The title procedure is investigated for various educts bearing different ligands at the amide nitrogen.

An auxiliary-enabled and Pd(OAc)2-catalyzed direct arylation of C(sp(3))-H bonds of cyclopropanes and production of di- and trisubstituted cyclopropanecarboxamides having contiguous stereocenters are reported. The installation of aryl groups on cyclopropanecarboxamides led to the assembling of novel mono- and di- aryl-N-(quinolin-8-yl)cyclopropanecarboxamide scaffolds and mono- and di- aryl-N-(2-(methylthio)phenyl)cyclopropanecarboxamides. The stereochemistry of products was unequivocally assigned from the X-ray structures of key compounds.

An auxiliary-aided Pd-catalyzed highly diastereoselective double C-H activation and direct bis-arylation of methylene C(sp(3))-H bonds of cyclobutanecarboxamides and the syntheses of several novel trisubstituted cyclobutanecarboxamide scaffolds having an all-cis stereochemistry are reported. Extensive screening of various auxiliaries and reaction conditions was performed to firmly establish the optimized reaction conditions required for effecting the mono- or double C-H arylation of cyclobutanecarboxamides. The auxiliary-attached cyclobutanecarboxamides 15a, 15g, and 15h, prepared from the auxiliaries such as, 8-aminoquinoline, 2-(methylthio)aniline, and N',N'-dimethylethane-1,2-diamine were found to undergo an efficient direct bis-arylation. The Pd-catalyzed arylation reaction of N-(quinolin-8-yl)cyclobutanecarboxamide 15a with one equivalent or more of aryl iodides, afforded the corresponding bis-arylated cyclobutanecarboxamides 16a-y. Nevertheless, the Pd-catalyzed arylation of 15a with just 0.5 equiv of the aryl iodides 13a, 13b, 13e, and 13m, selectively gave the corresponding monoarylated cyclobutanecarboxamides 17a-17d. The Pd-catalyzed arylation of 15g or 15h with one equivalent or more of aryl iodides afforded the bis-arylated cyclobutanecarboxamides 19a-19c and 21a-21m, respectively. However, the Pd-catalyzed arylations of compounds 15g or 15h with just 0.5 equiv of aryl iodides were ineffective. The stereochemistry of compounds obtained in this work was unambiguously assigned from the X-ray structures of representative products.

The diastereoselective Pd(OAc)-catalyzed, bidentate ligand-directed sp C-H activation/arylation followed by ring opening of cyclopropanecarboxamides, which were assembled from cyclopropanecarbonyl chlorides and bidentate ligands (e.g., 8-aminoquinoline and 2-(methylthio)aniline), has been investigated. The treatment of various cyclopropanecarboxamides with excess amounts of aryl iodides in the presence of the Pd(OAc) catalyst, AgOAc and AcOH directly afforded the corresponding multiple β-C-H arylated open-chain carboxamides (anti β-acyloxy amides). This method has led to the construction of several anti β-acyloxy amides that possess vicinal stereocenters with a high degree of stereocontrol with the formation of a new C-O bond and three new C-C bonds. A plausible mechanism for the formation of multiple β-C-H arylated open-chain carboxamides from the Pd-catalyzed, bidentate ligand-directed β-C-H arylation and the ring opening of cyclopropanecarboxamides is proposed based on several control experiments. The observed diastereoselectivity and anti stereochemistry of the β-acyloxy amides were ascertained based on X-ray structural analysis of representative β-acyloxy amides.

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