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

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.