基于选择性羟基保护合成3-烷基-5,7-二羟基-6-氯-4-色满酮

Synthesis of 3-Alkyl-5,7-dihydroxy-6-chloro-4-chromanones Based on Selective Protection of the Hydroxyl Groups

以2,4,6-三羟基苯甲酸为起始原料,经氯代、脱羧、酰化得1-(3-氯-2,4,6-三羟基苯基)烷基酮,该中间体采用MOMCl进行选择性羟基保护,随后经环合、脱保护得到两个标题化合物,总收率分别为30.9%和32.2%。产物结构经1HNMR、ESI-MS进行确证。此合成方法具有原料廉价易得、操作简单、收率较高等特点,适合在多酚羟基存在的条件下利用选择性酚羟基保护策略区域选择性地合成目标产物。

1-（3-Chloro-2,4,6-trihydroxyphenyl） alkylketones were successively prepared by chlorination,decarboxylation and acylation using 2,4,6-trihydroxybenzoic acid as the starting material.Selective protection of the hydroxyl groups of the intermediates with MOMCl followed by cyclization and deprotection delivered two 3-alkyl-5,7-dihydroxy-6-chloro-4-chromanones with the total yield of 30.9% and 32.2%,respectively.The structures of the target products were confirmed by -1HNMR and ESI-MS.This protocol features cheap and available materials,simple operation and high yields,which is suitable for the synthesis of the target products regioselectively in the presence of multi-hydroxyl groups using the strategy of selective protection of the hydroxyl groups.