Carbon–carbon bond formation via thermal intermolecular hydrogen atom transfer: two serendipitous heterocyclic examples

Author(s):  
Richard J. Hamlyn ◽  
Richard H. Jones ◽  
Christopher A. Ramsden
2021 ◽  
Vol 2079 (1) ◽  
pp. 012020
Author(s):  
Zhiyu Feng

Abstract The alkenylation of cyclic ethers with β-nitroalkenes using uranyl cation as a photocatalyst is reported. Previous studies revealed the feasibility of incorporating organic photocatalyst in the visible light mediated alkenylation, while the uranyl cation serves as an alternative photocatalyst candidate successfully accomplish this transformation through a different pathway. The reaction features the direct hydrogen atom transfer (HAT) process to activate alpha C(sp3)-H of cyclic ether, and consequently cyclic ether is coupled with β-nitroalkene to give the target product with F-selectivity through C-C bond formation.


2012 ◽  
Vol 2012 (20) ◽  
pp. 3818-3829 ◽  
Author(s):  
Elisa I. León ◽  
Ángeles Martín ◽  
Inés Pérez-Martín ◽  
Luís M. Quintanal ◽  
Ernesto Suárez

2020 ◽  
Vol 18 (24) ◽  
pp. 4519-4532 ◽  
Author(s):  
Hui Chen ◽  
Shouyun Yu

Visible light photoredox catalysis combined with intramolecular hydrogen atom transfer (HAT) can serve as a unique tool for achieving remote C–C bond formation. Recent advances in photoredox-catalyzed remote C–C bond formation are summarized.


2019 ◽  
Author(s):  
Shiori Date ◽  
Kensei Hamasaki ◽  
Karen Sunagawa ◽  
Hiroki Koyama ◽  
Chikayoshi Sebe ◽  
...  

<div>We report here a catalytic, Markovnikov selective, and scalable synthetic method for the synthesis of saturated sulfur heterocycles, which are found in the structures of pharmaceuticals and natural products, in one step from an alkenyl thioester. Unlike a potentially labile alkenyl thiol, an alkenyl thioester is stable and easy to prepare. The powerful Co catalysis via a cobalt hydride hydrogen atom transfer and radical-polar crossover mechanism enabled simultaneous cyclization and deprotection. The substrate scope was expanded by the extensive optimization of the reaction conditions and tuning of the thioester unit.</div>


2020 ◽  
Author(s):  
Shunya Ohuchi ◽  
Hiroki Koyama ◽  
Hiroki Shigehisa

A catalytic synthesis of cyclic guanidines, which are found in many biologically active compounds and natu-ral products, was developed, wherein transition-metal hydrogen atom transfer and radical-polar crossover were employed. This mild and functional-group tolerant process enabled the cyclization of alkenyl guanidines bearing common protective groups, such as Cbz and Boc. This powerful method not only provided the common 5- and 6-membered rings but also an unusual 7-membered ring. The derivatization of the products afforded various heterocycles. We also investigated the se-lective cyclization of mono-protected or hetero-protected (TFA and Boc) alkenyl guanidines and their further derivatiza-tions.


Sign in / Sign up

Export Citation Format

Share Document