43008-66-8Relevant articles and documents
Acyl and Decarbonylative Suzuki Coupling of N-Acetyl Amides: Electronic Tuning of Twisted, Acyclic Amides in Catalytic Carbon-Nitrogen Bond Cleavage
Liu, Chengwei,Li, Guangchen,Shi, Shicheng,Meng, Guangrong,Lalancette, Roger,Szostak, Roman,Szostak, Michal
, p. 9131 - 9139 (2018)
We report the Pd-catalyzed acyl and the Ni-catalyzed biaryl Suzuki-Miyaura cross-coupling of N-acetyl-amides with arylboronic acids by selective N-C(O) cleavage. Activation of the amide bond by N-acylation provides electronically destabilized, acyclic, nonplanar amide, which readily undergoes cross-coupling with a wide range of boronic acids to produce biaryl ketones or biaryls in a highly efficient manner. Most crucially, the presented results introduce N-acetyl-amides as reactive acyclic amides in the emerging manifold of transition-metal-catalyzed amide cross-coupling. The scope and origin of high selectivity are discussed. Mechanistic studies point to remodeling of amidic resonance and amide bond twist as selectivity determining features in a unified strategy for cross-coupling of acyclic amides. Structural studies, mechanistic investigations as well as beneficial effects of the N-acyl substitution on cross-coupling of amides are reported.
Steric and Electronic Effects in the Synthesis and Regioselective Hydrolysis of Unsymmetrical Imides
Shang, Jing,Pourvali, Aysa,Cochrane, James R.,Hutton, Craig A.
, p. 1854 - 1858 (2015/12/26)
The AgI-promoted coupling reaction of thioamides and carboxylic acids is shown to be a useful method for the generation of unsymmetrical imides. The reaction proceeds efficiently with unhindered and electron-rich or neutral coupling partners, but not with hindered thioamides (such as thiopivalamides) or electron deficient thioamides (such as trifluorothioacetamides). Intriguingly, thioformamides are also ineffective coupling partners, despite having minimal steric or electronic influence. Hindered carboxylic acid coupling partners (such as pivalic acid) are tolerated, but electron deficient acids, such as trifluoroacetic acid, are ineffective coupling partners. Furthermore, an interplay of both steric and electronic effects is observed in the subsequent hydrolysis of unsymmetrical imides. Imides with a dimethoxybenzoyl group give high regioselectivity upon hydrolysis, favouring cleavage of the distal acyl group. Imides with a p-nitrobenzoyl or pivaloyl group give reversed selectivity, favouring cleavage of the proximal acyl group.
Acyclic ketene aminal phosphates derived from N,N-diprotected acetamides: stability and cross-couplings
Simas, Alessandro B.C.,de Sales, Daniel L.,Pais, Karla C.
experimental part, p. 6977 - 6980 (2010/02/27)
The synthesis of a stable ketene aminal phosphate (α-phosphoryloxy enecarbamate) derived from N,N-diprotected acetamide, bearing two different removable protecting groups, is disclosed. This synthetic intermediate underwent successful palladium-catalyzed cross-coupling reactions to afford functionalized enynes and dienes.