An enantioselective Biginelli reaction has been developed by using a bifunctional primary amine-thioureaâTfOH (BPAT·TfOH) as a chiral phase-transfer catalyst and t-BuNH2·TFA as an additive in saturated brine at room temperature. The corresponding dihydropyrimidines were obtained in moderate-to-good yields with up to 99% ee under mild conditions. A plausible transition state has been proposed to explain the origin of the activation and the asymmetric induction.
在室温饱和盐
水中,使用双功能
伯胺-
硫脲-TfOH(
BPATÂ-TfOH)作为手性相转移催化剂和 t-BuNH2Â-TFA 作为添加剂,开发了一种对映体选择性 Biginelli 反应。在温和的条件下,得到了相应的二氢
嘧啶,收率从中等到良好,ee高达 99%。研究人员提出了一种可信的过渡态来解释活化和不对称诱导的起源。