(S)-3-(Boc-氨基)-2-哌啶酮 、
(2-溴乙氧基)-特丁基二甲基硅烷 在
(S)-tert-butyl 1-(2-(tert-butyldimethylsilyloxy)ethyl)-2-oxopiperidin-3-ylcarbamate 、 crude product 、 ethyl acetate hexanes 作用下,
以to provide compound (2d) in 26% yield的产率得到(S)-tert-butyl 1-(2-(tert-butyldimethylsilyloxy)ethyl)-2-oxopiperidin-3-ylcarbamate