Open AccessModifying Positional Selectivity in C–H Functionalization Reactions with Nitrogen-Centered Radicals: Generalizable Approaches to 1,6-Hydrogen-Atom Transfer Processes
Author(s) -
Melanie A. Short,
J. Miles Blackburn,
Jennifer L. Roizen
Publication year - 2019
Publication title -
synlett
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.712
H-Index - 133
eISSN - 1437-2096
pISSN - 0936-5214
DOI - 10.1055/s-0039-1691501
Subject(s) - chemistry , surface modification , selectivity , radical , amine gas treating , hydrogen atom , nitrogen atom , combinatorial chemistry , nitrogen , photochemistry , stereochemistry , organic chemistry , catalysis , ring (chemistry) , group (periodic table)
Nitrogen-centered radicals are powerful reaction intermediates owing in part to their ability to guide position-selective C(sp 3 )-H functionalization reactions. Typically, these reactive species dictate the site of functionalization by preferentially engaging in 1,5-hydrogen-atom transfer (1,5-HAT) processes. Broadly relevant approaches to alter the site-selectivity of HAT pathways would be valuable because they could be paired with a variety of tactics to install diverse functional groups. Yet, until recently, there have been no generalizable strategies to modify the position-selectivity observed in these HAT processes. This Synpacts article reviews transformations in which nitrogen-centered radicals preferentially react through 1,6-HAT pathways. Specific attention will be focused on strategies that employ alcohol- and amine-anchored sulfamate esters and sulfamides as templates to achieve otherwise rare γ-selective functionalization reactions.