The reaction of cis and rans 2-iodomethyl 1-tosyloxycyclohexanes and 4-enes with nBuLi was studied and found to be stereospecific, the products being respectively bicyclo(4.1.0)hexane (ene) cis and methylene cyclohexane (ène). A parallel is drawn between this reaction and alkaline deshydrohalogenation of cyclic 1,2-halohydrins; a reaction pathway is proposed.
Tandem Cycloaddition Chemistry of Nitroalkenes: Preparative and Theoretical Studies on the Stereochemical Course of [3 + 2] Cycloaddition of Cyclic Nitronates
作者:Scott E. Denmark、Mark Seierstad、B. Herbert
DOI:10.1021/jo9818374
日期:1999.2.1
Intermolecular [3 + 2] cycloadditions between two cyclic nitronates and a series of dipolarophiles are examined. High facial selectivity is observed in all cases and is analyzed with the aid of ab initio transition structure calculations. Monosubstituted dipolarophiles reacted with exclusive regiocontrol. Disubstituted dipolarophiles reacted with varying degrees of regiocontrol, which was dependent