Enantioselective α-Benzylation of Aldehydes via Photoredox Organocatalysis
作者:Hui-Wen Shih、Mark N. Vander Wal、Rebecca L. Grange、David W. C. MacMillan
DOI:10.1021/ja106593m
日期:2010.10.6
The first enantioselective aldehydeα-benzylation using electron-deficient aryl and heteroaryl substrates has been accomplished. The productive merger of a chiral imidazolidinone organocatalyst and a commercially available iridium photoredox catalyst in the presence of household fluorescent light directly affords the desired homobenzylic stereogenicity in good to excellent yield and enantioselectivity
asymmetric alkylation of aldehydes was studied, by using a homemade, custom-designed photoreactor for reactions under cryogenic conditions. Going from microfluidic conditions up to a 10 mL mesofluidic reactor, an increase of productivity by almost 18000 % compared to the batch reaction was demonstrated. Finally, for the first time, a stereoselective photoredox organocatalytic continuous flow reaction
通过使用自制、定制设计的光反应器在低温条件下进行反应,研究了醛的连续流动、对映选择性、有机光氧化还原催化不对称烷基化。从微流控条件到 10 mL 中流控反应器,与分批反应相比,生产率提高了近 18000%。最后,首次成功实现了在完全伸缩过程中用于活性药物成分 (API) 合成的立体选择性光氧化还原有机催化连续流动反应。最终工艺由四个操作单元组成:连续流动下可见光驱动的不对称催化苄基化、在线连续后处理、中和和最终的氧化酰胺化步骤,得到 95% ee 的药物活性分子