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Treatment of the nucleophilic organotitanium derivative in Scheme I with electrophiles other than the proton should provide a route to bifunctional cyclopentane derivatives. To demonstrate this approach we treated two of the product mixtures with iodine.The iodoalcohol 7 was isolated in isomerically pure form (as the tert-butyldimethylsilyl ether) in 63% yield. In contrast, the cisorganotitanium intermediate in eq 5 cyclized to tetrahydrofuran 8 in 52% isolated yield. In both cases other isomeric products were presumably formed but were not isolated. E 'E 8We acticipate that this reaction, while quite useful in its own right, may also be the prototype for other novel transformations based on transition-metal-centered radicals.'* As a first step in this direction we plan to explore intermolecular additions of epoxides to activated olefins. Supplementary Material Available:Details of isolation and characterization (13C NMR, 'H NMR, HRMS, elemental analysis) of products 1-8 (4 pages). Ordering information is given on any current masthead page.(1 1) Other radical routes from carbohydrates to chiral cyclopentanes: Wilcox, C. S.; Gaudino, J. J. J. Am. Chem. SOC. 1986, 108, 3102-3104. RajanBabu, T. V. J . Am. Chem. SOC. 1987, 109, 609-611.(12) Roskamp and Pedersen have reported that another d' complex, NbCI,(THF)*, promotes an unprecedented dimerization of silylimines and nitriles to vicinal diamines. However, they note that 5-hexenenitrile is not cyclized suggesting that there is no long-lived carbon radical associated with the system: Roskamp, E. J.; Pedersen, S. F.

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