Quantum Dot‐Catalyzed Photoreductive Removal of Sulfonyl‐Based Protecting Groups
Abstract
This Communication describes the use of CuInS2/ZnS quantum dots (QDs) as photocatalysts for the reductive deprotection of aryl sulfonyl‐protected phenols. For a series of aryl sulfonates with electron‐withdrawing substituents, the rate of deprotection for the corresponding phenyl aryl sulfonates increases with decreasing electrochemical potential for the two electron transfers within the catalytic cycle. The rate of deprotection for a substrate that contains a carboxylic acid, a known QD‐binding group, is accelerated by more than a factor of ten from that expected from the electrochemical potential for the transformation, a result that suggests that formation of metastable electron donor–acceptor complexes provides a significant kinetic advantage. This deprotection method does not perturb the common NHBoc or toluenesulfonyl protecting groups and, as demonstrated with an estrone substrate, does not perturb proximate ketones, which are generally vulnerable to many chemical reduction methods used for this class of reactions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 03, 2020
- Source ID
- 10.1002/anie.202005074
Entities
People
- Cameron R. Rogers
- Emily A. Weiss
- Kaitlyn A Perez
Organizations
- National Institutes of Health
- National Science Foundation
- National Science Foundation Directorate for Mathematical & Physical Sciences
- Northwestern University
- United States Department of Defense