A convenient method for the difluoromethylation of phenols and thiophenols, using diethyl bromodifluoromethylphosphonate (1) as a difluorocarbene precursor, is described. This commercially available phosphonate was found to undergo an extremely facile P–C bond cleavage on basic hydrolysis (−78 °C to rt), presumably leading to the bromodifluoromethyl anion, which subsequently converts to a difluorocarbene intermediate. The latter is trapped by phenolates 2 or thiophenolates 3 to give the corresponding difluoromethyl ethers and thioethers in good to excellent yield. The resulting eco-friendly side product, diethyl phosphate ion, is easily separated from the reaction mixture due to its excellent solubility in water. Due to the mild conditions applied to this reaction, phenolate ions bearing carbonyl or enolate functions are selectively difluoromethylated.

描述了使用溴代二氟甲基膦酸二乙酯（1）作为二氟卡宾前体的酚和硫酚的二氟甲基化的简便方法。人们发现，这种可商购的膦酸酯在碱性水解（-78°C至室温）下会经历极其容易的P–C键断裂，可能导致生成溴代二氟甲基阴离子，随后将其转化为二氟卡宾中间体。后者被酚盐2或硫酚盐3捕获以良好至优异的产率得到相应的二氟甲基醚和硫醚。所得的环保副产物磷酸二乙酯离子由于其在水中的优异溶解性而易于从反应混合物中分离出来。由于适用于该反应的温和条件，带有羰基或烯醇盐功能的酚盐离子被选择性地二氟甲基化。