 125.7, 90.4, 44.1, 21.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C31H24O3H+ 445.1798, found 445.1801; IR (KBr thin film, cm−1): ν 1715, 1663, 1558, 1550, 1516, 1510, 1414, 1272, 1101, 1019, 780, 729. General procedure for the Diels-Alder reaction. To a 5 mL, two-necked, oven-dried flask was added cyclopentenone 1a (182.6 mg, 0.4 mmol) and 1,2-dichlorobenzene (0.5 mL). The flask was then sealed, vacuumized and refilled with dry argon. Then the reaction was kept heating at 170 oC for 1.5 h under microwave with an external surface sensor. Then the reaction mixture was cooled to room temperature and the solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel with petroleum ether/ethyl acetate (10:1 v/v) as eluent to afford the product of 2a as a yellow solid (68.2 mg, 51% yield). 2,3a,5,7-Tetraphenyl-3,6-di((E)-styryl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoindene-1,8dione (2a): Yellow solid (68.2 mg, 51% yield). Mp 159−160 °C. 1H NMR (400 MHz, CDCl3) δ 7.64−7.60 (m, 4H), 7.44−7.30 (m, 11H), 7.23−7.04 (m, 13H), 6.86 (d, J = 16.5 Hz, 1H), 6.76 (d, J = 7.2 Hz, 2H), 6.57 (d, J = 16.4 Hz, 1H), 6.50 (d, J = 16.4 Hz, 1H), 6.00 (d, J = 16.5 Hz, 1H), 4.71 (s, 1H), 3.73 (s, 1H);

13

C NMR (100 MHz, CDCl3) δ

203.3, 198.3, 163.6, 146.9, 142.3, 140.6, 138.7, 137.6, 137.4, 136.8, 136.0, 134.8, 133.0, 130.9, 130.7, 130.0, 129.9, 129.6, 129.3, 128.62, 128.58, 128.54, 128.45, 128.3, 128.2,


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127.9, 127.8, 127.6, 127.2, 126.7, 126.2, 122.5, 119.1, 66.9, 58.6, 58.5, 57.2; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C50H36O2H+ 669.2788, found 669.2770; IR (KBr thin film, cm−1): ν 1868, 1774, 1734, 1700, 1655, 1635, 1558, 1544, 1507, 1419, 1101, 1010, 780. 3,6-Bis((E)-4-chlorostyryl)-2,3a,5,7-tetraphenyl-3a,4,7,7a-tetrahydro-1H-4,7methanoindene-1,8-dione (2b): Yellow solid (128.4 mg, 87% yield). Mp 127−129 °C. 1H NMR (400 MHz, CDCl3) δ 7.64−7.60 (m, 4H), 7.44−7.30 (m, 11H), 7.20−7.07 (m, 9H), 6.99 (d, J = 7.9 Hz, 2H), 6.83 (dd, J = 16.5, 1.8 Hz, 1H), 6.68 (d, J = 7.4 Hz, 2H), 6.54−6.44 (m, 2H), 5.95 (dd, J = 16.5, 1.3 Hz, 1H), 4.70 (d, J = 2.7 Hz, 1H), 3.74 (d, J = 1.9 Hz, 1H);

13

C NMR (100 MHz, CDCl3) δ 203.3, 198.0, 163.2, 147.2, 142.1, 139.2,

139.0, 137.3, 135.7, 135.4, 135.1, 134.7, 134.4, 133.6, 132.8, 130.7, 130.6, 129.9, 129.7, 128.8, 128.74, 128.69, 128.66, 128.6, 128.4, 128.3, 128.0, 127.84, 127.77, 127.7, 126.2, 123.0, 119.5, 66.9, 58.6, 58.4, 57.2; HRMS (EI-ion trap), m/z: M+ calcd. for C50H34Cl2O2+ 736.1930, found 736.1950; IR (KBr thin film, cm−1): ν 1839, 1774, 1740, 1703, 1658, 1644, 1547, 1527, 1414, 1343, 1087, 1016, 789. 3,6-Bis((E)-4-methylstyryl)-2,3a,5,7-tetraphenyl-3a,4,7,7a-tetrahydro-1H-4,7methanoindene-1,8-dione (2c): Yellow solid (92.0 mg, 66% yield). Mp 89−91 °C. 1H NMR (400 MHz, CDCl3) δ 7.64−7.59 (m, 4H), 7.42−7.27 (m, 11H), 7.21 (d, J = 7.3 Hz, 2H), 7.11−6.92 (m, 9H), 6.82 (d, J = 16.5 Hz, 1H), 6.66 (d, J = 7.9 Hz, 2H), 6.55 (d, J = 16.4 Hz, 1H), 6.46 (d, J = 16.4 Hz, 1H), 5.98 (d, J = 16.5 Hz, 1H), 4.69 (s, 1H), 3.72 (s, 1H), 2.29 (s, 3H), 2.27 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 203.3, 198.4, 163.9, 146.5, 142.5, 140.7, 139.7, 138.2, 137.9, 137.8, 136.7, 134.9, 134.7, 133.3, 133.1 131.1, 130.7, 130.0, 129.6, 129.3, 129.2, 128.63, 128.55, 128.5, 128.4, 128.2, 127.7, 127.6, 127.2, 126.7, 126.2, 121.6, 118.2, 66.9, 58.5, 57.2, 21.5, 21.4; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C52H40O2H+ 697.3101, found 697.3101; IR (KBr thin film, cm−1): ν 1871, 1791, 1768, 1712, 1695, 1666, 1564, 1544, 1453, 1411, 1022, 786. 3a,5-Diphenyl-3,6-di((E)-styryl)-2,7-di-p-tolyl-3a,4,7,7a-tetrahydro-1H-4,7methanoindene-1,8-dione (2d): Yellow solid (89.2 mg, 64% yield). Mp 150−153 °C. 1H NMR (400 MHz, CDCl3) δ 7.61 (d, J = 7.7 Hz, 2H), 7.53 (d, J = 8.0 Hz, 2H), 7.41 (t, J =



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7.5 Hz, 2H), 7.32−7.28 (m, 2H), 7.25−7.03 (m, 18H), 6.88 (d, J = 16.5 Hz, 1H), 6.77 (d, J = 7.1 Hz, 2H), 6.55 (d, J = 2.4 Hz, 1H), 6.09 (d, J = 16.5 Hz, 1H), 4.70 (s, 1H), 3.71 (s, 1H), 2.39 (s, 3H), 2.36 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 203.5, 198.7, 163.1, 147.0, 142.5, 140.1, 138.7, 138.5, 137.6, 137.5, 137.2, 136.6, 136.1, 134.9, 130.4, 130.0, 129.8, 129.5, 129.3, 129.2, 129.0, 128.6, 128.5, 128.43, 128.41, 128.0, 127.8, 127.7, 127.6, 127.2, 126.7, 126.2, 122.7, 119.3, 66.7, 58.6, 58.5, 57.2, 21.5, 21.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C52H40O2H+ 697.3101, found 697.3101; IR (KBr thin film, cm−1): ν 2924, 2842, 1788, 1692. 1644, 1561, 1516, 1416, 1252, 1167, 1096, 789. 3a,5-Bis(4-chlorophenyl)-2,7-bis(4-methoxyphenyl)-3,6-di((E)-styryl)-3a,4,7,7atetrahydro-1H-4,7-methanoindene-1,8-dione (2e): Yellow solid (110.1 mg, 69% yield). Mp 71−74 °C. 1H NMR (400 MHz, CDCl3) δ 7.52−7.49 (m, 4H), 7.37 (d, J = 8.5 Hz, 2H), 7.25−7.16 (m, 8H), 7.10−7.01 (m, 6H), 6.96−6.90 (m, 4H), 6.78−6.73 (m, 3H), 6.47 (s, 2H), 6.08 (d, J = 16.5 Hz, 1H), 4.51 (s, 1H), 3.82 (s, 3H), 3.80 (s, 3H), 3.58 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 203.2, 198.6, 161.8, 160.1, 159.2, 146.7, 141.0, 140.1, 138.3, 137.3, 137.2, 135.7, 133.8, 133.7, 133.3, 131.3, 129.82, 129.78, 129.6, 128.84, 128.75, 128.67, 128.65, 128.6, 128.2, 127.7, 127.2, 126.8, 124.7, 122.8, 122.6, 118.7, 114.3, 113.9, 66.4, 58.53, 58.48, 56.8, 55.4; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C52H38Cl2O4H+ 797.2220, found 797.2206; IR (KBr thin film, cm−1): ν 2924, 2847. 1785, 1689, 1644, 1561, 1521, 1416, 1360, 1249, 1093, 1016, 829. 2,3,3a,5,6,7-Hexaphenyl-3a,4,7,7a-tetrahydro-1H-4,7-methanoindene-1,8-dione

(2f):

Yellow solid (66.6 mg, 54% yield). Mp 101−103 °C. 1H NMR (400 MHz, CDCl3) δ 7.68−7.66 (m, 2H), 7.44−7.40 (m, 4H), 7.33−7.27 (m, 3H), 7.23−7.13 (m, 6H), 7.06−6.87 (m, 11H), 6.67−6.63 (m, 2H), 6.48−6.45 (m, 2H), 4.66 (s, 1H), 3.88 (s, 1H);

13

C NMR

(100 MHz, CDCl3) δ 205.2, 196.5, 168.4, 146.8, 141.9, 141.7, 137.2, 134.4, 133.5, 133.3, 132.9, 131.8, 130.5, 129.8, 129.71, 129.65, 129.1, 128.6, 128.39, 128.35, 128.2, 128.1, 127.9, 127.8, 127.7, 127.6, 127.2, 126.7, 69.8, 59.5, 58.6, 57.4; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C46H32O2H+ 617.2475, found 617.2473; IR (KBr thin film, cm−1): ν 2947, 2853, 1709, 1638, 1556, 1547, 1516, 1416, 1337, 1016, 803, 667.


Page 15 of 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(3a,7a)-3a,5-bis(4-ethylphenyl)-2,7-bis(4-methoxyphenyl)-3,6-di-p-tolyl-3a,7a-dihydro1H-inden-1-one (2g): Yellow solid (124.6 mg, 85% yield). Mp 118−120 °C. 1H NMR (400 MHz, CDCl3) δ 7.32−7.25 (m, 4H), 7.13 (d, J = 8.2 Hz, 2H), 7.06−7.04 (m, 2H), 6.97−6.87 (m, 8H), 6.83−6.79 (m, 2H), 6.73−6.67 (m, 4H), 6.59−6.55 (m, 2H), 6.25 (d, J = 0.8 Hz, 1H), 3.88 (d, J = 0.8 Hz, 1H), 3.78 (s, 3H), 3.68 (s, 3H), 2.61 (q, J = 7.6 Hz, 1H) , 2.51 (q, J = 7.6 Hz, 1H), 2.22 (s, 3H), 2.13 (s, 3H), 1.21 (t, J = 7.6 Hz, 1H) , 1.13 (t, J = 7.6 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 205.2, 169.7, 159.3, 157.8, 142.8, 142.4, 140.4, 140.3, 139.0, 138.8, 136.4, 135.2, 134.9, 134.8, 133.7, 131.7, 131.2, 131.1, 131.0, 129.9, 128.9, 128.8, 128.5, 128.4, 128.0, 127.4, 127.0, 124.9, 113.8, 113.0, 66.3, 55.3, 55.1, 54.8, 28.5, 21.4, 21.3, 15.47, 15.45; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C53H48O3H+ 733.3676, found 733.3677; IR (KBr thin film, cm−1): ν 3276， 3162， 2955， 1706， 1635， 1573， 1411 ，1331， 1027， 931， 806. Dimethyl (E)-2'-styryl-[1,1':3',1''-terphenyl]-4',5'-dicarboxylate (3a): Yellow solid (161.5 mg, 90% yield). Mp 115−117 °C. 1H NMR (400 MHz, CDCl3) δ 8.03 (s, 1H), 7.42−7.30 (m, 10H), 7.18−7.14 (m, 3H), 6.84−6.82 (m, 2H), 6.61 (d, J = 16.7 Hz, 1H), 5.98 (d, J = 16.7 Hz, 1H), 3.91 (s, 3H), 3.58 (s, 3H);

13

C NMR (100 MHz, CDCl3) δ

169.1, 165.9, 142.4, 140.9, 139.84, 139.78, 137.9, 137.4, 137.2, 135.6, 131.6, 130.3, 129.8, 128.6, 128.5, 128.1, 127.92, 127.87, 127.7, 126.4, 125.5, 125.2, 52.7, 52.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C30H24O4H+ 449.1747, found 449.1748; IR (KBr thin film, cm−1): ν 3290, 3171, 2952, 1874, 1797, 1768, 1737, 1709, 1638, 1561, 1425, 1337, 1257, 800. Dimethyl (E)-2'-(4-chlorostyryl)-[1,1':3',1''-terphenyl]-4',5'-dicarboxylate (3b): Yellow solid (183.5 mg, 95% yield). Mp 121−122 °C. 1H NMR (400 MHz, CDCl3) δ 8.04 (s, 1H), 7.42−7.36 (m, 8H), 7.31−7.28 (m, 2H), 7.12−7.10 (m, 2H), 6.74 (d, J = 8.4 Hz, 2H), 6.57 (d, J = 16.7 Hz, 1H), 5.91 (d, J = 16.7 Hz, 1H), 3.91 (s, 3H), 3.58 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 169.0, 165.9, 142.4, 140.7, 139.8, 139.5, 137.8, 136.0, 135.64, 135.59, 133.6, 131.5, 130.2, 129.8, 128.7, 128.5, 128.1, 127.9, 127.7, 127.5, 126.1, 125.4, 52.7, 52.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C30H23ClO4H+ 483.1358, found



Page 16 of 26

483.1362; IR (KBr thin film, cm−1): ν 3285, 3171, 2941, 1984, 1865, 1740, 1723, 1644, 1573, 1414, 1340, 1138, 800. Dimethyl (E)-4''-methyl-2'-styryl-[1,1':3',1''-terphenyl]-4',5'-dicarboxylate (3c): Yellow solid (183.2 mg, 99% yield). Mp 130−133 °C. 1H NMR (400 MHz, CDCl3) δ 8.04 (s, 1H), 7.42−7.37 (m, 5H), 7.21−7.15 (m, 7H), 6.86 (d, J = 6.0 Hz, 2H), 6.65 (d, J = 16.7 Hz, 1H), 6.02 (d, J = 16.7 Hz, 1H), 3.91 (s, 3H), 3.62 (s, 3H), 2.41 (s, 3H);

13

C NMR (100

MHz, CDCl3) δ 169.2, 165.9, 142.3, 141.0, 140.0, 139.9, 137.4, 137.3, 137.2, 135.7, 134.8, 131.4, 130.1, 129.8, 128.8, 128.52, 128.45, 127.8, 127.6, 126.4, 125.6, 125.1, 52.6, 52.2, 21.4; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C31H26O4H+ 463.1904, found 463.1903; IR (KBr thin film, cm−1): ν 3293, 3165, 2952, 1720, 1641, 1553, 1422, 1337, 1280, 1257, 1135, 1022, 806. Dimethyl

(E)-4-chloro-4''-methoxy-2'-styryl-[1,1':3',1''-terphenyl]-4',5'-dicarboxylate

(3d): Yellow solid (190.8 mg, 93% yield). Mp 70−72 °C. 1H NMR (400 MHz, CDCl3) δ 7.98 (s, 1H), 7.40−7.34 (m, 4H), 7.23−7.16 (m, 5H), 6.94−6.89 (m, 4H), 6.62 (d, J = 16.7 Hz, 1H), 6.03 (d, J = 16.7 Hz, 1H), 3.91 (s, 3H), 3.84 (s, 3H), 3.62 (s, 3H);

13

C NMR

(100 MHz, CDCl3) δ 169.1, 165.8, 159.2, 141.0, 140.3, 139.7, 139.4, 137.6, 136.9, 136.2, 133.7, 131.4, 131.3, 131.2, 129.8, 128.7, 128.6, 128.1, 126.4, 125.31, 125.27, 113.6, 55.3, 52.7, 52.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C31H25ClO5H+ 513.1463, found 513.1466; IR (KBr thin film, cm−1): ν 3290, 3160, 2950, 1723, 1644, 1558, 1547, 1504, 1411, 1337, 1240, 1138, 1073, 803. Dimethyl 6'-phenyl-[1,1':2',1''-terphenyl]-3',4'-dicarboxylate (3e): Yellow solid (167.3 mg, 99% yield). Mp 160−162 °C. 1H NMR (400 MHz, CDCl3) δ 8.12 (s, 1H), 7.14−7.04 (m, 10H), 6.92−6.91 (m, 3H), 6.77−6.75 (m, 2H), 3.91 (s, 3H), 3.55 (s, 3H);

13

C NMR

(100 MHz, CDCl3) δ 169.2, 165.9, 144.9, 142.9, 140.4, 138.2, 137.7, 135.3, 131.1, 130.9, 130.3, 129.7, 127.9, 127.33, 127.25, 127.1, 127.0, 126.5, 126.2, 52.7, 52.2; HRMS (ESIion trap), m/z: [M+H]+ calcd. for C28H22O4H+ 423.1591, found 423.1597; IR (KBr thin film, cm−1): ν 3287, 3171, 2958, 1726, 1706, 1641, 1553, 1416, 1337, 1255, 1150, 1064, 812.


Page 17 of 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Dimethyl 4''-methyl-6'-phenyl-[1,1':2',1''-terphenyl]-3',4'-dicarboxylate (3f): Yellow solid (160.6 mg, 92% yield). Mp 150−152 °C. 1H NMR (400 MHz, CDCl3) δ 8.11 (s, 1H), 7.17−7.15 (m, 3H), 7.09−7.06 (m, 2H), 6.96−6.93 (m, 7H), 6.79−6.76 (m, 2H), 3.92 (s, 3H), 3.60 (s, 3H), 2.23 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 169.3, 166.0, 145.0, 142.9, 140.54, 140.48, 138.3, 136.6, 135.4, 134.7, 131.00, 130.97, 130.1, 129.8, 128.1, 127.9, 127.3, 127.0, 126.5, 126.2, 52.7, 52.3, 21.3; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C29H24O4H+ 437.1747, found 437.1749; IR (KBr thin film, cm−1): ν3 276, 3174, 2952, 1837, 1717, 1644, 1556, 1544, 1425, 1337, 1294, 1235, 1141, 800. 3',4',5'-Triphenyl-1,1':2',1''-terphenyl (4a): Yellow solid (66.0 mg, 36% yield). Mp 163−166 °C. 1H NMR (400 MHz, CDCl3) δ 7.59 (s, 1H), 7.19−7.17 (m, 10H), 6.95−6.93 (m, 6H), 6.88−6.86 (m, 7H), 6.81−6.79 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 141.88, 141.85, 140.9, 140.5, 140.1, 139.4, 131.7, 131.6, 131.5, 130.1, 127.7, 127.1, 126.8, 126.4, 125.7, 125.5; HRMS (EI-ion trap), m/z: M+ calcd. for C36H26+ 458.2029, found 458.2039; IR (KBr thin film, cm−1): ν 3285, 2947, 2927, 1587, 1436, 1411, 1266, 1047, 1013, 922, 704, 644. 4-Ethyl-3',4',5'-triphenyl-1,1':2',1''-terphenyl (4b): Yellow solid (68.1 mg, 35% yield). Mp 99−101 °C. 1H NMR (400 MHz, CDCl3) δ 7.59 (s, 1H), 7.18−7.16 (m, 5H), 7.09 (d, J = 8.1 Hz, 2H), 7.01 (d, J = 8.1 Hz, 2H), 6.95−6.93 (m, 6H), 6.88−6.86 (m, 7H), 6.80−6.78 (m, 2H), 2.59 (q, J = 11.4 Hz, 2H), 1.20 (t, J = 11.4 Hz, 3H); 13C NMR (100 MHz, CDCl3) δ 142.3, 141.92, 141.86, 140.9, 140.8, 140.6, 140.3, 140.2, 139.4, 139.2, 139.1, 131.7, 131.6, 130.1, 130.0, 127.7, 127.2, 127.1, 126.7, 126.3, 125.69, 125.65, 125.4, 28.5, 15.5; HRMS (EI-ion trap), m/z: M+ calcd. for C38H30+ 486.2342, found 486.2344; IR (KBr thin film, cm−1): ν 3285, 3182, 2986, 2935, 1700, 1641, 1573, 1416, 1044, 1016, 925, 815. 650. 4-Methyl-3',4',6'-triphenyl-1,1':2',1''-terphenyl (4c): Yellow solid (60.5 mg, 32% yield). Mp 186−189 °C. 1H NMR (400 MHz, CDCl3) δ 7.56 (s, 1H), 7.17−7.16 (m, 10H), 6.94−6.92 (m, 3H), 6.89−6.85 (m, 5H), 6.81−6.78 (m, 2H), 6.73 (s, 4H), 2.15 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 142.1, 141.94, 141.91, 141.0, 140.7, 140.6, 140.2, 139.42, 139.39, 136.9, 135.1, 131.7, 131.64, 131.58, 131.5, 130.1, 127.8, 127.71, 127.70, 127.0,



Page 18 of 26

126.7, 126.34, 126.28, 125.7, 125.4, 21.2; HRMS (EI-ion trap), m/z: M+ calcd. for C37H28+ 472.2186, found 472.2191; IR (KBr thin film, cm−1): ν 3276, 3165, 2921, 1689, 1644, 1567, 1414, 1337, 1044, 1016, 928, 797. 4-Methyl-3',5',6'-triphenyl-1,1':2',1''-terphenyl (4d): Yellow solid (60.5 mg, 32% yield). Mp 198−200 °C. 1H NMR (400 MHz, CDCl3) δ 7.56 (s, 1H), 7.17−7.13 (m, 10H), 6.95−6.93 (m, 6H), 6.87−6.84 (m, 4H), 6.69−6.64 (m, 4H), 2.11 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 142.0, 141.8, 140.9, 140.3, 139.5, 137.3, 134.8, 131.7, 131.5, 131.4, 130.1, 127.7, 127.5, 127.0, 126.3, 125.6, 21.2; HRMS (EI-ion trap), m/z: M+ calcd. for C37H28+ 472.2186, found 472.2192; IR (KBr thin film, cm−1): ν 3276, 3174, 2995, 1706, 1638, 1573, 1419, 1345, 1050, 1010, 922, 803. 4-Ethyl-3'-(4-methoxyphenyl)-4''-methyl-4',5'-diphenyl-1,1':2',1''-terphenyl (4e): Yellow solid (63.7 mg, 30% yield). Mp 197−199 °C. 1H NMR (400 MHz, CDCl3) δ 7.54 (s, 1H), 7.14 (s, 5H), 7.07 (d, J = 8.1 Hz, 2H), 7.00 (d, J = 8.1 Hz, 2H), 6.95−6.93 (m, 3H), 6.85−6.83 (m, 2H), 6.77−6.72 (m, 4H), 6.68−6.66 (m, 2H), 6.44−6.42 (m, 2H), 3.63 (s, 3H), 2.59 (q, J = 7.6 Hz, 2H), 2.18 (s, 3H), 1.21 (t, J = 7.6 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 157.2, 142.11, 142.07, 141.5, 140.9, 140.7, 140.4, 139.6, 139.5, 139.3, 137.2, 134.9, 133.1, 132.6, 131.7, 131.6, 131.5, 130.1, 130.0, 127.9, 127.7, 127.2, 127.1, 126.2, 125.6, 112.3, 55.1, 28.5, 21.3, 15.5; HRMS (EI-ion trap), m/z: M+ calcd. for C40H34O+ 530.2604, found 530.2615; IR (KBr thin film, cm−1): ν 3282, 2918, 1686, 1641, 1575, 1428, 1340, 1013, 925, 812, 647. 4,4''-Dichloro-5'-(4-ethylphenyl)-3'-(4-methoxyphenyl)-4'-(p-tolyl)-1,1':2',1''-terphenyl (4f): Yellow solid (40.8 mg, 17% yield). Mp 210−212 °C. 1H NMR (400 MHz, CDCl3) δ 7.47 (s, 1H), 7.15 (d, J = 8.4 Hz, 2H), 7.05−6.98 (m, 6H), 6.94 (d, J = 8.4 Hz, 2H), 6.76−6.73 (m, 4H), 6.69 (d, J = 8.1 Hz, 2H), 6.63 (d, J = 8.6 Hz, 2H), 6.44 (d, J = 8.6 Hz, 2H), 3.65 (s, 3H), 2.58 (q, J = 7.6 Hz, 2H), 2.17 (s, 3H), 1.20 (t, J = 7.6 Hz, 2H);

13

C

NMR (100 MHz, CDCl3) δ 157.4, 142.4, 141.7, 141.4, 140.22, 140.16, 139.3, 139.0, 138.7, 138.1, 136.9, 135.1, 132.9, 132.6, 132.5, 131.8, 131.5, 131.4, 131.3, 129.9, 128.1, 127.9, 127.6, 127.3, 112.5, 55.1, 28.5, 21.3, 15.5; HRMS (EI-ion trap), m/z: M+ calcd. for


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C40H32Cl2O+ 598.1825, found 598.1833; IR (KBr thin film, cm−1): ν 3253, 2950, 2921, 2862, 1743, 1609, 1547, 1516, 1453, 1243, 1096, 832, 712. 3,3''-difluoro-3',5'-diphenyl-4'-(p-tolyl)-1,1':2',1''-terphenyl (4g): Yellow solid (50.2 mg, 49% yield). Mp 103–105 °C. 1H NMR (600 MHz, CDCl3) δ 7.51 (s, 1H), 7.18–7.10 (m, 6H), 6.94–6.83 (m, 7H), 6.81–6.75 (m, 2H), 6.71 (q, J = 8.1 Hz, 4H), 6.67–6.60 (m, 2H), 6.58–6.52 (m, 2H), 2.13 (s, 3H). 13C NMR (151 MHz, CDCl3) δ 163.0 (d, J = 55.9 Hz), 161.3 (d, J = 3.0 Hz), 143.7 (d, J = 7.6 Hz), 142.1 (d, J = 7.6 Hz), 142.0, 141.5 (d, J = 22.7 Hz), 140.0, 139.9, 139.3, 138.0, 136.5, 135.3, 131.3, 130.9, 130.0, 129.8, 129.2 (d, J = 9.1 Hz), 128.6 (d, J = 9.1 Hz), 128.0, 127.8, 127.8, 127.4, 127.3, 126.9 (d, J = 13.6 Hz), 126.4, 125.7, 118.3 (d, J = 21.1 Hz), 116.8 (d, J = 22.7 Hz), 113.5 (d, J = 2.1 Hz), 112.9 (d, J = 19.6 Hz), 21.2. HRMS (EI-ion trap), m/z: M+ calcd. for C37H26F2+ 508.1997, found 508.2028; IR (KBr thin film, cm-1): ν 2921, 1646, 1612, 1581, 1493, 1436, 1266, 1195, 877, 766, 704. 4,4''-dibromo-3', 5'-diphenyl-4'-(p-tolyl)-1, 1':2', 1''-terphenyl (4h): Yellow solid (50.1 mg, 40% yield). Mp 210–212 °C. 1H NMR (600 MHz, CDCl3) δ 7.49 (s, 1H), 7.33–7.30 (m, 2H), 7.18–7.15 (m, 3H), 7.14–7.12 (m, 2H), 7.10–7.06 (m, 2H), 7.01–6.98 (m, 2H), 6.91–6.88 (m, 3H), 6.75–6.71 (m, 4H), 6.69 (m, 4H), 2.14 (s, 3H).13C NMR (151 MHz, CDCl3) δ 142.1, 141.7, 141.5, 140.5, 140.1, 139.9, 139.3, 138.9, 137.9, 136.5, 135.3, 133.2, 131.7, 131.5, 131.4, 131.1, 130.5, 130.0, 127.9, 127.8, 127.0, 126.5, 125.72, 120.9, 120.2, 21.2. HRMS (EI-ion trap), m/z: M+ calcd. for C37H26Br2+ 628.0396, found 628.0429; IR (KBr thin film, cm-1): ν 2924, 2359, 1644, 1490, 1385, 1263, 1073, 1019, 817, 761.

5'-(4-chlorophenyl)-4-ethyl-3'-(4-methoxyphenyl)-4''-methyl-4'-phenyl-1,1':2',1''-terphenyl and

(4i)

4'-(4-chlorophenyl)-4-ethyl-3'-(4-methoxyphenyl)-4''-methyl-5'-phenyl-1,1':2',1''-terphenyl

(4j) Yellow solid (36.1 mg, 32% yield). Mp 170–172 °C 1H NMR (600 MHz, CDCl3) δ 7.52 (s, 2H), 7.48 (s, 1H), 7.19–7.14 (m, 5H), 7.13–7.09 (m, 6H), 7.07–7.03 (m, 7H), 6.99 (dd, J = 8.1, 3.9 Hz, 5H), 6.97–6.93 (m, 3H), 6.92–6.88 (m, 2H), 6.81 (dd, J = 6.5, 2.6 Hz, 9H), 6.70 (d, J = 7.9 Hz, 5H), 6.67–6.61 (m, 5H), 6.46–6.38 (m, 5H), 3.64 (s, 5H), 3.62 (s, 3H), 2.58 (dt, J = 9.9, 6.4 Hz, 5H), 2.16 (s, 8H), 1.19 (td, J = 7.6, 2.2 Hz, 8H). 13C NMR (151 MHz, CDCl3) δ 157.2,



157.2, 142.2, 141.7, 141.4, 141.2, 141.0, 140.6, 140.5, 140.1, 139.9, 139.7, 139.3, 139.1, 139.0, 138.0, 137.0, 134.9, 132.9, 132.8, 132.7, 132.5, 132.3, 131.6, 131.6, 131.5, 131.4, 131.3, 130.0, 129.9, 127.9, 127.3, 127.2, 127.2, 126.4, 125.7, 112.4, 112.2, 55.1, 55.0, 28.5, 21.2, 15.4. HRMS (EI-ion trap), m/z: M+ calcd. for C40H33O + 564.2214, found 564.2241; IR (KBr thin film, cm-1): ν 2961, 1638, 1519, 1436, 1382, 1246, 1181, 1090, 1013, 826, 746.

1-Hydroxy-2,3a,5,7-tetraphenyl-3,6-di((E)-styryl)-3a,4,7,7a-tetrahydro-1H-4,7methanoinden-8-one (5a). To a 5 mL round-bottom flask was added 2a (133.8 mg, 0.2 mmol). The flask was vacuumized and refilled with dry argon. Anhydrous MeOH (0.5 mL) and THF (1.0 mL) was added and the solution was cooled to 0 °C. Then NaBH4 (15.1 mg, 0.4 mmol) was added to the flask under argon protection. After addition was complete, the reaction was allowed to warm to room temperature and was stirred for 1 h under argon atmosphere. The reaction was diluted with water (3 mL) and extracted with Et2O (3 mL) for three times, dried over anhydrous Na2SO4, and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel with petroleum ether/ethyl acetate (5:1 v/v) as eluent afforded 132.8 mg (99% yield) of compound 5a.Yellow solid. Mp 145−147 °C. 1H NMR (400 MHz, CDCl3) δ 7.73−7.68 (m, 4H), 7.40−7.34 (m, 4H), 7.33−7.18 (m, 11H), 7.15−7.03 (m, 8H), 6.95−6.91 (m, 1H), 6.84 (d, J = 16.6 Hz, 1H), 6.69 (d, J = 7.1 Hz, 2H), 6.61 (d, J = 16.5 Hz, 1H), 6.30 (d, J = 16.5 Hz, 1H), 5.87 (d, J = 16.6 Hz, 1H), 4.59 (s, 2H), 4.10 (s, 1H), 1.80 (d, J = 3.4 Hz, 1H);

13

C NMR (100 MHz, CDCl3) δ 206.3, 166.3, 143.0, 142.4, 141.9, 139.1, 139.0,

138.0, 137.1, 136.4, 136.2, 134.7, 131.5, 130.2, 130.0, 128.9, 128.8, 128.53, 128.49, 128.43, 128.38, 128.3, 128.2, 128.0, 127.5, 127.4, 127.3, 127.2, 127.1, 126.9, 126.6, 123.3, 120.5, 92.2, 68.4, 63.6, 61.3, 52.6; HRMS (ESI-ion trap), m/z: [M+H]+ calcd. for C50H38O2H+ 671.2945, found 671.2949; IR (KBr thin film, cm−1): ν 3273, 2995, 1683, 1641, 1567, 1419, 1101, 1036, 1016, 915, 810, 640. 2,3a,5,7-Tetraphenyl-3,6-di((E)-styryl)-3a,4,7,7a-tetrahydro-1H-4,7-methanoindene-1,8diol (6a): To a 5 mL round-bottom flask was added 2a (133.8 mg, 0.2 mmol). The flask was vacuumized and refilled with dry argon. Anhydrous THF (2.0 mL) was added and the solution was cooled to 0 °C. Then LiAlH4 (30.4 mg, 0.8 mmol) was added to the flask under argon protection. After addition was complete, the reaction was allowed to warm to


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room temperature and was stirred for 1 h under argon atmosphere. The reaction was diluted with water (3 mL) and extracted with Et2O (3 mL) for three times, dried over anhydrous Na2SO4, and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel with petroleum ether/ethyl acetate (4:1 v/v) as eluent afforded 107.7 mg (80% yield) of compound 6a. Yellow solid. Mp 150−152 °C. 1

H NMR (400 MHz, CDCl3) δ 7.60−7.58 (m, 4H), 7.49−7.31 (m, 14H), 7.20−7.06 (m,

9H), 6.99−6.97 (m, 2H), 6.80 (d, J = 7.4 Hz, 2H), 6.36 (d, J = 16.6 Hz, 1H), 6.24 (d, J = 16.6 Hz, 1H), 6.08 (t, J = 10.1 Hz, 1H), 5.81 (d, J = 16.7 Hz, 1H), 4.76 (s, 1H), 4.54 (s, 1H), 4.05 (d, J = 9.2 Hz, 1H), 1.89−1.84 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 145.9, 145.7, 143.5, 142.7, 138.8, 138.5, 137.5, 137.3, 136.1, 135.2, 133.6, 132.7, 130.3, 129.6, 129.1, 128.7, 128.52, 128.49, 128.4, 128.3, 128.14, 128.09, 127.8, 127.7, 127.6, 127.2, 126.9, 126.5, 126.4, 126.3, 122.6, 121.0, 90.6, 78.0, 70.3, 66.4, 57.4, 54.2; HRMS (ESIion trap), m/z: [M+H]+calcd. for C50H40O2Na+ 695.2921, found 695.2914; IR (KBr thin film, cm−1): ν 2920, 2846, 1650, 1545, 1492, 1410, 1347, 1223, 1090, 1025, 968, 697. (E)-(2'-Styryl-[1,1':3',1''-terphenyl]-4',5'-diyl)dimethanol (7a): To a 5 mL round-bottom flask was added 3a (89.7 mg, 0.2 mmol). The flask was vacuumized and refilled with dry argon. Anhydrous THF (1.0 mL) was added and the solution was cooled to 0 °C. Then LiAlH4 (15.2 mg, 0.4 mmol) was added to the flask under argon protection. After addition was complete, the reaction was allowed to warm to room temperature and was stirred for 1 h under argon atmosphere. The reaction was diluted with water (3 mL) and extracted with Et2O (3 mL) for three times, dried over anhydrous Na2SO4, and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel with petroleum ether/ethyl acetate (1:1 v/v) as eluent afforded 42.4 mg (54% yield) of compound 7a. Yellow solid. Mp 50−52 °C. 1H NMR (400 MHz, CDCl3) δ 7.45−7.29 (m, 10H), 7.17−7.09 (m, 3H), 6.82−6.80 (m, 2H), 6.57 (d, J = 16.7 Hz, 1H), 5.86 (d, J = 16.7 Hz, 1H), 4.83 (s, 2H), 4.54 (s, 2H), 3.48 (br, 1H), 3.21 (br, 1H); 13C NMR (100 MHz, CDCl3) δ 142.7, 141.8, 141.4, 139.8, 138.8, 137.8, 136.9, 135.5, 135.4, 131.7, 130.3, 130.0, 128.44, 128.35, 128.3, 127.34, 127.30, 127.10, 127.07, 126.2, 64.8, 60.2; HRMS (ESI-ion trap), m/z: [M+H]+calcd. for C28H24O2Na+ 415.1669,



found 415.1674; IR (KBr thin film, cm−1): ν 3437, 2996, 1692, 1633, 1571, 1412, 1347, 1110, 1039, 1011, 929, 804. (E)-4,6-diphenyl-5-styrylbenzo[d][1,3]dioxole (8a): To a 5 mL round-bottom flask was added 7a (39.3 mg, 0.1 mmol). The flask was vacuumized and refilled with dry argon. Anhydrous CH2Cl2 (1.0 mL) was added and the solution was cooled to -78 °C. Then DMSO (35 weiL, 0.5 mmol) in CH2Cl2 (1.0 mL) was added. After addition was complete, the reaction was stirred for 1 h at -78 oC under argon atmosphere and then Et3N (0.3 mL) was added. Then it was warmed to room temperature. After 1 h, the reaction was poured into water and extracted with Et2O (3 mL) for three times, dried over anhydrous Na2SO4, and concentrated under reduced pressure. Purification of the residue by column chromatography on silica gel with petroleum ether/ethyl acetate (10:1 v/v) as eluent afforded 20.0 mg (53% yield) of compound 8a. Yellow solid. Mp 129−131 °C. 1H NMR (400 MHz, CDCl3) δ 7.49−7.35 (m, 11H), 7.16−7.11 (m, 3H), 6.80 (d, J = 6.8 Hz, 2H), 6.52 (d, J = 16.7 Hz, 1H), 5.87 (d, J = 16.7 Hz, 1H), 4.89 (s, 2H), 4.58 (s, 2H); 13C NMR (100 MHz, CDCl3) δ 143.3, 142.4, 141.3, 138.9, 137.6, 136.4, 136.0, 135.4, 133.9, 132.6, 130.2, 129.9, 128.50, 128.47, 128.4, 127.8, 127.5, 127.4, 126.6, 126.2, 44.0, 40.9; HRMS (ESI-ion trap), m/z: [M+H]+calcd. for C28H22OH+ 375.1743, found 375.1741; IR (KBr thin film, cm−1): ν 3517, 3242, 3057, 1663, 1609, 1544, 1487, 1445, 1357, 1266, 749, 698. (E)-2-(4-Chlorostyryl)-4-oxo-1,3-diphenylcyclopent-2-en-1-yl 4-bromobenzoatel (2b’): Yellow solid (189.2 mg, 83% yield). Mp 51−53 °C. 1H NMR (400 MHz, CDCl3) δ 7.97−7.94 (m, 2H), 7.72−7.70 (m, 2H), 7.61−7.58 (m, 4H), 7.54−7.40 (m, 6H), 7.17−7.15 (m, 2H), 7.10−7.06 (m, 3H), 6.58 (d, J = 16.6 Hz, 1H), 3.87 (d, J = 23.4 Hz, 1H), 3.47 (d, J = 23.4 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 205.7, 164.5, 142.1, 135.6, 135.5, 135.4, 133.7, 133.6, 132.3, 132.1, 131.4, 129.3, 129.1, 129.0, 128.9, 128.8, 128.7, 128.1, 127.7, 125.9, 120.4, 44.1; HRMS (ESI-ion trap), m/z: [M+H]+calcd. for C32H22BrClO3H+ 569.0514, found 569.0512; IR (KBr thin film, cm−1): ν 3282, 1639, 1571, 1410, 1274, 1096, 1048, 1022, 923, 810, 759.

ASSOCIATED CONTENT


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Supporting Information The Supporting Information is available free of charge via the Internet on the ACS Publications website at DOI: X-ray structure of 2b (CIF) NMR spectra for new compounds (PDF) COSY and NOSEY spectra of 5a and 6a (PDF) AUTHOR INFORMATION Corresponding Authors *Email: [email protected] *Email: [email protected] Notes The authors declare no competing financial interest. ACKNOWLEDGEMENTS This work was supported by National Science Foundation of China (21502192,), the strategic priority research program of the Chinese Academy of Sciences (XDB20000000), the Chinese Recruitment Program of Global Experts, the hundred talents program of Fujian Province. We thank Professor Daqiang Yuan for the X-ray data analysis. REFERENCES 1. Ogliaruso, M. A.; Romanelli, M. G.; Becker, E. I. Chemistry of Cyclopentadienones. Chem. Rev. 1965, 65, 261−367. 2. (a) Fujita, M.; Sakanishi, Y.; Nishii, M.; Okuyama, T. Cycloheptyne Intermediate in the Reaction of Chiral Cyclohexylidenemethyliodonium Salt with Sulfonates. J. Org. Chem. 2002, 67, 8138−8146. (b) Rainier, J. D.; Imbriglio, J. E. Synthesis and Chemoselective Reactivity of 3-Aminocyclopentadienones. Org. Lett. 1999, 1, 2037−2039. 3. (a) Gleiter, R.; Werz, D. B. Reactions of Metal-Complexed Carbocyclic 4π Systems. Organometallics 2005, 24, 4316−4329. (b) Shvo, Y.; Czarkie, D.; Rahamim, Y. A New Group of Ruthenium Complexes: Structure and Catalysis. J. Am. Chem. Soc. 1986, 108,



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Cyclopentadienone Formation from Î²,Î³ ... - ACS Publications

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