Borane catalyzed selective diazo cross-coupling towards pyrazoles

Dasgupta, Ayan, Pahar, Sanjukta, Babaahmadi, Rasool, Gierlichs, Lukas, Yates, Brian F., Ariafard, Alireza and Melen, Rebecca L. ORCID: https://orcid.org/0000-0003-3142-2831 2022. Borane catalyzed selective diazo cross-coupling towards pyrazoles. Advanced Synthesis & Catalysis 364 (4) , pp. 773-780. 10.1002/adsc.202101312

Preview

PDF - Published Version Available under License Creative Commons Attribution. Download (4MB) | Preview

Abstract

Decomposition of donor-acceptor diazo compounds leads to the formation of reactive carbene intermediates. These can undergo a wide variety of carbene transfer reactions to yield synthetically useful products. Herein, we report a selective borane catalyzed cyclization reaction from the combination of two different diazo compounds to afford N-substituted pyrazoles. The selective decomposition of the more reactive α-aryl α-diazoester and subsequent reaction with a vinyl diazoacetate produces N-alkylated pyrazoles in a regioselective manner. Catalytic amounts of tris(pentafluorophenyl)borane (10 mol%) were employed to afford the pyrazole products (36 examples) in yields from 59 to 80%. Extensive DFT studies have been undertaken to interpret the mechanism for this reaction which was found to go through two tandem catalytic cycles, both catalyzed by B(C6F5)3.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Chemistry Cardiff Catalysis Institute (CCI)
Additional Information:	This is an open access article under the terms of the Creative Commons Attribution License
Publisher:	Wiley
ISSN:	1615-4150
Funders:	EPSRC
Date of First Compliant Deposit:	10 December 2021
Date of Acceptance:	25 November 2021
Last Modified:	24 May 2023 07:04
URI:	https://orca.cardiff.ac.uk/id/eprint/146076

Citation Data

Cited 4 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item