ИСТИНА

We have shown earlier that the outcome in the reaction between cationic manganese carbynes [Cp(CO)2Mn≡С-R]X and dppm is governed by the nature of R substituent at the carbyne carbon atom.1 When R is Me or CH2Ph, phosphinoketene complexes [Cp(CO)Mn{η3-(P,C,C)-Ph2PCH2‒+PPh2‒C(R)=C=O}]X result from nucleophilic addition of the phosphorus atom to the carbyne carbon followed by coupling of the phosphoniocarbene and carbonyl ligands. At the same time, the relative arylcarbyne complexes [Ср(СО)2Mn≡С‒Ar]X (Ar = Ph, Tol) react with dppm to form λ5-1,3-diphosphetium semi-ylides. We studied the reaction of dppm with benzylcarbyne complexes of manganese [Cp*(CO)2Mn≡C-CH2Ph]BF4 (Mn2) and rhenium [Cp(CO)2Re≡C-CH2Ph]BF4 (Re2) obtained by protonation of the corresponding vinylidene precursors Cp*(CO)2Mn=C=C(H)Ph (Mn1) and Cp(CO)2Re=C=C(H)Ph (Re1) and found this reaction to afford phosphinoketene complexes [Cp*(CO)Mn{η3-(P,C,C)-Ph2PCH2‒+PPh2‒C(CH2Ph)=C=O}]BF4 and [Cp(CO)Re{η3-(P,C,C)-Ph2PCH2‒+PPh2‒C(CH2Ph)=C=O}]BF4.