Palladium(II)-catalyzed Heck reaction of aryl halides and arylboronic acids with olefins under mild conditions

Tanveer Mahamadali Shaikh,Fung-E Hong

doi:10.3762/bjoc.9.180

Tanveer Mahamadali Shaikh, Fung-E Hong

Open Access

https://doi.org/10.3762/bjoc.9.180

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Abstract

A series of general and selective Pd(II)-catalyzed Heck reactions were investigated under mild reaction conditions. The first protocol has been developed employing an imidazole-based secondary phosphine oxide (SPO) ligated palladium complex (6) as a precatalyst. The catalytic coupling of aryl halides and olefins led to the formation of the corresponding coupled products in excellent yields. A variety of substrates, both electron-rich and electron-poor olefins, were converted smoothly to the targeted products in high yields. Compared with the existing approaches employing SPO–Pd complexes in a Heck reaction, the current strategy features mild reaction conditions and broad substrate scope. Furthermore, we described the coupling of arylboronic acids with olefins, which were catalyzed by Pd(OAc)2 and employed N-bromosuccinimide as an additive under ambient conditions. The resulted biaryls have been obtained in moderate to good yields.

Highlights

Substituted olefins are important structural motifs in natural products, pharmaceuticals, bioactive compounds and organic materials [1,2]
Heck reaction of aryl halides with olefins
Ackermann et al reported the synthesis of stable N-aryl-substituted pyrrole and indole-derived secondary phosphine oxide (SPO)-preligands, which were utilized in Kumada–Corriu cross-coupling reactions [57]

Summary

Introduction

Substituted olefins are important structural motifs in natural products, pharmaceuticals, bioactive compounds and organic materials [1,2]. The coupling was carried out by using 1 mol % loading of Pd-complex 6 as a precatalyst, with styrene (2a, 1 mmol), and bromobenzene (1a, 1 mmol) in DMSO (2 mL), and at Scheme 1: Heck reaction of olefins with aryl halides and arylboronic acids. When K2CO3 (1.0 equiv) in THF was employed under similar reaction conditions, the yield of trans-stilbene was improved to 46% (Table 1, entry 8).

Results

Conclusion