对我们最近报道的手性Pd(II)配合物催化的丙二酸酯与二氢异喹啉(DHIQs)的不对称加成反应进行了详细的机理研究。发现DHIQ与(Boc)2 O的反应原位生成了N,O-乙缩醛,作为酸碱催化剂的Pd(II)配合物的协同作用使得手性Pd烯醇盐形成和反应性亚胺离子通过α片段化 通过以DDQ作为氧化剂进行氧化也可以得到亚胺离子,并以四氢异喹啉(THIQs)为起始原料实现了催化不对称氧化曼尼希型反应。该氧化方案适用于N-丙烯酰基保护的THIQ,可通过分子内迈克尔反应有效合成光学活性的四氢苯并[ a ]喹啉二嗪衍生物。
Experimental and Computational Studies Unraveling the Peculiarity of Enolizable Oxoesters in the Organocatalyzed Mannich-Type Addition to Cyclic N-Acyl Iminium Ions
作者:Andrea Menichetti、Sebastiano Di Pietro、Valeria Di Bussolo、Lucilla Favero、Mauro Pineschi
DOI:10.3390/molecules25081903
日期:——
some organocatalyzed reactions proceeding with a high enantioselectivity. In our experimentation we found that the use of these compounds as the enolizable (nucleophilic) component in organocatalyzed Mannich-type reactions using in situ-generated cyclicN-acyliminiumions gave low diastereoselectivity and low to moderate values of enantioselectivity. This significant drop of facial selectivity with respect