SYNTHESIS AND STRUCTURE OF 1,4-DIBORYLCYCLOPENTADIENES

Bis(trimethylsilyl)cyclopentadiene reacts with two equivalents of boron halides to the bis(dihalogenoboryl)cyclopentadienes I, II and III. Reactions of I, II and III with tetramethyltin and dimethylamine yield the dimethyl- and bis(dimethylamino)-substituted compounds IV and V. The fluoro compound VI is synthesized by the reaction of III with arsenic trifluoride. Addition of pyridine to I and II yields the adducts VII and VIII. Structure and bonding properties of I-VIII are discussed by 1H-, 13C-, 11B- and 19F.n.m.r- and by i.r. and m.s. data. © 1979.