Organometallics 1983, 2, 191-193
191
83802-18-0;2 (M = Ru, R = R' = n-Pr), 83802-19-1; 2 (M = Ru, ization over the C(7)-C(8)-C(9)-N fragment as might be R = R' = 2-EtC5H9),83802-20-4;Fe2(CO)6(~-s2-C=CPh)(PPh2), expected for a planar skeleton. In stereochemical terms, 52970-25-9;RU2(C0)6(~-)72-CECPh)(PPh2), 82647-81-2; Et2NH, addition of the secondary amine across the alkynyl group 109-89-7; Pr2NH, 142-84-7; PhNH2, 1484-80-6; 2-ethylpiperidine, is regiospecific, there being no spectroscopic or synthetic 62-53-3. evidence for a 2-diethylamino 3-phenyl isomer. The iron derivative 2 (M = Fe, R = Ph, R' = H) is also formed Supplementary Material Available: Table I, atomic posregiospecifically via /3 attack (Figure 2), but in the resulting itions Table 11, anisotropic thermal parameters, Table 111,bond lengths, Table IV, bond angles, and a listing of observed and enamine the addenda are mutually trans. In this case the calculated structure factor amplitudes for Ru2(CO)&O= stereochemistry of the product appears to be controlled CCHC(Ph)NEtJ(PPhJ (25 pages). Ordering information is given by hydrogen bonding between the carbonyl oxygen O(7) on any current masthead page. and the amine hydrogen atom.ls The ruthenium-aniline adduct may have similar stereochemistry. Several features of these reactions and products are notable in the context of CO chemistry., Complexes of type Allylation of Aldehydes and Ketones in the Presence 2 are closely similar to intermediates postulated by Wilof Water by Allyllc Bromides, Metallic Tin, and kinson and co-workers in CO reductions to oxygenated products catalyzed by binuclear ruthenium catalyst^.^ Aluminum Moreover the synthesis of 2 from a multisite bound ligand Junzo Nokami, * Junzo Otera, Takuzo Sudo, and with demonstrated carbocationic character,lg carbon monoxide, and a base suggests the possibility of accomRokuro Okawara plishing selective additions to other carbocations in biOkayama University of Science nuclear or cluster compounds. It is particularly noteworthy Ridai, Okayama 700, Japan that the direction of addition, with amine functionalization Received July 22, 1982 of the acetylene differs from that observed in Reppe reactions5 or in stoichiometric carbonylations of acetylenes Summary: Allylation of aldehydes and ketones to give the by metal carbonyls in the presence of added bases where homoallyl alcohol can be carried out successfully by allyl the nucleophile is attached to the carbonyl group. bromide and metallic tin in the presence of water, and Possible mechanisms for the carbonylation-amination also the allylation by various allylic bromides is successful sequence leading to 2 include direct CO insertion into the presence (PP ~ ~ ) of water by using metallic tin and alumetal-acetylide bond of Mz ~ C ~ ) , ( ~ L - ? ~ - C ~ C P ~in) the minum. followed by amine addition across the triple bond or intramolecular coupling of the acetylide and a carboxamide Allylaton at the carbonyl carbon of aldehydes or ketones group generated via amine attack on coordinated CO. by di-n-butylallyltin chloride,l" diallyltin dibromide ( 1)2 There is now ample precedent for p-q2- or q-bonded carat -70 OC, or its analogues, i.e., tin and CH2=CHCH2X boxamide species in other However, the pre(X = Br, 1),lbor SnC12and CH2=CHCH21 at room temcursors M2(CO)6(~-?2-CrCPh)(PPh2) do not insert CO perature,lc has been reported to give the corresponding even under pressure, and in the absence of added CO homoallyl alcohol. However, we have often encountered amine addition to the acetylenic triple bond is extremely difficulties in that the allylation in a nonaqueous solvent facile, there being no spectroscopic evidence for carboxat room temperature does not proceed easily. For example, amide species. A more likely mechanism is direct CO in the reaciton of 1 with benzaldehyde in dry ether, insertion into the dipolar p-alkylidene complex 39 or the benzene, or ethyl acetate, the yield of the homoallyl alcohol p-vinylidene species 49 formed via amine attack on the usually was less than 50%, even after a reaction time of triple bond. Such insertions, which are of obvious interest 10 h, and the starting materials were recovered after in the context of C-C bond forming processes in hydroworkup with water. As this reaction seemed to be accelcarbon synthesis,20are presently under investigation. erated by the addition of water, we were successful in completing the allylation by carrying out the reaction in Acknowledgment. We are grateful to NSERC and the presence of water. An example follows below. Water Imperial Oil Ltd. for financial support of this work in the (2 mL) was added to a solution of benzaldehyde (212 mg, form of grants (A.J.C.) and a scholarship (S.A.M.) 2 mmol) in ether (2 mL). To this heterogeneous mixture Registry No. 2 (M = Fe, R = Ph, R' = H), 83802-16-8; 2 (M was added 1 (360 mg, 1mmol), and stirring was continued = Ru, R = Ph, R' = H), 83802-17-9; 2 (M = Ru, R = R' = Et), for 1.5 h at room temperature. The organic layer was separated, washed with brine, and dried over anhydrous (14) The C(8)-C(9) bond length of 1.394(6) A is somewhat longer than sodium sulfate. Removal of ether in vacuo gave the corthe standard C(sp2!-C(sp2) double bond length (1.337 (6) A) in 01efins'~ responding homoallyl alcohol, 1-phenylbut-3-en-1-01 in and the C(9)-N distance (1.334 (7) A) can be compared with corre75% yield after column chromatography on silica gel. sponding values for >C=N< bond lengths in N,N-dimethylisopropylideniminium perchlorate (1.30 (2) A)16or 2,6-dihydroxypyridinium From a synthetic point of view, it is desirable to replace cation (1.346 (3) and 1.335 (3) where there is unquestionably C-N 1 by allyl bromide and metallic tin as shown in eq l.3 Also, multiple bonding. (15) Kennard, O., Watson, D. G., Allen, F. H., Isaacs, N. W., Motherwell. W. D. s..Petterson. R. C.: Town. W. G. Eds. "Molecular Structures and Dimensions"; N. V. A. Oosthoek:' Utrecht, Vol. Al, p 52. (16) Trefonas, L. M.; Flurry, R. L., Jr.; Majeste, R.; Mayers, E. A.; Copeland, R. F. J. Am. Chem. SOC.1966,88, 2145. (17) Mason, S. A.; White, J. C. B.; Woodlock, A. Tetrahedron Lett. 1969,5219. (18) In the iron dimer the 0(7)-C(7)-C(S)-C(9)-N unit is planar. With an N-H distance of 0.95 A, the hydrogen atom would be located -1.80 A from 0(7), a value compatible with a hydrogen bond interaction. (19) Carty, A. J. Pure Appl. Chem. 1982, 54, 113. (20) Dyke, A. F.; Guerchais, J. E.; Knox, S. A. R.; Roue, J.; Short, R. L.; Taylor, G. E.; Woodward, P. J. Chem. SOC.,Chem. Commun. 1981, 537.
0276-7333/83/2302-0191$01.50/0
+
H2O
R1COR2+ CH2=CHCH,Br l/zSn R1R2C(OH)CHzCH=CH2(1) (1) (a) Peruzzo, V.; Tagliavini, G. J . Organomet. C h e n . 1978, 162, 37-44. Gambaro, A.; Peruzzo, V., Plazzogna, G.; Tagliavini, G. Ibid. 1980, 197,45-50. (b) Mukaiyama, T.; Harada, T. Chem. Lett. 1981,1527-1528. (c) Mukaiyama, T.; Harada, T.; Shoda, S. Ibid. 1980, 1507-1510. (2) The reaction of allyl bromide with metallic tin is known to give diallyltin dibromide: (a) Vijayaraghavan, K. V. J . Indian Chem. SOC. 1945,22, 135-140; Chem. Abstr. 1946,40, 2787. (b) Sisido, K.; Takeda, Y. J . Org. Chem. 1961, 26, 2301-2304.
0 1983 American Chemical Society
192 Organometallics, Vol. 2, No. 1, 1983
Communications
Table I. Allylation of Aldehydes and Ketones b y Allyl Bromide and Metallic Tin in the Presence of Watera at Room Temperature allyl bromide, mmol 1.96 1.96 1.96 1.90 1.96 2.08 1.96 1.96 1.96
Sn mmol 0.77 0.85 0.82 0.82 0.82 0.91 0.83 0.82 0.81 9
aldehyde or ketone (mmol) PhCHO (1.35) CH,(CH,),CHO (1.46) CH,CH=CHCHO (1.30) citral (1.37) cyclohexanone (1.32) 2-methylcyclohexanone (1.52) CH,(CH,),COCH, (1.28) CH,COCH,CH,COOH (1.34) PhCOCH, (1.43)
homoallyl alcohol yield,b % 7 3 (75) 70 (87) 57 ( 7 9 ) 6 8 (79) 76 (70) 45 (59) 58 (61) 4 7 c (60) 50 ( 6 2 )
reaction time, n 2 2 2 2 3
12 12 12 12
The reaction system consisted of ether (1 mL), water (1mL), and hydrobromic acid (5%, 0.1 mL). After purification, based on aldehyde or ketone. The yield in parentheses shows that of by using diallyltin dibromide 1 (0.5 molar equiv to aldehyde or ketone). 3-Allyl-4-valerolactone. Table 11. Synthesis of p-Methylhomoallyl Alcohol metallic aldehyden (mmol) PhCHO (1.42)
CH,CHO (20.0)
I-bromobut2-ene, mmol 1.94
19.4
Sn, mmol 0.81
A4 mmol 0.85
8.3
18.0
solvent (mL) Et,O/H,O (2/1) THF/H,O (210.2) Et,O/H?O
CH,(CH,),CHO (1.37)
(CH,),CHCHO (20.1)
reaction time, h
yield, 470 (erythro/ threo)
9 2 15 12
19.4
8.4
19.0
THF/H,o (2/0.2) EtOH/H,O (2/0.2) Et ,O/H, 0
2 5 15 12
CH,CH=CHCHO ( 1 . 7 4 ) TH F/I-I ,0
2 9
citral (1.40)
2 a Commerciallv available material was used without Durification. authentic sample prepared.’
The ratio was determined by GPC based on the
in this system, satisfactory results were obtained (Table I). A typical procedure is as follows. The heterogeneous mixture of hexanal (1.46mmol), d y l bromide (1.96 mmol), commercially available tin powder (200 mesh, 0.85 mmol), ether (1mL), and water (1mL)4was vigorously stirred at room temperature, and dilute hydrobromic acid (5%, 0.1 mL) was added to this mixture. After 2 h, the organic layer was separated, washed with brine, dried, and distilled (Kugelrohr) to give the homoallyl alcohol non-1-en-4-01in 70% yield. In addition, reactions involving metalLic tin and a variety of allylic bromides were carried out. In these reactions, we have found that the addition of metallic aluminum (commercially available powder or dramatically improves the yield6 (Table 11). For example, the synthesis of P-methylhomodyl alcohols7will be shown. The mixture
of 1-bromobut-2-ene (2, 2.62 g, 19.4 mmol) and acetaldehyde (1.0 g, ca. 90%, 20.0 mmol) was dissolved in ether (5 mL), and water (3 mL), tin powder (1g, 200 mesh, 8.4 mmol), aluminum powder (0.5 g, 200 mesh, 18.5 mmol), and a catalytic amount of hydrobromic acid were added. The mixture was vigorously stirred for 15 h at room temperature. The organic layer was separated, washed with brine, dried, and distilled (Kugelrohr) to give 3-methylpent-1-en-3-01 quantitatively. From Table 11, it is clearly shown that the further improvement of the yield can be attained in some cases by changing ether to THF. Prenyl bromide, methyl ll-bromoundec-9-enoate, and 1-bromohept-2-enecan react with aldehydes, under conditions similar to those shown in Table 11, to give the corresponding homoallylic alcohols in fairly satisfactory yield. Also, some larger scale experiments8 showed satis-
(3) I t is known that the reactin of benzyl chloride with metallic tin proceeds in boiling water to give tribenzyltin chloride: Sisido, K.; Takeda, Y.; Kinugawa, Z. J. Am. Chem. SOC.1961,83, 538-541. (4) We could not observe the product in dry THF or ether by TLC monitoring even when the activated metallic tinZbwas used. However, the formation of the product could be confirmed after the addition of water into the mixture to workup. ( 5 ) Aluminu chloride, alumnum oxide, or metallic zinc were ineffective. (6) Among the aldehydes shown in Table 11, only benzaldehyde can react with 2 without aluminum to give the product in ca. 60% yield.
(7) Yamamoto, Y.; Yatagai, H.; Naruta, Y.; Maruyama, K. J . A m . Chem. SOC.1980, 102, 7107-7109. (8) For example, to the heterogeneous mixture of allyl bromide (0.1 mol), tin powder (0.05 mol), water (20 mL), and a catalytic amount of hydrobromic acid, cyclohexanone (0.1 mol) was added dropwise during 0.5-1 h with vigorous stirring. After the tin was disappeared, the stirring was continued for additional 2-3 h. The reaction mixture was neutralized with sodium carbonate. The product obtained by steam distillation was extracted with ether and purified by distillation under reduced pressure (63 OC (0.6 torr), 77%).
Organometallics 1983,2,193-194
193
factory results. Thus a wide applicability of this reaction has been confirmed. Registry NO.2,4784-77-4; PhCHO, 100-52-7;CH3(CH2)4CHO, 66-25-1; CH&H=CHCHO, 4170-30-3; CH3(CH2)&OCH3, 11113-7; CH3COCH&H2CO2H, 123-76-2; PhCOCH3, 98-86-2; CH2=CHCH2Br, 106-95-6; CH3CH0, 75-07-0; Sn, 7440-31-5; Al, 7429-90-5; H20, 7732-18-5; PhCHO homoallyl alcohol, 936-58-3; CH3(CH2),CH0homoallyl alcohol, 35192-73-5; CH3CH=CHCH0 homoallyl alcohol, 5638-26-6 CH3(CH2)&OCH3homoallyl alcohol, 38564-33-9;PhCOCH3 homoallyl alcohol, 4743-74-2; (CH3)2CHCHO, 78-84-2; PhCHO (R*,S*)-P-methylhomoallyl alcohol, 52922-19-7; PhCHO (R*,R*)-P-methylhomoallyl alcohol, 52922alcohol, 1538-23-4; 10-8; CH3CH0 (R*,R*)-P-methylhomoallyl CH3CH0 (R*,S*)-P-methylhomoallyl alcohol, 1538-22-3;CH3(Calcohol, 52922-22-2; CH3H2)4CH0(R*,R*)-P-methylhomoallyl (CHJ4CH0 (R*,S*)-P-methylhomoallyl alcohol, 52922-27-7; (CH3)2CHCH0(R*,R*)-P-methylhomoallyl alcohol, 1502-91-6; alcohol, 1502-90-5; (CH3),CHCH0 (R*,S*)-p-methylhomoallyl CH,CH=CHCHO (R*,R*)+methylhomdyl alcohol, 78377-341; CH3CH=CHCH0 (R*,S*)-P-methylhomoallyl alcohol, 78377-32-9; citral homoallyl alcohol, 28897-20-3; cyclohexanone homoallyl alcohol, 1123-34-8; 2-methylcyclohexanone homoallyl alcohol, 24580-51-6; 4-allyl-4-valerolactone,69492-28-0; citral (R*,S*)-Pmethylhomoallyl alcohol, 83605-34-9; citral (R*,R*)-P-methylhomoallyl alcohol, 83605-35-0; citral, 5392-40-5; cyclohexanone, 108-94-1; 2-methylcyclohexanone, 583-60-8.
Electronic Structure of the Sillcon-Silicon Double Bond. Silicon-29 Shleidlng Anisotropy In Tetramesltyldlsilene Kurt W. Zllm, Davld M. Grant,' and Josef Mlchl'
i
I00
200
L _ _ _ _ I I _
-100
0
Chemical
Shift
300
200
d' L I00
- __ 3
I opm from T M S )
Figure 1. Solid-state 29Si NMR (left) and I3C NMR (right) spectra obtained by the cross-polarization technique. R stands for mesityl (2,4,6-(CH3)3C6H2).
culminating much matrix-isolation and gas-phase work that permitted direct spectroscopic observation of less stabilized members of the silene family? this secured the demise of the time-honored rule concerning the instability-or nonexistence-of multiple bonds involving silicon. In spite of this intense interest, relatively little is known as yet about the detailed nature of the Si=Si moiety. According to an X-ray structure analysis2 on 1, the four C-Si bonds are approximately coplanar (slightly antipyramidalized) and the %=Si distance is about 9 % shorter than the Si-Si distance in tetramesityldisilane (2) in good agreement with quantum mechanical calculations on Si2H4itself.8 This evidence suggests a fairly close analogy with the corresponding compounds of carbon.
Department of Chemistry, University of Utah Salt Lake City, Utah 84 112
H
H
Mark J. Fink and Robert West Department of Chemistry, University of Wisconsin Madison, Wisconsin 53706 Received August 10, 1982
Summary: The solid "Si NMR spectrum of tetramesityldisilene (a,,180, aZ227, and a33-15 ppm downfield from Me,Si) shows an anisotropy comparable to that of the solid 13Cspectrum of ethylene (all 234,aZ2120,and a3324 ppm downfield from Me,Si). The solid "Si NMR spectrum of tetramesityldisilane (all -37, aZ2-56, and a33 -72 ppm downfield from Me,Si) shows a much smaller anisotropy, similar to that in 13C spectra of alkanes. I t is concluded that the electronic structure of the Si=Si double bond bears a close resemblance to that of the C=C double bond.
Within a year, the r e p ~ r t l of - ~the remarkable stability of the first compound with a silicon-silicon double bond, tetramesityldisilene ( l ) ,was followed by two additional reports of disilene s y n t h e ~ e s . ~Along ~ ~ with the recent isolation of a compound with a carbon-silicon double bond6 (1)West, R.; Fink, M. J.; Michl, J. 15th Organosilicon Symposium, Duke University, Durham, NC, Mar 27-28,1981. (2)West, R.; Fink, M. J.: Michl, J. 6th International SvmDosium on Organosilicon Chemistry, Budapest, Hungary, Aug 23-29;1981. (3)West, R.; Fink, M. J.; Michl, J. Science (Washington,D.C.)1981, 214,1343. (4)Masamune, S.;Hanzawa, Y.; Murakami, S.; Bally, T.; Blount, J. F. J. Am. Chem. SOC.1982,104,1150. (5)Boudjouk, P.;Han, B.-H.; Anderson, K. R. J. Am. Chem. SOC.1982, 104,4992. (6)Brook, A. G.; Abdesaken, F.; Gutekunst, B.; Gutekunst, A.; Kallury, R. K. J. Chem. SOC.,Chem. Commun. 1981,191.
0276-7333/83/2302-Ol93$01.50/0
1
2
R = 2,4,6-(CH,),C,H,
We now wish to report the measurement of the anisotropy of the %Sichemical shift in 1. This probe of the finer details of electronic structure permits us to conclude that the Si=Si and C=C double bonds are indeed quite analogous even in intimate detail (Figure 1). The NMR chemical shift of a nucleus in a molecule is a function of the orientation of the molecule in the magnetic field. For ethylene (3) the principal values measured in parts per million downfield from Me4% are 24 for molecules aligned with their plane perpendicular to the magnetic field, 120 for molecules with the C=C bond aligned with the magnetic field, and 234 for molecules with their short in-plane axis aligned with the magnetic field.g For ethane (4), the difference of the chemical shifts for molecules whose C-C axis lies along the magnetic field and those whose C-C axis lies perpendicular to the magnetic (7)Chapman, 0.L.;Chang, C. C.; Kolc, J.; Jung, M. E.; Lowe, J. A.; Barton, T. J.; Turney, M. L. J. Am. Chem. SOC.1976,98,7844.Chedekel, M. R.; Skogland, M.; Kreeger, R. L.; Schechter, H. Ibid. 1976,98,7846. Nefedov, 0.M.; Mal'tsev, A. K.; Khabashesku, V. N.; Korolev, V. A. J. Organomet. Chem. 1980,201,123. Gusel'nikov, L. E.;Volkova, V. V.; Avakyan, V. G.; Nametkin, N. S. Ibid. 1980,201, 137. Mahaffy, P.G.; Gutowsky, R.; Montgomery, L. K. J . A m . Chem. SOC.1980,102,1854. Rosmus, P.;Bock, H.; Solouki, B.; Maier, G.; Mihm, G. Angew. Chem., Int. Ed. Engl. 1981,20,598.Maier, G.;Mihm, G.; Reisenauer, H. P. Ibid. 1981,20,597.Drahnak, T.J.; Michl, J.; West, R. J . Am. Chem. SOC.1981, 103, 1845. (8)Lischka, H.; Kohler, H.-J. Chem. Phys. Lett. 1982,85, 467 and references therein. (9)Zilm, K. W.; Grant, D. M.; Conlin, R. T.; Michl, J. J . Am. Chem. SOC.1978,100,8038.Zilm. K. W.;Conlin, R. T.: Grant, D. M.: Michl. J. Ibid. 1980,102,6672.
0 1983 American Chemical Society
