Reactions of the Dirhenium(II) Complexes Re2X4(dppm)2 (X = Cl, Br; dppm = Ph2PCH2PPh2) with Isocyanides. 10.1 Synthesis and
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- 作者：Wengan Wu ; Phillip E. Fanwick ; and Richard A. Walton
- 刊名：Inorganic Chemistry
- 出版年：1996
- 出版时间：September 11, 1996
- 年：1996
- 卷：35
- 期：19
- 页码：5484 - 5491
- 全文大小：346K
- 年卷期：v.35,no.19(September 11, 1996)
- ISSN：1520-510X
文摘
The reactions of the unsymmetrical, coordinatively unsaturateddirhenium(II) complexes[Re2Br3(
-dppm)2(CO)(CNXyl)]Y (XylNC = 2,6-dimethylphenyl isocyanide; Y =O3SCF3 (3a), PF6(3b)) with XylNC afford at leastthree isomeric forms of the complex cation[Re2Br3(-dppm)2(CO)(CNXyl)2]+.Two forms have very similarbis(-halo)-bridged edge-sharing bioctahedral structures of thetype[(CO)BrRe(-Br)2(-dppm)2Re(CNXyl)2]Y(Y = O3SCF3(4a/4a'), PF6(4b/4b')), while the third is an openbioctahedron[(XylNC)2BrRe(-dppm)2ReBr2(CO)]Y(Y = O3SCF3 (5a),PF6 (5b)). While the analogous chlorocomplex cation[Re2Cl3(-dppm)2(CO)(CNXyl)2]+was previously shown to exist in three isomeric forms, only one ofthese has been found to be structurally similarto the bromo complexes (i.e. the isomer analogous to 5a and5b). The reaction of 3a with CO gives thesalt[Re2Br3(-dppm)2(CO)2(CNXyl)]O3SCF3(7), in which the edge-sharing bioctahedral cation[(XylNC)BrRe(-Br)(-CO)(-dppm)2ReBr(CO)]+has an all-cis arrangement of 
-acceptor ligands. The Re-Redistances in thestructures of 4b', 5a, and7 are 3.0456(8), 2.3792(7), and 2.5853(13)Å, respectively, and accord with formalRe-Re bond orders of 1, 3, and 2, respectively. Crystal data for[Re2Br3(-dppm)2(CO)(CNXyl)2](PF6)0.78(ReO4)0.22·CH2Cl2(4b') at 295 K: monoclinic space groupP21/n (No. 14) with a =19.845(4) Å, b =16.945(5) Å, c = 21.759(3) Å, 
=105.856(13)
, V = 7038(5) Å3, andZ = 4. The structure was refined toR= 0.060 (Rw = 0.145) for 14 245 data(Fo2 >2
(Fo2)). Crystal data for[Re2Br3(-dppm)2(CO)(CNXyl)2]O3SCF3·C6H6 (5a) at 173K: monoclinic space group P21/n(No. 14) with a = 14.785(3) Å, b =15.289(4) Å, c =32.067(5) Å, = 100.87(2), V=7118(5) Å3, and Z = 4. Thestructure was refined to R = 0.046(Rw = 0.055)for 6962 data (I > 3.0(I)). Crystaldata for[Re2Br3(-dppm)2(CO)2(CNXyl)]O3SCF3·Me2CHC(O)Me(7) at295 K: monoclinic space group P21/n(No. 14) with a = 14.951(2) Å, b =12.4180(19) Å, c = 40.600(5) Å,= 89.993(11), V = 7537(3) Å3,and Z = 4. The structure was refined to R= 0.074 (Rw = 0.088) for 6595data(I > 3.0(I)).
-dppm)2(CO)(CNXyl)]Y (XylNC = 2,6-dimethylphenyl isocyanide; Y =O3SCF3 (3a), PF6(3b)) with XylNC afford at leastthree isomeric forms of the complex cation[Re2Br3(-dppm)2(CO)(CNXyl)2]+.Two forms have very similarbis(-halo)-bridged edge-sharing bioctahedral structures of thetype[(CO)BrRe(-Br)2(-dppm)2Re(CNXyl)2]Y(Y = O3SCF3(4a/4a'), PF6(4b/4b')), while the third is an openbioctahedron[(XylNC)2BrRe(-dppm)2ReBr2(CO)]Y(Y = O3SCF3 (5a),PF6 (5b)). While the analogous chlorocomplex cation[Re2Cl3(-dppm)2(CO)(CNXyl)2]+was previously shown to exist in three isomeric forms, only one ofthese has been found to be structurally similarto the bromo complexes (i.e. the isomer analogous to 5a and5b). The reaction of 3a with CO gives thesalt[Re2Br3(-dppm)2(CO)2(CNXyl)]O3SCF3(7), in which the edge-sharing bioctahedral cation[(XylNC)BrRe(-Br)(-CO)(-dppm)2ReBr(CO)]+has an all-cis arrangement of -acceptor ligands. The Re-Redistances in thestructures of 4b', 5a, and7 are 3.0456(8), 2.3792(7), and 2.5853(13)Å, respectively, and accord with formalRe-Re bond orders of 1, 3, and 2, respectively. Crystal data for[Re2Br3(-dppm)2(CO)(CNXyl)2](PF6)0.78(ReO4)0.22·CH2Cl2(4b') at 295 K: monoclinic space groupP21/n (No. 14) with a =19.845(4) Å, b =16.945(5) Å, c = 21.759(3) Å, =105.856(13), V = 7038(5) Å3, andZ = 4. The structure was refined toR= 0.060 (Rw = 0.145) for 14 245 data(Fo2 >2(Fo2)). Crystal data for[Re2Br3(-dppm)2(CO)(CNXyl)2]O3SCF3·C6H6 (5a) at 173K: monoclinic space group P21/n(No. 14) with a = 14.785(3) Å, b =15.289(4) Å, c =32.067(5) Å, = 100.87(2), V=7118(5) Å3, and Z = 4. Thestructure was refined to R = 0.046(Rw = 0.055)for 6962 data (I > 3.0(I)). Crystaldata for[Re2Br3(-dppm)2(CO)2(CNXyl)]O3SCF3·Me2CHC(O)Me(7) at295 K: monoclinic space group P21/n(No. 14) with a = 14.951(2) Å, b =12.4180(19) Å, c = 40.600(5) Å,= 89.993(11), V = 7537(3) Å3,and Z = 4. The structure was refined to R= 0.074 (Rw = 0.088) for 6595data(I > 3.0(I)).