Reactions of trans-bis[1,2-bis(diphenylphosphino)ethane]bis(dinitrogen)-tungsten and -molybdenum with α-ω-dibromides, Br(CH2)nBr (n= 2–12)

Abstract

The reactions of trans-[M(N₂)₂(Ph₂PCH₂CH₂PPh₂)₂](M = Mo or W) with Br(CH₂)_nBr under irradiation in benzene solution yield products which are a function of n. For n= 3, complexes containing the group N₂(CH₂)₃Br are formed. For n= 4 or 5, complexes with rings N(CH₂)_n are formed and for n= 6–12 two series of complexes, containing either N₂(CH₂)_nN₂ or N₂(CH₂)_nBr are isolated. Members of the two series may be isolated as diazenido-complexes [MBr{N₂(CH₂)_nBr}(Ph₂PCH₂CH₂PPh₂)₂] or [{µ-N₂(CH₂)_nN₂}{MBr(Ph₂PCH₂CH₂PPh₂)₂}₂] respectively, both of which can be protonated reversibly to hydrazido(2–)-forms.