A simple and practical method for large scale preparation of optically pure ethyl 2-amino-1-cyclohexanecarboxylate was developed via a reductive amination of 2-oxo-cyclohexanecarboxylate with a chiral α-methylbenzylamine. The major diastereomer was isolated in optically pure form by a simple and efficient crystallization as its HBr salt. The diastereoselectivity as well as the selectivity was also improved.

中文翻译：

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通过不对称还原胺化方法实际合成对映体纯的顺式-2-氨基-1-环己烷甲酸乙酯

通过用手性α-甲基苄胺还原胺化2-氧代-环己烷甲酸乙酯，开发了一种简单实用的大规模制备光学纯的2-氨基-1-环己烷甲酸乙酯的方法。通过简单和有效的结晶为其HBr盐，以光学纯净的形式分离出主要的非对映异构体。非对映选择性以及选择性也得到改善。