The reaction of 5,5-dimethyl-1,3-cyclohexanedione (dimedone) with various aromatic aldehydes catalyzed by tamarindwater produces 2,2ʹ-arylmethylenebis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives in 85-98% yield underwater bath heating at 60°C. Xanthene derivatives as cyclized products have not been obtained by this procedure.This method provides several advantages such as environmental friendliness, high yields and simple work-up procedure.The product is purified by simple filtration followed by crystallization with ethanol and drying processes.

中文翻译：

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罗望子水催化改进的2,2′-芳基亚甲基双（3-羟基-5,5-二甲基-2-环己烯-1-酮）衍生物的合成：一种绿色方法

罗望子水催化5,5-二甲基-1,3-环己二酮（二甲酮）与各种芳香醛的反应生成2,2′-芳基亚甲基双（3-羟基-5,5-二甲基-2-环己烯-1-一）衍生物以85-98％的产率在60°C下加热水下浴。该方法尚未获得作为环化产物的吨衍生物，该方法具有环境友好，收率高和后处理简单等优点，该产物可通过简单过滤，随后用乙醇结晶和干燥工艺进行纯化。