Some complexes containing carbon chains end-capped by M(CO)2Tp′ [M = Mo, W; Tp′ = HB(pz)3, HB(dmpz)3] groups

Complexes M(CCCSiMe3)(CO)2Tp′ (Tp′ = Tp [HB(pz)3], M = Mo 2, W 4; Tp′ = Tp∗ [HB(dmpz)3], M = Mo 3) are obtained from M(CCCSiMe3)(O2CCF3)(CO)2(tmeda) (1) and K[Tp′].Reactions of 2 or 4 with AuCl(PPh3)/K2CO3 in MeOH afforded M{CCCAu(PPh3)}(CO)2Tp′ (M = Mo 5, W 6) containing C3 chains linking the Group 6 metal and gold centres.In turn, the gold complexes react with Co3(μ3-CBr)(μ-dppm)(CO)7 to give the C4-bridged {Tp(OC)2M}CCCC{Co3(μ-dppm)(CO)7} (M = Mo 7, W 8), while Mo(CBr)(CO)2Tp∗ and Co3{μ3-C(CC)2Au(PPh3)}(μ-dppm)(CO)7 give {Tp∗(OC)2Mo}C(CC)2C{Co3(μ-dppm)(CO)7} (9) via a phosphine-gold(I) halide elimination reaction. The C3 complexes Tp′(OC)2MCCCRu(dppe)Cp∗ (Tp′ = Tp, M = Mo 10, W 11; Tp′ = Tp∗, M = Mo 12) were obtained from 2–4 and RuCl(dppe)Cp∗ via KF-induced metalla-desilylation reactions. Reactions between Mo(CBr)(CO)2Tp∗ and Ru{(CC)nAu(PPh3)}(dppe)Cp∗ (n = 2, 3) afforded {Tp∗(OC)2Mo}C(CC)n{Ru(dppe)Cp∗} (n = 2 13, 3 14), containing C5 and C7 chains, respectively. Single-crystal X-ray structure determinations of 1, 2, 7, 8, 9 and 12 are reported.

Reactions of M{CCCAu(PPh3)}(CO)2Tp′ (M = Mo 5, W 6) with Co3(μ3-CBr)(μ-dppm)(CO)7 give the C4-bridged {Tp(OC)2M}CCCC{Co3(μ-dppm)(CO)7} (M = Mo 7, W 8), while Mo(CBr)(CO)2Tp∗ and Co3{μ3-C(CC)2Au(PPh3)}(μ-dppm)(CO)7 give {Tp∗(OC)2Mo}C(CC)2C{Co3(μ-dppm)(CO)7} (9).The C3 complexes Tp′(OC)2MCCCRu(dppe)Cp∗ (Tp′ = Tp, M = Mo 10, W 11; Tp′ = Tp∗, M = Mo 12) were obtained from 2–4 and RuCl(dppe)Cp∗ via KF-induced metalla-desilylation reactions, while reactions between Mo(CBr)(CO)2Tp∗ and Ru{(CC)nAu(PPh3)}(dppe)Cp∗ (n = 2, 3) afforded {Tp∗(OC)2Mo}C(CC)n{Ru(dppe)Cp∗} (n = 2 13, 3 14), respectively.Figure optionsDownload as PowerPoint slide