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Title: N-Acylphthalimides: Efficient Acyl Coupling Reagents in Suzuki–Miyaura Cross-Coupling by N–C Cleavage Catalyzed by Pd–PEPPSI Precatalysts
We report a general, highly selective method for Suzuki–Miyaura cross-coupling of N-acylphthalimides via N–C(O) acyl cleavage catalyzed by Pd–PEPPSI-type precatalysts. Of broad synthetic interest, the method introduces N-acylphthalimides as new, bench-stable, highly reactive, twist-controlled, amide-based precursors to acyl-metal intermediates. The reaction delivers functionalized biaryl ketones by acylative Suzuki–Miyaura cross-coupling with readily available boronic acids. Studies demonstrate that cheap, easily prepared, and broadly applicable Pd–PEPPSI-type precatalysts supported by a sterically demanding IPr (1,3-Bis-(2,6-diisopropylphenyl)imidazol-2-ylidene) ancillary ligand provide high yields in this reaction. Preliminary selectivity studies and the effect of Pd–N-heterocyclic carbenes (NHC) complexes with allyl-type throw-away ligands are described. We expect that N-acylphthalimides will find significant use as amide-based acyl coupling reagents and cross-coupling precursors to acyl-metal intermediates.
Authors:
; ;
Award ID(s):
1650766
Publication Date:
NSF-PAR ID:
10090744
Journal Name:
Catalysts
Volume:
9
Issue:
2
Page Range or eLocation-ID:
129
ISSN:
2073-4344
Sponsoring Org:
National Science Foundation
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