名称:
Backbone modified small bite-angle diphosphines: Synthesis and molecular structures of [M(CO)4{X2PC(R1R2)PX2}] (M=Mo, W; X=Ph, Cy; R1=H, Me, Et, Pr, allyl, R2=Me, allyl)
摘要:
A range of new small bite-angle diphosphine complexes, [M(CO)(4) {X2PC((RR2)-R-1)PX2}] (M = Mo, W; X = Ph, Cy; R-1 = H, Me, Et, Pr, allyl, R 2 = Me, allyl), have been prepared via elaboration of the methylene backbones in [M(CO)(4)(X2PCH2PX2)] as a result of successive deprotonation and alkyl halide addition. When X = Ph it proved possible to replace both methylene protons but for X = Cy only one substitution proved possible. This is likely due to the electron-releasing nature of the cyclohexyl groups but may also be due to steric constraints. Attempts to prepare the bis(allyl) substituted complex [Mo(CO)(4){Ph2PC(allyl)(2)PPh2}] were only moderately successful. The crystal structures of nine of these complexes are presented. (C) 2007 Elsevier B.V. All rights reserved.