An anionic nucleophilic d4 carbyne complex.

The reaction of the methylidyne complex [W([triple bond, length as m-dash]CH)Br(CO)2(dcpe)] (dcpe = 1,2-bis(dicyclohexylphosphino)ethane) with tBuLi affords the intermediate anionic neopentylidyne complex Li[W([triple bond, length as m-dash]CtBu)(CO)2(dcpe)] which acts as a metal-based nucleophile towards tBuCl, tBuBr, Ph2E2 (E = S, Se, Te) and ClSnMe3 to afford the new carbyne complexes [W([triple bond, length as m-dash]CtBu)(X)(CO)2(dcpe)] (X = Cl, Br, EPh, SnMe3).