On the origins of diastereoselectivity in the alkylation of diketopiperazine enolates
作者:Steven D. Bull、Stephen G. Davies、A. Christopher Garner、Alastair L. Parkes、Paul M. Roberts、Thomas G. R. Sellers、Andrew D. Smith、Juan A. Tamayo、James E. Thomson、Richard J. Vickers
DOI:10.1039/b701628j
日期:——
levels of diastereoselectivity are observed for benzylation of the lithium enolates of (S)-N,N′-bis-para-methoxybenzyl-3-iso-propyl-piperazine-2,5-dione, (S)-N(1)-para-methoxybenzyl-N(4)-methyl-3-iso-propyl-piperazine-2,5-dione and (S)-N(1)-methyl-N(4)-para-methoxybenzyl-3-iso-propyl-piperazine-2,5-dione. These data suggest that the high diastereofacial selectivity observed for alkylation of these diketopiperazine
高水平 非对映选择性 观察到烯醇锂的苄基化 (小号) - ñ,Ñ ' -双-对甲氧基苄基-3-异丙基-哌嗪-2,5-二酮, (小号) - Ñ(1) -对-methoxybenzyl- Ñ(4) -甲基-3-异丙基-哌嗪-2,5-二酮 和 (小号) - Ñ(1) -甲基- Ñ(4) -对甲氧基苄基-3-异丙基-哌嗪-2,5-二酮。这些数据表明,对于这些二酮哌嗪的烷基化模板观察到的高选择性diastereofacial主要的立体化学信息从C(3)到C(6)中继的结果经由1,2-扭转应变的由引入的影响Ñ -烷基取代基,而不是仅通过最小化空间相互作用来实现。