Synthesis of meso-tetraphenyl porphyrins via condensation of dipyrromethanes with N-tosyl imines
摘要:
A new synthetic route for the synthesis of 5,10,15,20-tetraphenyl porphyrins has been developed based on the reaction of 5-substituted dipyrromethanes with N-tosyl imines in the presence of a metal triflate catalyst. meso-Substituted tetraphenyl porphyrins were synthesized in a two-step process. The first step of the method is the metal triflate-catalyzed condensation of 5-substituted dipyrromethanes with N-tosyl imines to form a porphyrinogen intermediate and the second step is the oxidation of the porphyrinogen to porphyrin. The method was applied to the synthesis of trans-A(2)B(2)-tetraarylporphyrins and the products were obtained with only a trace amount of one scrambling product. The synthesis of two important building blocks for porphyrin synthesis, mono and di-sulfonamide alkylated 5-substituted dipyrromethanes, was achieved by the addition of 5-substituted dipyrromethane to N-tosyl imine. The application of mono and di-sulfonamide alkylated 5-substituted dipyrromethanes in '2+2' porphyrin formation reactions is presented. (C) 2009 Elsevier Ltd. All rights reserved.
开发了一种新的、催化的和通用的方法,用于通过二吡咯甲磺酰胺与吡咯的反应直接合成不对称的 AB 型三吡喃。关键结构二吡咯甲磺酰胺是通过向 Cu(OTf)2 活化的甲苯磺酰亚胺中添加内消旋取代的二吡咯甲烷来合成的。引入的方法能够通过调整加成反应的条件以高产率选择性地制备四吡喃。2,3-二氯-5,6-二氰基-1,4-苯醌氧化四吡喃仅提供相应的A3-和反式-A2B-corroles。