Pyrroline synthesis via visible‐light‐promoted hydroimination of unactivated alkenes with N,N′‐dimethylpropylene urea as H‐donor

• Main Authors: Cai, Sai-Hu, Wang, Ding-Xing, Ye, Lu, Liu, Ze-Yao, Feng, Chao, Loh, Teck-Peng
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2020
• Subjects: Science::Chemistry; N-heterocycles; Visible Light
• Online Access: https://hdl.handle.net/10356/139419
• Institution: Nanyang Technological University

Synthesis of 3,4-pyrroline derivatives via visible-light-induced hydro/oxyimination of unactivated olefins is reported. In the presence of the photoredox catalyst fac-Ir(ppy)3, the key iminyl radical intermediate can be readily generated from O-acyl oximes, and undergoes intramolecular cyclization and H-abstraction from solvent or is trapped by TEMPO to give the corresponding hydro/oxyimination product, respectively. Mechanistic investigations indicate that N,N′-dimethylpropylene urea (DMPU) works as both reducing agent for catalyst regeneration and H-donor for product formation in this process.