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苯甲酰甲酯在有机合成中有广泛应用。Hendrickson等报道应用苯甲酰甲基作为酸和酚羟基的保护基团,它在许多条件下很稳定,但又可在较温和的条件下除去。苯甲酰甲酯的经典合成方法是利用羧酸盐与α-溴代苯乙酮反应制得,但此法存在着反应时间长、烃化试剂被水解、产率低、产品不纯等缺点。1974年Durstr报道以冠醚作相转移催化剂的苯甲酰甲酯的合成方法,可获得较好结果,但冠醚有较难制备、价格昂贵、毒性大的缺点。新近报道聚乙二醇可以折迭成螺旋结构(Ⅰ),因此具有类似冠醚的性质,可与金属正离子络合,此络合正离子可与负离子形成离子对而进入有机相中,起到相转移催化作用。
Phenacyl esters are widely used in organic synthesis. Hendrickson et al. Report the use of phenacyl as a protecting group for acid and phenolic hydroxyl groups, which is stable under many conditions but can be removed under milder conditions. The classic method for the synthesis of phenacyl esters is the use of carboxylic acid salt and α-bromo-acetophenone reaction, but this method has a long reaction time, hydrolysis of alkylating agents, low yield, impure products shortcomings . Durstr reported in 1974 the crown ether as a phase transfer catalyst for the synthesis of phenacylphenols can get better results, but the crown ether is more difficult to prepare, expensive, shortcomings of great toxicity. It has recently been reported that polyethylene glycol can be folded into a helical structure (I), which has crown ether-like properties and can complex with metal cations. The complexing cations can form ion pairs with the negative ions and enter the organic phase. To phase transfer catalysis.