3-Chloro-3-methoxy-pentane 、
(3S)-2,5-Dimethoxy-3-(3,4-dimethoxybenzyl)-3-methyl-3,6-dihydropyrazine 在
正丁基锂 作用下,
生成 (2S,5S)-2-(3,4-Dimethoxy-benzyl)-5-(1-ethyl-1-methoxy-propyl)-3,6-dimethoxy-2-methyl-2,5-dihydro-pyrazine 、
(2S,5R)-2-(3,4-Dimethoxy-benzyl)-5-(1-ethyl-1-methoxy-propyl)-3,6-dimethoxy-2-methyl-2,5-dihydro-pyrazine