2-Ethoxy-3-pyridylboronic acid: A versatile reagent for the synthesis of highly-functionalised 3-aryl/heteroaryl-pyridines via Suzuki cross-coupling reactions

Thompson, A.E.; Batsanov, A.S.; Bryce, M.R.; Saygili, N.; Parry, P.R.; Tarbit, B.

Abstract

This paper describes the commercially-viable synthesis and isolation of 2-ethoxy-3-pyridylboronic acid on a ca. 70 g scale via a directed ortho-metalation reaction on readily-available 2-ethoxypyridine. A range of efficient cross-coupling reactions of 2-ethoxy-3-pyridylboronic acid with selected aryl/heteroaryl halides under palladium-catalysed Suzuki-Miyaura conditions yield novel 2-ethoxy-3-aryl/heteroaryl-pyridines in high yield (heteroaryl=pyridyl, pyrimidyl, pyrazyl). The X-ray crystal structure of 2-ethoxy-3-pyridylboronic acid reveals that the boronic acid group takes part in an intramolecular O-(HO)-O-... bond with the adjacent ethoxy substituent, and an intermolecular O-(HN)-N-... bond. (c) 2005 Elsevier Ltd. All rights reserved.

Citation

Thompson, A., Batsanov, A., Bryce, M., Saygili, N., Parry, P., & Tarbit, B. (2005). 2-Ethoxy-3-pyridylboronic acid: A versatile reagent for the synthesis of highly-functionalised 3-aryl/heteroaryl-pyridines via Suzuki cross-coupling reactions. Tetrahedron, 61(21), 5131-5135

• Journal Article Type: Article
• Publication Date: 2005-05
• Journal: Tetrahedron
• Print ISSN: 0040-4020
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 61
• Issue: 21
• Pages: 5131-5135
• Public URL: https://durham-repository.worktribe.com/output/1600639