Regioselective Synthesis of Natural and Unnatural (Z)-3-(1-Alkylidene)phthalides and 3-Substituted Isocoumarins Starting from Methyl 2-Hydroxybenzoates
作者:Fabio Bellina、Donatella Ciucci、Piergiorgio Vergamini、Renzo Rossi
DOI:10.1016/s0040-4020(00)00125-3
日期:2000.4
benzene ring, have been selectively and efficiently synthesized by a new protocol which involves: (i) the conversion of methyl 2-hydroxybenzoates into the corresponding nonaflates; (ii) Pd-catalyzed alkynylation reactions of these derivatives; (iii) the conversion of the so obtained methyl 2-(1-alkynyl)benzoates into the corresponding carboxylic acids followed by a transition metal-catalyzed heteroannulation
(Z)-3-(1-亚烷基)邻苯二甲酸酯和3-取代的异香豆素,包括在苯环上带有取代基的化合物,已通过一项涉及以下方面的新方案进行了选择性和有效的合成:(i)2-羟基苯甲酸甲酯的转化放入相应的非aflates中;(ii)这些衍生物的钯催化炔基化反应;(iii)将如此获得的2-(1-炔基)苯甲酸甲酯转化为相应的羧酸,然后进行过渡金属催化的杂环化反应。该程序已用于制备天然产物,例如千古油品B,千古油品C,3-丙基异香豆素和青蒿素,或千古油品E的MEM-醚。