Merging α-Lithiation and Aldol-Tishchenko Reaction to Construct Polyols from Benzyl Ethers
作者:Carlos Sedano、Rocío Velasco、Samuel Suárez-Pantiga、Roberto Sanz
DOI:10.1021/acs.orglett.0c03014
日期:2020.10.16
α-Lithiobenzyl ethers, generated by selective α-lithiation, undergo an aldol-Tishchenko reaction upon treatment with carboxylic esters and paraformaldehyde. The reaction of the organolithium with the carboxylate generates an intermediate enolate that, after formaldehyde addition, affords 1,2,3-triol derivatives in a straightforward and one-pot manner. These products are obtained as single diastereoisomers
通过选择性α-锂化生成的α-亚硫基苄基醚经过羧酸酯和多聚甲醛处理后会发生aldol-Tishchenko反应。有机锂与羧酸盐的反应生成中间体烯醇盐,在添加甲醛后,该中间体烯醇化物以直接和一锅法的方式提供1,2,3-三醇衍生物。这些产物以带有四级立体中心的单一非对映异构体形式获得。Aldol-Tishchenko过程的完全非对映控制归因于过渡态下的立体电子偏好。