Reactions of metal carbonyls. Part V. Reaction of a series of substituted manganese carbonyl bromide compounds with nitrosonium hexafluorophosphate

Abstract

The reactions of NOPF₆ with [Mn(CO)₅Br] and cis-[Mn(CO)₄(PMe₂Ph)Br] in acetonitrile solution have given the cations [Mn(CO)₅(CH₃CN)]⁺ and cis-(Mn)(CO)₄[(PMe₂Ph)(CH₃CN)]⁺. Fac- and mer-trans-[Mn(CO)₃L₂Br]-[L = P(OMe)₃, PMe₃, PMe₂Ph and dpm] are oxidised by NOPF₆ to give the salts fac-[Mn(CO)₃ L₂Br]PF₆. Similar treatment of mer-cis-[Mn(CO)₂L₃Br][L = P(OMe)₃, P(OEt)₃, P(OMe)₂Ph, PMe₃ and PMe₂Ph] with NOPF₆ gave mer-cis-[Mn(CO)₂(PMe₃)₃Br]PF₆ and mer-trans-[Mn(CO)₂L₃Br]PF₆[L = P(OMe)₃, P(OEt)₃, P(OMe)₂Ph and PMe₂Ph]. Mer-trans-[Mn(CO)₂L₃Br]PF₆[L = P(OMe)₃, P(OEt)₃ and P(OMe)₂Ph] further react with L in refluxing chloroform to give the cations cis-[Mn(CO)₂ L₄]⁺. The reaction of cis-[Mn(CO)₂{P(OMe)₂Ph}₄]PF₆ with NOPF₆ gave the dipositive manganese(II) cation trans-Mn(CO)₂{[P(OMe)₂Ph}₄]²⁺ which is readily reduced by hydrazine to give trans-[Mn(CO)₂{P(OMe)₂ Ph}₄]⁺. The reaction of the tetrasubstituted complex [Mn(CO)-{P(OMe)₃}₄Br] with NOPF₆ gave [Mn(CO)(NO){P(OMe)₃}₄](PF₆)₂.