Open Access Repository

Borane catalyzed selective diazo cross-coupling towards pyrazoles

Downloads

Downloads per month over past year

Dasgupta, A, Pahar, S, Babaahmadi, R, Gierlichs, L, Yates, BF ORCID: 0000-0001-9663-3301, Ariafard, A ORCID: 0000-0003-2383-6380 and Melen, RL 2022 , 'Borane catalyzed selective diazo cross-coupling towards pyrazoles' , Advanced Synthesis and Catalysis, vol. 364, no. 4 , pp. 773-780 , doi: 10.1002/adsc.202101312.

[img]
Preview
PDF (Published version)
150055 - Borane...pdf | 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
Authors/Creators:Dasgupta, A and Pahar, S and Babaahmadi, R and Gierlichs, L and Yates, BF and Ariafard, A and Melen, RL
Keywords: borane catalysis, DFT calculations, diazo compounds, diazoester, pyrazole, carbene, tris(pentafluorophenyl)borane, Density Functional Theory
Journal or Publication Title: Advanced Synthesis and Catalysis
Publisher: Wiley-V C H Verlag Gmbh
ISSN: 1615-4150
DOI / ID Number: 10.1002/adsc.202101312
Copyright Information:

2021 The Authors. Advanced Synthesis & Catalysis published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page
TOP