Metal carbonyl chemistry. Part XVI. Reactions of Prop-2-ynyl compounds with phosphine-substituted carbonylmanganese anions and methyl- and phenyl-pentacarbonylmanganese

Abstract

Prop-2-ynyl chloride forms stable σ-prop-2-ynyl complexes with the anions [Mn(CO)₄PPh₃]^– and [Mn(CO)₃(PPh₃)₂]^–. The compound [(CH⋮C·CH₂)Mn(CO)₄(PPh₃)] reacts with the acids RCO₂H (R = Me, Et, or ClCH₂) to afford stable 1 : 1 adducts of the type [{RCO·O·CH₂·(:CH₂)}Mn(CO)₄(PPh₃)], whereas the acids HX (X = Cl, Br, l or CF₃·CO₂) react to give [XMn(CO)₄(PPh₃)]. Sulphur dioxide also reacts with [{CH⋮C·CH₂}Mn(CO)₄(PPh₃)] to give the adduct O:[graphic omitted]CH. A number of stable (vinyl ketone)manganese carbonyl complexes, in which the keto-group is co-ordinated to the manganese atom, have been isolated from the reaction of methyl- and phenyl-pentacarbonylmanganese with prop-2-ynyl compounds.