Structures of the Pentaphenylcyclopentadienyl Radical, (Pentaphenylcyclopentadienyl)tin(IV) Trichloride, and Bromo(chloro)bis(tetrahydrofuran)tin(II): Products of the Reaction of C₅Ph₅X with SnX₂ (X = Cl, Br)

Abstract

The reaction of SnCl2 with C5Ph5Cl produces C5Ph5SnCl3 (1) in an oxidative-addition reaction, while the pentaphenylcyclopentadienyl radical, C5Ph5•, (2) is obtained in the reactions of C5Ph5Br with SnCl2 or SnBr2 in diethyl ether/tetrahydrofuran (THF). In the reaction of SnCl2 with C5Ph5Br, one of the tin halide products was shown to be SnBrCl(THF)2 (3). The molecular structures of compounds 1−3 were determined by X-ray crystallography. Tin compound 1 is σ-bonded to the cyclopentadienyl ring; the radical 2 features a planar C5 ring, and the structure of 3 consists of SnBrCl units coordinated by two THF molecules with an apparent stereochemical activity of the tin lone pair.