Enantiospecific Stereodivergent Synthesis of<i>trans</i>- and<i>cis</i>-<i>N</i>(2),3-Dimethyl-4-phenyl-1,2,3,4-tetrahydroisoquinolines
作者:Steven J. Coote、Stephen G. Davies、Ai M. Fletcher、Paul M. Roberts、James E. Thomson
DOI:10.1002/asia.200900470
日期:2010.3.1
pseudoephedrine or ephedrine) give the corresponding trans‐N(2),3‐dimethyl‐4‐phenyl‐1,2,3,4‐tetrahydroisoquinolines with high levels of diastereoselectivity and in good yields of isolated product. The cyclizations of the corresponding chromium tricarbonyl complexes are rendered completely stereoselective. Acid‐promoted cyclization of N‐(3′,4′‐dimethoxybenzyl)ephedrine and its chromium tricarbonyl complex occur
的范围内的酸促进环化Ñ -benzylethanolamines得到相应的(从伪麻黄碱或导出的)反式- Ñ(2),3-二甲基-4-苯基-1,2,3,4-四氢异喹啉具有高水平的非对映选择性和分离产物的良好收率。使相应的三羰基铬络合物的环化完全立体选择性。的酸促进环化ñ - (3',4'-二甲氧基苄基)麻黄碱及其铬三羰基复合物与互补的非对映选择性发生,得到的反式-和顺式- Ñ(2),3-二甲基-4-苯基-6,7-二甲氧基-1,2,3,4-四氢异喹啉,分别在> 99:1博士中,后者与``双重反转''机理相一致,这涉及到三羰基铬部分的邻近基团参与,然后进行重新麦芽糖化反应,得到相应的顺式-四氢异喹啉,并保留了整体构型。