Trifunctionalization of Cinnamyl Alcohols Provides Access to Brominated α,α-Difluoro-γ-lactones via a Photoinduced Radical–Polar–Radical Mechanism
作者:Roshan K. Dhungana、Albert Granados、Vittorio Ciccone、Robert T. Martin、Jadab Majhi、Mohammed Sharique、Osvaldo Gutierrez、Gary A. Molander
DOI:10.1021/acscatal.2c05514
日期:2022.12.16
A photochemical synthesis of brominated α,α-difluoro-γ-lactones from cinnamyl alcohols and ethyl bromodifluoroacetate is reported via one-pot Giese addition/lactonization/halogen-atom transfer (XAT) processes. This transformation provides brominated α,α-difluoro-γ-lactones in moderate to good diastereoselectivities. The reaction affords a rapid increase in molecular complexity in organofluorine chemical
通过一锅吉斯加成/内酯化/卤素原子转移 (XAT) 过程,报道了从肉桂醇和溴二氟乙酸乙酯光化学合成溴化 α,α-二氟-γ-内酯。这种转化提供了具有中等至良好非对映选择性的溴化 α,α-二氟-γ-内酯。该反应使有机氟化学空间的分子复杂性迅速增加。色散校正密度泛函理论 (DFT) 计算和实验支持内酯化诱导的自由基链机制,其中长寿命的自由基中间体经历非对映选择性卤素原子转移以重新启动自由基链循环。