Synthesis, Crystal Structure, and Optical Properties of a

Synthesis, Crystal Structure, and Optical Properties of a Polyoxometalate-Based Inorganic−Organic Hybrid Solid, (n-Bu4N)2[Mo6O17(≡NAr)2] (Ar ...
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CRYSTAL GROWTH & DESIGN

Synthesis, Crystal Structure, and Optical Properties of a Polyoxometalate-Based Inorganic-Organic Hybrid Solid, (n-Bu4N)2[Mo6O17(≡NAr)2] (Ar ) o-CH3OC6H4)

2006 VOL. 6, NO. 1 253-257

Yun Xia,† Pingfan Wu,§ Yongge Wei,*,‡,| Yuan Wang,| and Hongyou Guo*,† Department of Chemistry, Beijing UniVersity of Chemical Technology, Beijing 100029, China, Department of Chemistry, Tsinghua UniVersity, Beijing 100084, China, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking UniVersity, Beijing 100871, China, and Department of Food Sciences, College of Bioengineering, Hubei UniVersity of Technology, Wuhan 430068, China ReceiVed August 3, 2005; ReVised Manuscript ReceiVed September 18, 2005

ABSTRACT: A novel organic-inorganic hybrid solid, (n-Bu4N)2[Mo6O17(NAr)2] (Ar ) o-CH3OC6H4) 1, has been prepared by refluxing of (n-Bu4N)2[Mo6O19] and appropriate o-anisidine in acetonitrile with N-N′-dicyclohexylcarbodiimide (DCC) as the dehydrating agent. Compound 1 has been characterized by single-crystal X-ray diffraction. Both of the two terminal o-anisidido ligands are linked, respectively, to an Mo atom of the hexamolybdate in a terminal fashion and exhibit an almost linear coordination mode of the MotN triple bond character. The two o-anisidido aryl rings on the hexamolybdate cluster lie in the cis position, allowing π-π stacking of phenyl ring among the anions. In the crystal, the cluster anions of 1 aggregate into an interesting 1D double chain along the a-axis through π-π stacking and C-H‚‚‚O hydrogen-bonding interactions. Compared to the hexamolybdate parent, this solid has a smaller optical band gap of 2.25 eV from UV-visible-near-IR reflectance spectroscopy studies. It has also been characterized by 1H NMR, IR, and UV/Vis spectroscopic techniques. Introduction Polyoxometalates (POMs) are remarkable for their molecular and electronic structural diversity and their significance in quite diverse disciplines, including catalysis, medicine, and materials science.1-5 These species also play an important role in the design of new materials with novel electronic, magnetic, and topological properties.6 Additionally, the functionalization of POMs (i.e., the replacement of one or several oxo ligands by other ligands) has drawn tremendous attention in the past decade, and recently a new area of interest is the design and fabrication of hybrid supramolecular arrays based on POM building blocks and various organic ligands.3,7-11 Among the functionalized POMs, organoimido derivatives have attracted particular interest because their properties can be tuned by strong dπ-pπ interactions in which the organic pπ electrons may extend their conjugation to the inorganic framework. Moreover, they provide a route to applications in supramolecular chemistry, which can be utilized as building blocks to construct more complicated POM-based organicinorganic hybrids. This modular building block approach brings rational design and structure control into the synthesis of organic-inorganic hybrids. As part of a broad program concentrated on POM-based organic-inorganic hybrids, a number of organoimido derivatives of Lindqvist type POMs such as the hexamolybdate ion, [Mo6O19]2-, the pentatungstenmolybdate ion, [MoW5O19]2-, and the hexatungstate ion, [W6O19]2-, have been synthesized via three types of reactions. These include reactions with phosphinimines,12,13 isocyanates,14 and aromatic amines.15 Several years ago, based on the latter type of reaction, one of us, together with his UMKC co-workers,16 developed an efficient and convenient reaction protocol to obtain the

arylimido derivatives of hexamolybdate and pentatungstenmolybdate using N,N′-dicyclohexylcarbodiimide (DCC) as the dehydrating agent. Very recently, we have also published a useful procedure for the synthesis of arylimido derivatives of hexamolybdate with a remote electron-withdrawing group such as a bromo or chloro group.17 However, most of the resulting organoimido derivatives are mono-functionalized,12-14a,14c,15b,16-20 and only a few bifunctionalized compounds have been obtained so far.14b,15a,18,21,22 In addition, aromatic amine ligands containing an electron-donating substituent on the benzene ring such as an alkyloxo group have rarely been exploited to construct organoimido derivatives of POMs.15b It can be expected that such POM-based inorganic-organic hybrids would have more colorful photophysical and electrochemical properties, compared to other organoimido derivatives, due to stronger electronic interactions between the inorganic POM cluster acceptors and the electron-pushing organic donors. Herein we hope to report a new bifunctionalized compound (n-Bu4N)2[Mo6O17(NAr)2] (Ar ) o-CH3OC6H4) 1, which was synthesized by the metathesis reaction of (n-Bu4N)2[Mo6O19] and o-anisidine with DCC as a dehydrating agent. Its molecular and crystal structures have been characterized by X-ray singlecrystal diffraction. Its 1H NMR and IR spectra, UV/Vis absorption and reflectance spectroscopy have also been studied. Compared to its parent compound, (n-Bu4N)2[Mo6O19], the photochemical band gap of 1 is obviously reduced, due to the incorporation of two strong electron-donating o-anisidido groups. This interesting discovery provides us a potential chance to make unique molecular semiconductors or conductors based on POM-organic hybrid materials. Experimental Procedures

* To whom correspondence should be addressed. (H.G.) E-mail: guohy@ mail.buct.edu.cn. (Y.W.) E-mail: [email protected]. † Beijing University of Chemical Technology. ‡ Tsinghua University. | Peking University. § Hubei University of Technology.

All the chemicals purchased were of analytical grade and used without further purification, except for acetonitrile, which was dried by refluxing in the presence of CaH2 and was distilled prior to use. (n-Bu4N)2[Mo6O19] was synthesized according to an improved literature method23 and was recrystallized from anhydrous acetone and dried under

10.1021/cg0503797 CCC: $33.50 © 2006 American Chemical Society Published on Web 11/11/2005

254 Crystal Growth & Design, Vol. 6, No. 1, 2006 Scheme 1. Synthesis of 1

vacuum before use. IR spectra were recorded in KBr pellets with a FT-IR NICOLET 210 spectrophotometer. UV/Vis absorption spectra were recorded in acetonitrile with a Shimadzu UV-2501PC spectrophotometer. 1H NMR spectra were recorded at 600.13 MHz at 298 K using a Bruker AV-600 instrument. Optical diffuse reflectance spectra were performed on a Shimadzu UV-3100 recording spectrophotometer with a Φ60 mm integrating sphere from 250 to 2500 nm at room temperature. Initially, the 100% line flatness of the spectrophotometer was set using barium sulfate (BaSO4). A powder sample of the compound was mounted on the sample holder. The thickness of the sample was approximately 2.00 mm, which was much larger than the size of the individual crystal particles.24 Synthesis of 1. To a 100 mL round-bottom flask were added anhydrous acetonitrile (50 mL), o-anisidine (0.22 mL, 2.0 mmol), (n-Bu4N)2[Mo6O19] (1.50 g, 1.1 mmol), and 1,3-dicyclohexylcarbodiimide (0.47 g, 2.3 mmol). The solution was warmed with a heating mantle and stirred mechanically. The reaction mixture was brought to reflux and held at the refluxing temperature for 12 h. The resulting dark red solution was then cooled to room temperature and allowed to stand for 2 h until a white precipitate of 1,3-dicyclohexylurea formed. The solution was filtered to remove 1,3-dicyclohexylurea and other insoluble materials. The filtrate was evaporated to give a viscous oil. This red oil was then washed with ethanol (10 mL), and the residue was resolved in acetone (60 mL). The crude crystalline product of 1 was obtained in about 65% yield within 3 days on the slow evaporation of acetone in the open air. X-ray quality single crystals were grown by the slow diffusion of ethanol into an acetone solution of the crude product in a test tube. Elemental analysis calc. (%) for C46H86Mo6N4O19: C 35.08, H 5.50, N 3.56; found C 35.02, H 5.57, N 3.92. 1H NMR (CD CN, 298 K): δ 7.26 (d, C H (o), 2H), 7.11 (t, C H (m), 3 6 4 6 4 2H), 7.03 (d, C6H4(m), 2H), 6.96 (t, C6H4(p), 2H), 3.93 (s, OCH3, 6H), 3.11 (t, NCH2, 16H), 1.61 (m, CH2, 16H), 1.37 (m, CH2, 16H), 0.98 ppm (t, CH3, 24H). IR (KBr:) ν˜ max ) 968 (m), 944 (s)[ν(MotO, MotN)], 794(s), 774(s) cm-1 [ν(MoOMo)]. UV/Vis (MeCN): λmax ) 368, 244 nm. Reflectance spectroscopy shows its optical energy gap of 2.25 eV. X-ray Crystallography. X-ray single-crystal diffraction data for a red sheetlike crystal of 1 with dimensions of 0.50 × 0.20 × 0.05 mm3 were collected on Bruker Smart Apex CCD diffractometer with graphite-monochromatized Mo KR radiation (λ ) 0.71073 Å) at room temperature (296 ( 2 K) in the range of 1.97 < θ < 26.00°. A total of 18 561 reflections were measured of which there are 11 733 unique reflections and 9093 observed reflections with the criterion of I g 2 σ(I). The raw data were corrected for LP factors and empirical absorption. The structure was solved by direct methods and refined anisotropically by full-matrix least squares on F2. The computations were performed using the SHELX97 program.25,26 All the drawings were generated with the XP program in the SHELXTL software package, version 5.10.27

Xia et al. Table 1. Crystal Data and Structure Refinement for Compound 1 empirical formula formula weight temperature wavelength crystal system space group unit cell dimensions V Z density (calculated) absorption coefficient F(000) crystal size theta range for data collection index ranges reflections collected independent reflections completeness to θ ) 26.00° max. and min. transmission refinement method data/restraints/parameters goodness-of-fit on F2 final R indices [I > 2σ(I)] R indices (all data) largest diff peak and hole

C46H86N4O19Mo6 1574.83 296(2) K 0.71073 Å triclinic P1h a ) 11.855(2) Å, R ) 79.08(3)° b ) 12.300(3) Å, β ) 80.31(3)° c ) 21.329(4) Å, γ ) 86.55(3)° 3008.9(11) Å3 2 1.738 Mg/m3 1.281 mm-1 1588 0.50 × 0.20 × 0.05 mm3 1.97 to 26.00° -14 e h e 14, -15 e k e 14, -26 e l e 26 18561 11733 [R(int) ) 0.0235] 99.2% 0.9387 and 0.5667 full-matrix least-squares on F2 11733/0/676 1.012 R1 ) 0.0369, wR2 ) 0.0853 R1 ) 0.0505, wR2 ) 0.0920 0.560 and -0.456 e Å-3

We presume that this difference results from the much higher nucleophilicity of o-anisidine than 4-iodo-2,6-dimethylaniline. Structures Description. A summary of the crystallographic data and structural determination for the compound 1 is provided in Table 1. Selected bond lengths and angles are listed in Table 2. An ORTEP viewing of the cluster anion is illustrated in Figure 1. In the cluster anion, the two o-methoxyphenylimido ligands are bound to terminal positions of the hexamolybdate in cis fashion, suggesting that the presence of an extant [NAr] group exerts an activating effect at proximal [MotO] sites. The short Mo-N bond distances of 1.734(3) and 1.737(3) Å and the C-N-Mo bond angles close to 180° (C(1)-N(1)-Mo(1), 165.8(3)° and C(8)-N(2)-Mo(2), 178.1(3)°) are typical of organoimido groups bonded at an octahedral d0 metal center and are consistent with a substantial degree of MotN triple

Results and Discussion Preparation of the Compound. As it is shown in Scheme 1, the reaction of (n-Bu4N)2[Mo6O19] with 2 equiv of o-anisidine in anhydrous acetonitrile in the presence of the dehydrating agent DCC afforded a red crystalline product of 1 in good yield of about 65%. As it was observed, there were scarcely mono- or multi-functionalized imido derivatives formed from this procedure except for a little salt of the β-octamolybdate. This result is quite different from previous observations for the reaction of (n-Bu4N)2[Mo6O19] with 2 equiv of 4-iodo-2,6-dimethylaniline,16a which usually gives a mixture of monosubstituted, disubstituted, and even polysubstituted organoimido derivatives. However, in our experiment, we also found that 1 could be obtained together with the corresponding monofunctionalized derivative when (n-Bu4N)2[Mo6O19] was allowed to react with 1 equiv of o-anisidine in anhydrous acetonitrile for a longer refluxing time.

Figure 1. ORTEP viewing of the cluster anion, [Mo6O17(NAr)2]2- (Ar ) o-CH3OC6H4), with atomic labeling scheme. Thermal ellipsoids are drawn at the 50% probability level.

Polyoxometalate-Based Inorganic-Organic Hybrid Solid

Crystal Growth & Design, Vol. 6, No. 1, 2006 255

Table 2. Selected Bond Lengths [Å] and Angles [°] for Compound 1 Mo(1)-N(1) Mo(1)-O(9) Mo(1)-O(7) Mo(1)-O(12) Mo(1)-O(11) Mo(1)-O(1) Mo(2)-N(2) Mo(2)-O(10) Mo(2)-O(17) Mo(2)-O(9) Mo(2)-O(15) Mo(2)-O(1) Mo(3)-O(3) Mo(3)-O(8) Mo(3)-O(10) Mo(3)-O(7) Mo(3)-O(2) Mo(3)-O(1) Mo(4)-O(4) Mo(4)-O(11) Mo(4)-O(15) Mo(4)-O(13) Mo(4)-O(14) Mo(4)-O(1) Mo(5)-O(5) Mo(5)-O(12) Mo(5)-O(13) Mo(5)-O(16) Mo(5)-O(2) Mo(5)-O(1) Mo(6)-O(6) Mo(6)-O(17) Mo(6)-O(14) Mo(6)-O(16) Mo(6)-O(8) Mo(6)-O(1) O(19)-C(2) O(19)-C(7) O(18)-C(9) O(18)-C(14) N(1)-C(1) N(2)-C(8) C(1)-N(1)-Mo(1) C(8)-N(2)-Mo(2)

1.734(3) 1.910(2) 1.919(2) 1.980(3) 1.985(2) 2.221(2) 1.737(3) 1.940(2) 1.940(2) 1.949(2) 1.968(2) 2.233(2) 1.688(3) 1.910(3) 1.913(2) 1.925(2) 1.928(3) 2.348(2) 1.687(3) 1.880(3) 1.905(2) 1.952(3) 1.966(3) 2.336(2) 1.691(3) 1.877(3) 1.914(3) 1.928(3) 1.939(3) 2.387(2) 1.684(3) 1.897(2) 1.907(3) 1.914(3) 1.945(3) 2.377(2) 1.347(5) 1.425(5) 1.352(5) 1.438(5) 1.385(5) 1.379(4) 165.8(3) 178.1(3)

bond character.28 Compared to the hexamolybdate and other organoimido derivatives, the bond lengths of the four terminal oxo ligands of 1 do not vary appreciably. It was noticed that the central oxygen atom has an important function in stabilizing the hexamolybdate cage.19 The distances between Mo(1), Mo(2), and the central O(1) atom (Mo(1)-O(1) and Mo(2)O(1)) are 2.221(2) Å, 2.233(2) Å, respectively, which are almost the same and significantly shorter than the other four Mo-O(1) distances (2.348(2), 2.336(2), 2.377(2), 2.387(2) Å). It implies that the central O(1) atom is closer to the imido-bearing Mo atoms in this organoimido derivative and is in agreement with the weaker trans-influence of the organoimido group than a terminal oxo group. Such a contraction has also been observed in the structures of previously reported organoimido derivatives of Lindqvist polyoxometalates.12-18,20-22,29 Considerable variations are seen in the bond lengths involving the doubly bridging oxygen atoms, which is again consistent with other imido derivatives of Lindqvist polyoxometalates reported in the literatures.12-18,20-22,29 Within the crystal lattice of 1, there is the supramolecular dimerization of the cluster anions of 1 through π-π stacking between the parallel phenyl rings attached to Mo(1) and Mo(1)i (symmetry code i: 1 - x, -y, 1 - z) atoms on two neighboring hexamolybdate cluster anions. This dimerization is further boosted by a pair of parallel C-H‚‚‚O hydrogen bondings (C(11)-H(11)‚‚‚O(6)i, 3.770 Å, 169.6°. symmetry

Figure 2. Dimeric structure of the cluster anion of 1.

Figure 3. 1D aggregate of the cluster anion of 1 in the crystal.

code i: 1 - x, -y, 1 - z) between the C-H groups, C(11)H(11) and C(11)i-H(11)i, of the parallel phenyl rings, and two terminal oxygen atoms of the two cluster anions, O(6)i and O(6), respectively (Figure 2). These stacking interactions just explain the significant compression of the C(1)-N(1)-Mo(1) angle compared to the C(8)-N(2)-Mo(2) angle. The existence of supramolecular π-π interactions between the pairs of cluster anions is clearly indicated by the short vertical phenyl ring separation of 3.3599 Å. Such an interesting structural feature has just been mentioned recently in several phenylimido derivatives of hexamolybdate.17,21,22 Besides the above aromatic H atom, H(11), three methyl hydrogen atoms, H(7c), H(14a), and H(14c), of two methoxy groups of the cluster anion of 1 also involve the C-H‚‚‚O hydrogen bondings in the crystal. A pair of parallel C-H‚‚‚O hydrogen bondings (C(14)-H(14a)‚‚‚O(18)ii and C(14)iiH(14a)ii‚‚‚O(18), 3.567 Å, 155.0°. symmetry code ii: -x, -y, 1 - z) between two neighboring methoxy groups, which form a six-membered hydrogen bonding ring, together with another pair of parallel C-H‚‚‚O hydrogen bondings (C(14)H(14c)‚‚‚O(3)ii and C(14)ii-H(14c)ii‚‚‚O(3), 3.648 Å, 148.2°. symmetry code ii: -x, -y, 1 - z) assemble the above dimers into an interesting 1D double chain of the hybrid inorganic clusters with a sandwiched organic chain along the a-axis (Figure 3). Such chains are further stabilized by the C-H‚‚‚O hydrogen bonding between the C-H group, C(7)-H(7c), belonging to the benzene ring which does not involve π-π stacking and a bridging oxygen atom, O(14)iii, of a neighboring cluster anion within the chain (C(7)-H(7c)‚‚‚O(14)iii, 3.554 Å, 162.8°; symmetry code iii: x - 1, y, z). Spectroscopic Characterization. In the low-wavenumber region of the IR spectra (ν˜ < 1000 cm-1), compound 1 displays similar characteristic patterns of the Lindqvist structure.30

256 Crystal Growth & Design, Vol. 6, No. 1, 2006

Actually, the IR bands of the aniline ligand in this region (mostly γ(C-C and C-H)) are of low intensity with respect to those of the polyoxometalate framework. Compound 1 presents more complex features than (n-Bu4N)2[Mo6O19], especially in the 1000-700 cm-1 region of the characteristic band of Mo-O stretching vibrations. In particular, the strong νas(Mo-Ot) band observed at 958 cm-1 in (n-Bu4N)2[Mo6O19]30 splits into two more or less resolved bands (∆ν˜ ≈ 20 cm-1) in the arylimido derivatives. Similarly, the broad and strong band observed at 797 cm-1 of the parent hexamolybdate, which was assigned to a Mo-Ob stretching mode, also splits into two components (∆ν˜ ≈ 20 cm-1) in compound 1. Such splittings have been ascribed to the reduction in symmetry of the hexamolybdate framework from Oh to C2V upon the substitution of MotO by MotNAr. In the approximation of separate Mo-Ot and Mo-N vibrations, the stronger band, at low energy (ν˜ ≈ 944 cm-1) should be assigned to the νas(Mo-Ot) mode, whereas the less intense band, a shoulder peak, (ν˜ ≈ 968 cm-1) might associate principally with the Mo-N vibrator.13,15b In compound 1, the aromatic ν(C-H) bands (ν˜ > 3000 cm-1) are hardly visible, due to their low intensity, and the complex pattern around 2900 cm-1 contains aliphatic ν(C-H) bands both of the tetrabutylammonium cation and of the substituent on the aromatic ring. The IR spectra of compound 1 differs markedly in its band positions but also in their intensities in the mediumfrequency region (1650-1000 cm-1) where ν(C-N) and various bands from the o-anisidine occur. The band in the region of 1623, 1579, 1480 cm-1 was shown to be ν(CdC) of benzene mode; 1380 and 1244 cm-1 were assigned to δ(C-H) of methyl and ν(C-O) of aromatic ether, respectively; 1333, 1277 cm-1 was thought to be associated with ν(C-N) of the arylimido. The 1H NMR spectrum (in CD3CN) of compound 1 shows clearly resolved signals, all of which can be unambiguously assigned. The integration matches well with the assumed structure. Compared to the 1H NMR spectrum of the corresponding free o-anisidine, the protons of aromatic and methoxy exhibit significantly downfield chemical shifts, indicating the much weaker shielding nature of [Mo5O18(MotN-)]2- than the amino group NH2-. In addition, we also notice that there is a well-resolved signal at 3.93 ppm, which is attributable to the methoxy proton of the aryl ring. By comparing integral values of ligand resonances to integral values of the n-tetrabutylammonium ion resonances, the extent of organoimido substitution, i.e., the ratio of ligand to hexamolybdate, can be easily quantified. In this way, we were able to determine that 1 has a ligand to hexamolybdate ion ratio of approximately 2:1, consistent with 1 being the bifunctionalized product. Figure 4 shows the UV/Vis absorption spectra of the tetrabutylammonium salts of [Mo6O19]2- and compound 1. The lowest energy electronic transition at 325 nm in [Mo6O19]2was assigned to a charge-transfer transition from the terminal oxygen nonbonding π-type HOMO to the molybdenum π-type LUMO, which is bathochromically shifted by about 40 nm and becomes considerably more intense in compound 1 (368 nm) due to the strong electron-donating ability of methoxyl group attached to the benzene ring, indicating that the Mo-N π-bond is formed in these organoimido derivatives.12,31 In other words, there is a strong electronic interaction between the hexamolybdate cluster and the organic conjugated ligands. Study of Optical Band Gap. To explore conductivity of the compound 1, the measurement of diffuse reflectivity for a powder sample was used to obtain its band gap (Eg), which agrees rather well with that obtained by absorption measurements from the single crystal. The band gap (Eg) was determined

Xia et al.

Figure 4. UV/Vis absorption spectra of [n-Bu4N]2[Mo6O19] and compound 1.

Figure 5. K-M function versus energy (eV) curve of [n-Bu4N]2[Mo6O19] and compound 1.

as the intersection point between the energy axis and the line extrapolated from the linear portion of the absorption edge in a plot of Kubelka-Munk function F against energy E.32,33 Kubelka-Munk function, F ) (1 - R)2/2R, was converted from the recorded diffuse reflectance data, where R is the reflectance of an infinitely thick layer at a given wavelength. The F versus E plot, as shown in Figure 5, a steep absorption edge is displayed, from which the Eg can be assessed at 2.25 eV. The reflectance spectrum measurement reveals the presence of an optical band gap and the nature of semiconductivity with a large energy gap for 1. The Eg of 1 is smaller than that of the tetrabutylammonium salts of [Mo6O19]2- (Eg ) 2.68 eV) shown in Figure 4a, which also indicates that the formation of the Mo-N π-bond and the delocalization of π electrons from the conjugated oraganoimido ligand to the metal oxygen cluster in compound 1 reduce remarkably the energy level difference between the oxygen π-type HOMO and the molybdenum π-type LUMO compared to [Mo6O19]2-. Conclusions A novel cis-bifunctionalized organoimido derivative, (nBu4N)2[Mo6O17(NAr)2] (Ar ) o-CH3OC6H4) has been prepared, in 65% good yield, by the metathesis of the hexamolybdate ion and o-anisidine with DCC as a dehydrating agent in dry

Polyoxometalate-Based Inorganic-Organic Hybrid Solid

acetonitrile. This compound belongs to the family of Linqvisttype polyoxometalates. Compared to the parent hexamolybdate, it has a smaller optical band gap of 2.25 eV, observed usually in a semiconductor, which suggests that the optical band gap of polyoxometalates could be tuned effectively and controllably via chemical modification using suitable organic ligands. Interestingly, in the solid state, two of its cluster anions form a dimer via π-π stacking using one phenyl ring of each cluster, and the dimers are further linked by various C-H‚‚‚O hydrogenbonding interactions into a 1D chain. This kind of supramolecular assembly together with its semiconductivity implies that such organoimido derivatives have potential applications in polyoxometalate-based organic-inorganic hybrid conducting materials. Acknowledgment. This work is sponsored by NFSC No. 20201001, SRF for ROCS of SEM, MOST No. TG2000077503, and the university funding from Hubei University of Technology. Supporting Information Available: X-ray crystallographic CIF file for the compound 1. This material is available free of charge via the Internet at http://pubs.acs.org.

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