A simple and scalable method for the preparation of N-Cbz protected amino acids is presented which uses a mixture of aqueous sodium carbonate and sodium bicarbonate to maintain the appropriate pH during the addition of benzyl chloroformate. The method has been extended to other N-protections and is amenable to large scale preparation of an intermediate toward Zofenopril, an ACE inhibitor.

中文翻译：

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一种改进的大规模制备N -Cbz氨基酸的方法

提出了一种简单且可扩展的制备N- Cbz保护的氨基酸的方法，该方法使用碳酸钠水溶液和碳酸氢钠的混合物在添加氯甲酸苄酯期间维持适当的pH。该方法已经扩展到其他N-保护，并且适合大规模制备ACE抑制剂佐芬普利的中间体。