?-Alkynyl complexes of Manganese as ligands. Preparation, crystal structure and reactivity of > (Cy = cyclohexyl)

Article abstract of DOI:10.1016/0022-328X(88)83008-0

The reaction of the alkynyl complex cis- (I) with in hexane gives the compound <<μ-PhCCMn(CO)4(PCy3)>> (II) in which, as revealed by an X-ray diffraction study, the PCy3 ligand is trans to the CCPh group.Oxidation of II with in CH2Cl2 gives the alkynyl complex trans- , (III), which on standing in solution isomerizes to the cis isomer I.Reactions of II with Na under a CO atmosphere or with Ce(SO4)2 give mixtures of I and II.