Palladium-catalyzed α,β-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand

TETRAHEDRON

卷:75

Article

Fulton, Tyler J.¹  Wu, Brenda¹  Alexy, Eric J.¹  Zhang, Haiming²  Stoltz, Brian M.¹ 

[1] CALTECH, Warren & Katharine Schlinger Lab Chem & Chem Engn, Div Chem & Chem Engn, 1200 E Calif Blvd, Pasadena, CA 91125 USA

[2] Genentech Inc, Small Mol Proc Chem, 1 DNA Way, San Francisco, CA 94080 USA

关键词: Dehydrogenation;    Palladium;    PHOX ligand;   

DOI  :  10.1016/j.tet.2019.05.065

来源: Elsevier

【 摘 要 】

A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted N-acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the Z-enol carbonate to provide dehydrogenation products exclusively in high E/Z selectivity, while the E-enol carbonate provides the alpha-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of Z-enol carbonates derived from N-acyl indoles to furnish acyclic formal alpha,beta-unsaturated ester equivalents. (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

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