Synthesis of Optically Pure Highly Functionalized γ-Lactams via 2-Azetidinone-Tethered Iminophosphoranes
作者:Benito Alcaide、Pedro Almendros、Jose M. Alonso
DOI:10.1021/jo035623k
日期:2004.2.1
mesylates, which by exposure to sodium azide afforded the corresponding azides. Treatment of β-lactams bearing an azido side chain with triphenylphosphine (TPP) gave λ5-phosphazenes (iminophosphoranes, phosphine imines), which were not isolated. The sodium methoxide promoted reaction of the phosphazene β-lactams smoothly provided γ-lactams, through a N1−C2 bond breakage process on the four-membered lactam
已经开发了以2-氮杂环丁酮系链的亚氨基正膦为原料的光学纯的致密官能化的γ-内酰胺的合成。从对映体纯的2-氮杂环丁烷酮已经完成了完全手性转移。在-78°C的条件下,将乙炔锂添加到4-氧杂氮杂环丁烷-2-甲醛中,可顺利制得具有出色的非对映选择性的炔丙醇。炔丙醇转化为甲磺酸酯,其通过暴露于叠氮化钠得到相应的叠氮化物。β内酰胺轴承用三苯基膦(TPP)叠氮基侧链的处理,得到λ 5-未分离的-磷腈(亚氨基正膦,膦亚胺)。甲醇钠促进的磷腈β-内酰胺反应通过在四元内酰胺上发生N1-C2键断裂的过程平稳地提供了γ-内酰胺,同时伴随着环的膨胀,然后水解。