Vilsmeier reagent (DMF-POCl3) was used as an efficient formylating agent. Several sterols having sec-hydroxyl group at 3/17-position have been modified into respective formate esters. The method is simple, mild, chemoselective and provides sec-alcoholic protection in good yields. (c) 2006 Elsevier Inc. All rights reserved.
ortho-Formylation of estrogens. Synthesis of the anti-cancer agent 2-methoxyestradiol
作者:Øyvind W. Akselsen、Trond Vidar Hansen
DOI:10.1016/j.tet.2011.08.005
日期:2011.10
Several estrogens were mono-formylated using a mixture of paraformaldehyde. MgCl2, and Et3N in refluxing THF. In all cases, the 2-isomer was formed as the major product with high regioselectivity compared to the 4-isomer. Excellent to high yields were obtained in all examples except one. The method was applied for an efficient synthesis of the anti-cancer agent 2-methoxyestradiol. (C) 2011 Elsevier Ltd. All rights reserved.