AbstractReported herein is an unprecedented protocol for C(sp3)‐phosphinylation. With 1 mol % 4CzIPN (1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene) as the catalyst, the visible light induced reaction of redox‐active esters of aliphatic carboxylic acids with dimethyl arylphosphonites or diethyl alkylphosphonites at room temperature provides the corresponding decarboxylative phosphinylation products in satisfactory yields. The protocol exhibits broad substrate scope and wide functional‐group compatibility, enabling the late‐stage modification of complex molecules and rapid synthesis of bioactive phosphinic acids such as glutamine synthetase phosphinothricin and a kynureninase inhibitor. A radical‐polar crossover mechanism involving the formation and subsequent oxidation of phosphoranyl radicals followed by nucleophilic demethylation (or deethylation) is proposed.
摘要 本文报告了一种前所未有的 C(sp3)-膦酰化协议。以 1 mol % 4CzIPN (1,2,3,5-四(咔唑-9-基)-4,6-二氰基苯)为催化剂,在室温下,脂肪族羧酸的氧化还原活性酯与二甲基芳基亚膦酸盐或二乙基烷基亚膦酸盐在可见光的诱导下发生反应,以令人满意的收率得到相应的脱羧膦化产物。该方案具有广泛的底物范围和宽泛的官能团兼容性,能够对复杂分子进行后期修饰,并快速合成具有生物活性的膦酸,如谷氨酰胺合成酶phosphinothricin 和一种犬尿素酶抑制剂。提出了一种自由基-极性交叉机制,其中涉及磷酰自由基的形成和随后的氧化,然后是亲核去甲基化(或脱乙基化)。