Yang Kin S, Rawal Viresh H
Department of Chemistry, The University of Chicago , Chicago, Illinois 60637, United States.
J Am Chem Soc. 2014 Nov 19;136(46):16148-51. doi: 10.1021/ja510135t. Epub 2014 Nov 7.
A general, asymmetric synthesis of amino acid derivatives is reported. Masked acyl cyanide (MAC) reagents are shown to be effective umpolung synthons for enantioselective additions to N-Boc-aldimines. The reactions are catalyzed by a modified cinchona alkaloid, which can function as a bifunctional, hydrogen bonding catalyst, and afford adducts in excellent yields (90-98%) and high enantioselectivities (up to 97.5:2.5 er). Unmasking the addition products gives acyl cyanide intermediates that are intercepted by a variety of nucleophiles to afford α-amino acid derivatives. Notably, the methodology provides an alternative method for peptide bond formation.
报道了一种通用的氨基酸衍生物不对称合成方法。掩蔽酰基氰（MAC）试剂被证明是用于对N - Boc - 醛亚胺进行对映选择性加成的有效极性翻转合成子。反应由一种修饰的金鸡纳生物碱催化，该生物碱可作为双功能氢键催化剂，加成产物收率优异（90 - 98%），对映选择性高（高达97.5:2.5的对映体比例）。脱除加成产物的保护基得到酰基氰中间体，该中间体可被多种亲核试剂捕获，从而得到α - 氨基酸衍生物。值得注意的是，该方法为肽键形成提供了一种替代方法。
