(E)-1,8-二甲氧基-3-(3-氧代丁烯-1-基)-蒽-9,10-二酮的合成

Synthesis of(E)-1,8-dimethoxy-3-(3-oxobut-1-enyl)anthracene-9,10-dione

以芦荟大黄素为原料,首先利用硫酸二甲酯对芦荟大黄素分子中的酚羟基进行选择性甲基化反应,合成1,8-二甲基氧芦荟大黄素,然后用氯铬酸吡啶盐（PCC）氧化甲基化的芦荟大黄素合成出1,8-二甲基氧芦荟大黄醛,最后使用丙酮和1,8-二甲基氧芦荟大黄醛进行Aldol缩合反应,合成了标题化合物,并用元素分析、质谱和1HNMR对所合成化合物的结构进行了表征。结果表明,使用丙酮作为溶剂,K2CO3为催化剂,在60~70℃下搅拌反应6~12 h,可以选择性、高产率得到1,8-二甲基氧芦荟大黄素。对于丙酮和1,8-二甲基氧芦荟大黄醛的Aldol缩合,超声波具有较好的促进效果。

1,8-Dimethoxy aloe-emodin was synthesized from aloe-emodin using dimethyl sulfate for selective methylation of phenolic hydroxyl groups on the aloe-emodin molecule.Furthermore,aloe-emodin aldehyde was synthesized from 1,8-dimethoxy aloe-emodin using pyridinium chlorochromate（PCC） as the oxidant.Finally,（E）-1,8-dimethoxy-3-（3-oxobut-1-enyl）anthracene-9,10-dione was synthesized by the Aldol condensation reaction of acetone and aloe-emodin aldehyde in the NaOH medium,and the synthesized compounds were characterized by elementary analysis,ESI-MS and 1HNMR.The results indicated that 1,8-dimethoxy aloe-emodin could be obtained in high yields and good selectivity at 60～70 ℃upon stirring for 6～12 h in the acetone solvent using K2CO3 as the catalyst.The Aldol condensation reaction of acetone and aloe-emodin aldehyde could be promoted under ultrasonic irradiation.