Stereochemical fate of an asymmetric migrating group in the pinacol rearrangement
作者:J. J. Beggs、M. B. Meyers
DOI:10.1039/j29700000930
日期:——
The optically active pinacol, (4S)-2,3,4-trimethylhexane-2,3-diol (I) was synthesized from (–)-(S)-2-methyl-butan-1-ol (III) and rearranged to (+)-3,3,4-trimethylhexan-2-one (II), which was degraded to (–)-2,2,3-tri-methylpentanoic acid (XI). The acid (XI) obtained by this method has a specific rotation and circular dichroism experimentally equal to that of (–)-(S)-2,2,3-trimethylpentanoic acid synthesized
光学活性频哪醇,(4 S)-2,3,4-三甲基己烷-2,3-二醇(I)由(-)-(S)-2-甲基-丁烷-1-醇(III)和重排为(+)-3,3,4-三甲基己-2-酮(II),后者降解为(-)-2,2,3,3-三甲基戊酸(XI)。通过这种方法获得的酸(XI)具有比旋光性和圆二色性,实验上与通过(+)-(S -1 )的二烷基化反应合成的(-)-(S)-2,2,3-三甲基戊酸是相同的-氰基-2-甲基丁烷(XIII),表明在(I)至(II)的重排中,不对称迁移基团[(S)-s-丁基]经历了迁移,并完全保留了构型。