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Title: Protocol for Palladium/N-Heterocyclic Carbene-Catalyzed Suzuki–Miyaura Cross-Coupling of Amides by N–C(O) Activation
Abstract Amides are among the most important and ubiquitous functional groups in organic chemistry and process development. In this Practical Synthetic Procedure, a protocol for the Suzuki–Miyaura cross-coupling of amides by selective N–C(O) bond activation catalyzed by commercially available, air- and moisture-stable palladium/N-heterocyclic carbene (NHC) complexes is described. The procedure described involves [Pd(IPr)(cin)Cl] [IPr = 2,6-(diisopropylphenyl)imidazol-2-ylidene, cin = cinnamyl] at 0.10 mol% at room temperature and is performed on decagram scale. Furthermore, a procedure for the synthesis of amide starting materials is accomplished via selective N-tert-butoxycarbonylation, which is the preferred method over N-acylation. The present protocol carries advantages of operational simplicity, commercial availability of catalysts, and excellent conversions at low catalyst loadings. The method is generally useful for activation of N–C(O) amide bonds in a broad spectrum of amide precursors. The protocol should facilitate the implementation of amide cross-coupling reactions.
Authors:
; ; ; ; ;
Award ID(s):
1650766
Publication Date:
NSF-PAR ID:
10224911
Journal Name:
Synthesis
Volume:
53
Issue:
04
Page Range or eLocation-ID:
682 to 687
ISSN:
0039-7881
Sponsoring Org:
National Science Foundation
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