摘要
Abstract
3,5-Dihydroxy-4’-methoxystilbene (1.3), a key intermediate for the synthesis of resveratrol, was synthesized by an improved process. When the molar ratio of triphenyl (3,5-diacetoxybenzyl) phosphonium bromide (1) to CH3ONa is 1:1, 1 reacts with 4-methoxy benzaldehyde in DMF with CH3ONa as the base to afford three products, i.e., 3,5-diacetoxy-4’-methoxystilbene (1.1), 3-acetoxy-5-hydroxy-4’- methoxystilbene (1.2) and 3,5-dihydroxy-4’-methoxystilbene (1.3), respectively. While the molar ratio of 1 to CH3ONa is between 1:2 and 1:3, the major product is only 1.3. The same reaction between triphenyl (3,5-dihydroxybenzyl) phosphonium bromide (2) and 4-methoxy benzaldehyde in DMF can occur in the presence of CH3ONa as well. When the molar ratio of 2 to CH3ONa is 1:1, the major product is 1.3. If the molar ratio of 1 to CH3ONa is over 1:5, then no such coupling product was generated. Thus, resveratrol could be obtained by removing methyl groups in 1.3, comparing with other synthetic processes of resveratrol, which omittes the reaction step of eliminating acetyl group.关键词
3,5-二乙酰氧基苄基三苯基膦溴化盐/茴香醛/3,5-二羟基苄基三苯基膦溴化盐/Wittig反应Key words
triphenyl (3,5-diacetoxybenzyl) phosphonium bromide/4-methoxy benzaldehyde/triphenyl (3,5-dihydroxybenzyl) phosphonium bromide/Wittig reaction分类
化学化工
