Conjugate Addition of Lithium <i>N</i>-Phenyl-<i>N</i>-(α-methylbenzyl)amide: Application to the Asymmetric Synthesis of (<i>R</i>)-(−)-Angustureine
作者:Scott A. Bentley、Stephen G. Davies、James A. Lee、Paul M. Roberts、James E. Thomson
DOI:10.1021/ol200625h
日期:2011.5.20
The conjugate addition of lithium (R)-N-phenyl-N-(α-methylbenzyl)amide to a range of α,β-unsaturated 4-methoxyphenyl esters proceeds with excellent levels of diastereoselectivity to give the corresponding β-amino esters in good yield and as single diastereoisomers (>99:1 dr). The synthetic utility of this methodology has been demonstrated via the short and concise asymmetric synthesis of the tetrahydroquinoline
将锂(R)-N-苯基-N-(α-甲基苄基)酰胺共轭加成到一系列α,β-不饱和的4-甲氧基苯基酯中,其非对映选择性极好,从而得到良好的相应β-氨基酯收率和单一非对映异构体形式(> 99:1 dr)。该方法的合成效用已通过简短,简洁的不对称合成四氢喹啉生物碱(R)-(-)-牛尿素分六个步骤得到了证明,其总产率为32%(可从市售的oct-2-enoic酸制得)。