Work

Chemoselectivity for Alkene Cleavage by Palladium‐Catalyzed Intramolecular Diazo Group Transfer from Azide to Alkene

Year: 2018

Type: article

Abstract: ) variant is rare. Chemoselectivity for these azide to alkene diazo group transfers (DGT) is typically disfavored, thus limiting their synthetic utility. Herein, this work discloses a palladium-catalyzed intramolecular azide to alkene DGT, which grants chemoselectivity over competing aziridination. The data support a catalytic cycloreversion mechanism distinct from other known metal-catalyzed azide/alkene reactions: nitrenoid/metalloradical and (3+2) cycloadditions. Kinetics experiments reveal an unusual mechanistic profile in which the catalyst is not operative during the rate-controlling step, rather, it is active during the product-determining step. Catalytic DGT was used to synthesize N-heterocyclic quinazolinones, a medicinally relevant structural core. We also report on the competing aziridination and subsequent ring expansion to another N-heterocyclic core structure of interest, benzodiazepinones.

Source: Chemistry - A European Journal

DOI: 10.1002/chem.201805904

Authors: Grant B. Frost, Michaela N. Mittelstaedt, Christopher J. Douglas

Institution: University of Minnesota

Language: English

Topic: Cyclopropane Reaction Mechanisms

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: Curtin University of Technology, National Institutes of Health, National Institute of General Medical Sciences

Award: Alkaloid Synthesis via Asymmetric C-CN Activation