Reactions of tin halides with {(π-dienyl)Fe(CO)2}2 compounds

Abstract

The products of the reactions of {(π-dienyl)Fe(CO)₂}₂ with SnX₂(dienyl = C₅H₅, MeC₅H₄, or C₉H₇; X = F, Cl, Br, or I) may be {(π-dienyl)Fe(CO)₂X}, {(π-dienyl)Fe(CO)₂SnX₃}, {(π-dienyl)Fe(CO)₂}₂SnX₂, or {(π-dienyl)-Fe(CO)₂}₃SnX depending on X, the reaction conditions, and the mole ratio of reactants. It is suggested that when X = F or Cl, the insertion of SnX₂ into the Fe–Fe bonds takes place largely in one step giving the {(π-dienyl)Fe-(CO)₂}₂SnX₂ derivatives. However, when X = Br or l, the dimers are first converted to a mixture of {(π-dienyl)-Fe(CO)₂X}, and {(π-dienyl)Fe(CO)₂SnX₃}. The second of these reacts further with excess dimer to give the ‘insertion’ products. The reactions of {(π-dienyl)′Fe(CO)₂}₂ with {(π-dienyl)Fe(CO)₂SnX₃} or {(π-dienyl)Fe-(CO)₂}₂SnX₂ may be used to prepare {(π-dienyl)Fe(CO)₂}{(π-dienyl)′Fe(CO)₂}SnX₂ and {(π-dienyl)Fe(CO)₂}₂{(π-dienyl)′Fe(CO)₂}SnX respectively. The tin(IV) halides, with the exception of the fluoride, react readily with the dimers to give a similar variety of products.