Preparation of the isocyanide complexes trans-[ReCl(CNR)(dppe)2](R = Me or But) and their reactions with acid to give carbyne complexes. X-Ray crystal structure of trans-[ReCl(CNHMe)(dppe)2][BF4]

Abstract

The complexes trans-[ReCl(CNR)(dppe)₂](1, R = Me or Bu^t) have been prepared by replacement of dinitrogen in trans-[ReCl(N₂)(dppe)₂]. The alkyl isocyanide ligands in complexes (1) undergo electrophilic attack at the nitrogen atom by mineral acid (HBF₄), forming the carbyne complexes trans-[ReCl(CNHR)(dppe)₂][BF₄](2, R = Me or Bu^t) and spectroscopic data for these complexes are given.

The X-ray structure of trans-[ReCl(CNHMe)(dppe)₂][BF₄] has been determined and shows that the CNMe angle is 123(2)°, the Re–C (carbyne) bond length is 1.80(3)Å, and the C(carbyne)–N bond length is 1.35(3)Å.