Katritzky Alan R, He Hai-Ying, Wang Jing
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
J Org Chem. 2002 Jul 12;67(14):4951-6. doi: 10.1021/jo010842w.
The reactions of (2S)-2-amino-2-substituted-N-(4-nitrophenyl)acetamides 16a-c, succindialdehyde (13), and benzotriazole afforded enantiopure (3S,5R,7aR)-5-(1H-1,2,3-benzotriazol-1-yl)-3-substituted-1-(4-nitrophenyl)tetrahydro-1H-pyrrolo[1,2-a]imidazol-2-ones 17a-c, which were converted by sodium borohydride into (3S,7aR)-3-substituted-1-(4-nitrophenyl)tetrahydro-1H-pyrrolo[1,2-a]imidazol-2-ones 18a-c. Chiral (2S)-2-amino-2-substituted-N-(4-methylphenyl)acetamides 12a-d, easily prepared in two steps from N-Boc-alpha-amino acids 10a-d, similarly reacted with glutaraldehyde (20) and benzotriazole to generate 5-benzotriazolyl-3-substituted-hexahydroimidazo[1,2-a]pyridin-2(3H)-ones 21a-d, which were converted by sodium borohydride directly into optically active 3-substituted-hexahydroimidazo[1,2-a]pyridin-2(3H)-ones 22a-d.
(2S)-2-氨基-2-取代基-N-(4-硝基苯基)乙酰胺16a - c、丁二醛(13)和苯并三唑反应，得到对映体纯的(3S,5R,7aR)-5-(1H-1,2,3-苯并三唑-1-基)-3-取代基-1-(4-硝基苯基)四氢-1H-吡咯并[1,2-a]咪唑-2-酮17a - c，其经硼氢化钠转化为(3S,7aR)-3-取代基-1-(4-硝基苯基)四氢-1H-吡咯并[1,2-a]咪唑-2-酮18a - c。手性(2S)-2-氨基-2-取代基-N-(4-甲基苯基)乙酰胺12a - d由N-Boc-α-氨基酸10a - d经两步轻松制备，其与戊二醛(20)和苯并三唑类似地反应，生成5-苯并三唑基-3-取代基-六氢咪唑并[1,2-a]吡啶-2(3H)-酮21a - d，其经硼氢化钠直接转化为光学活性的3-取代基-六氢咪唑并[1,2-a]吡啶-2(3H)-酮22a - d。
