γ‑Amino C(sp3)–H Functionalization of Aliphatic Amines through a Light-Driven Triple Catalysis

We report intra- and intermolecular γ-amino C(sp3)–H functionalization of aliphatic amines using a vinylsulfone-based HAT (hydrogen atom transfer) auxiliary and a triple catalysis, which is composed of photoredox, cobalt, and Brønsted acid catalysts under visible light irradiation. The process accomplishes four elementary steps: (i) electrophilic carbon-centered radical formation on the HAT auxiliary via MHAT (metal hydride hydrogen atom transfer) reaction, (ii) generation of a γ-amino carbon-centered radical through 1,6-HAT reaction, (iii) single-electron oxidation to carbocation equivalents, and (iv) nucleophilic substitution with internal or external nucleophiles. As a result, this γ-amino C(sp3)–H functionalization afforded γ-amino-functionalized products, such as azetidines, 1,3-diamine, and 1,3-aminoalcohol derivatives.本研究报道了以基于乙烯砜的氢原子转移（HAT, hydrogen atom transfer）助剂与由光氧化还原、钴及布朗斯特酸催化剂组成的三重催化体系，在可见光照射下实现脂肪族胺的分子内与分子间γ-位C(sp³)-H官能化反应。该过程包含四个基元步骤：(i) 通过金属氢化物氢原子转移（MHAT, metal hydride hydrogen atom transfer）反应，在HAT助剂上生成亲电性碳中心自由基；(ii) 通过1,6-氢原子转移反应生成γ-氨基碳中心自由基；(iii) 经单电子氧化得到碳正离子等价体；(iv) 与内源或外源亲核试剂发生亲核取代反应。最终，该γ-氨基C(sp³)-H官能化反应可得到γ-氨基官能化产物，例如氮杂环丁烷、1,3-二胺及1,3-氨基醇衍生物。