College of Pharmacy and Research Institute of Pharmaceutical Science and Technology (RIPST), Ajou University, Suwon 16499, Republic of Korea.
Org Lett. 2021 Feb 5;23(3):1135-1140. doi: 10.1021/acs.orglett.1c00154. Epub 2021 Jan 25.
A diastereoselective synthesis of -2-alkyl-6-aryl-3,6-dihydro-2-pyrans has been described. Dehydrogenative cycloetherification of ()-(±)-1-aryl-5-hydroxy-1-alkenes promoted by DDQ proceeded cleanly via 6- cyclization to afford -2-alkyl-6-aryl-3,6-dihydro-2-pyrans (32 examples) in good yield (up to 89%) and with moderate to excellent diastereoselectivity (up to 99:1). The synthetic utility of the method was illustrated by the second total synthesis of (±)-(2,6)-3,4-dehydro-1,7-bis(4-hydroxy phenyl)-4'-de--methyl centrolobine and a total synthesis of (±)-centrolobine.
已描述了（±）-1-芳基-5-羟基-1-烯烃的立体选择性合成-2-烷基-6-芳基-3,6-二氢-2-吡喃。DDQ 促进的（）-（±）-1-芳基-5-羟基-1-烯烃的脱氢环醚化反应通过 6-环化顺利进行，以高收率（高达 89%）和中等至优异的立体选择性（高达 99:1）得到-2-烷基-6-芳基-3,6-二氢-2-吡喃（32 个实例）。该方法的合成实用性通过（±）-（2,6）-3,4-去氢-1,7-双（4-羟基苯基）-4'-去--甲基中脑啡和（±）-中脑啡的全合成得到了说明。
