Asymmetric organocatalytic Strecker-type reactions of aliphatic N,N-dialkylhydrazones
作者:Aurora Martínez-Muñoz、David Monge、Eloísa Martín-Zamora、Eugenia Marqués-López、Eleuterio Álvarez、Rosario Fernández、José M. Lassaletta
DOI:10.1039/c3ob41437j
日期:——
The enantioselective organocatalytic Strecker-type reaction of aliphatic N,N-dialkylhydrazones is presented. Using trimethylsilyl cyanide (TMSCN) as the cyanide source, the reaction can be efficiently catalyzed by a tert-leucine-derived bifunctional thiourea to afford the corresponding hydrazino nitriles in good to excellent yields (50–96%) and moderate to good enantioselectivities, up to 86% ee. Further
提出了脂族N,N-二烷基hydr的对映选择性有机催化Strecker型反应。使用三甲基甲硅烷基氰化物(TMSCN)作为氰化物源,可以由叔亮氨酸衍生的双官能硫脲有效地催化反应,从而以高至优异的收率(50-96%)和中等至良好的对映选择性获得相应的肼基腈。到86%ee。腈官能团的进一步转化允许获得有用的受保护的肼基酸和咪唑烷酮。有趣的是,某些肼基腈及其衍生物可以高回收率重结晶,从而产生基本纯的对映异构体。