Construction of cyclopentyl carbinols from ω-tosyloxy-1-alkenyl boronate esters and grignard reagents
Addition of RMgCl (R = n-Bu, Ph) to pinacol esters of 6-tosyloxy-l-alkenyl boronic acids at -78 °C gave the borates, which upon warming to room temperature underwent migration of R on boron to C(1) carbon and concomitant ring construction C-C bond formati