Metal-Catalyzed Synthesis and Transformations of β-Haloenol Esters

Victorio Cadierno

doi:10.3390/catal10040399

Abstract

In the last years there has been an increasing interest in the search for protocols to obtain β-haloenol esters in an efficient and selective manner as they are versatile building blocks in synthetic organic chemistry. In this article, metal-catalyzed transformations allowing the access to both acyclic and cyclic (i.e., haloenol lactones) β-haloenol esters are reviewed. Metal-catalyzed reactions in which these molecules participate as substrates are also discussed.

Highlights

With a couple of representative examples, i.e., the addition of acetic acid to 1‐(chloroethynyl)‐4‐methylbenzene and 1‐bromooct‐1‐yne, the authors demonstrated the applicability of this procedure for the synthesis of related (Z)‐β‐chloroenol and Making use of a catalytic system composed of the gold(I) complex [AuCl(PPh3)] and the chloride abstractor AgPF6, a broad scope procedure for the preparation of acyclic (Z)‐β‐iodoenol esters was recently developed by Cadierno and co‐workers (Scheme 12) [59,60,61]
As shown in Scheme 15, the treatment of the bromoenol acetate 27 with different alkyl, aryl- and alkenyl-boron reagents in the presence of catalytic amounts of [Pd(PPh3)4] and a base cleanly afforded the corresponding trisubstituted olefins, which were isolated in high yields (73–89%) and with complete retention of the stereochemistry of the starting C=C bond
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Summary

Introduction

With a couple of representative examples, i.e., the addition of acetic acid to 1‐(chloroethynyl)‐4‐methylbenzene and 1‐bromooct‐1‐yne, the authors demonstrated the applicability of this procedure for the synthesis of related (Z)‐β‐chloroenol and Making use of a catalytic system composed of the gold(I) complex [AuCl(PPh3)] and the chloride abstractor AgPF6, a broad scope procedure for the preparation of acyclic (Z)‐β‐iodoenol esters was recently developed by Cadierno and co‐workers (Scheme 12) [59,60,61].

Results

Conclusion