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One-step, atom economical procedure is described for the preparation of the tricyclic core of martinellic acid from 2-(cyanomethyl)-3-oxo-N-arylbutanamides. This new method has several advantages, including high yields, mild conditions, high regioselectivity and the readily available substrates from cheap starting materials.

The Lewis acid mediated highly selective reactions of [beta]-hydroxymethylcyclopropanyl-amides which formed [gamma]-iminolactones, dihydroquinolin-2-ones, and [gamma]-lactames are reported.

A highly selective, IBX-promoted reaction has been developed for the oxidative cleavage of inert C(aryl)-N bonds on secondary amides while leaving the C(carbonyl)-N bond unchanged. This metal-free reaction proceeds under mild conditions (HFIP/H2O, 25 °C), providing facile access to various useful primary amides, some of which would be otherwise unattainable using conventional aminolysis and hydrolysis approaches. [ABSTRACT FROM AUTHOR]

A useful transformation of nitriles to N-phenyl amides has been achieved through a novel intermolecular phenyl transfer reaction from phenyl hydrazides and N-addition to nitriles in the presence of PIFA under mild and solvent-free conditions. This cross-coupling reaction includes the oxidative cleavage of sp² C-N bonds of phenyl hydrazides to form a phenyl radical and the subsequent N-addition to cyanos to form new sp² C-N bonds and provides efficient access to various N-phenyl amides in moderate to good yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

An efficient and convenient iron-catalyzed protocol has been developed for the synthesis of substituted pyrrolo[1,2-a]quinoxalines from 1-(N-arylpyrrol-2-yl)ethanone O-acetyl oximes through N-O bond cleavage and intramolecular directed C-H arylation reactions in acetic acid. [ABSTRACT FROM AUTHOR]

An alternative route has been developed for the construction of multisubstituted pyrrole derivatives from readily available, doubly activated cyclopropanes and anilines using an iron-mediated oxidation domino reaction (i.e., sequential ring-opening, cyclization, and dehydrogenation reactions). This reaction uses readily available reactants and is tolerant of a broad range of substrates, with the desired products being formed in good to excellent yields [ABSTRACT FROM AUTHOR]

An efficient and Brønsted acid free one-pot protocol to directly generate structurally sophisticated α-formylpyrrole derivatives in moderate to good yields has been demonstrated, involving an iron-mediated domino oxidation/formylation reaction of readily available 2,3-dihydro-1H-pyrroles in dimethyl sulfoxide and air atmosphere, in which dimethyl sulfoxide acts as the formyl donor. A possible mechanism is presented. [ABSTRACT FROM AUTHOR]

A novel iron-catalyzed vinylogous aldol condensation of Biginelli products with aryl aldehydes has been developed for the syntheses of potential bioactive (E)-6-arylvinyl-dihydropyrimidin-2(1H)-ones. These materials are valuable synthetic precursors to drug-like pyrido[4,3-d]pyrimidine derivatives. The amide group at the 5-position of the dihydropyrimidin-2(1H)-ones played an important role in the vinylogous aldol condensation reaction. [ABSTRACT FROM AUTHOR]

Mediated by sodium persulfate (Na2S2O8), a series of polysubstituted 4-pyridones were synthesized via self-condensation of N-aryl acetoacetamides, during which a novel N to C 1,3-acyl migration should be involved. The structure of 4-pyridone was unequivocally confirmed by X-ray diffraction analysis. However, the self-condensation of N-benzyl acetoacetamides under the same condition gave polysubstituted 2-pyridones instead of 4-pyridones. [ABSTRACT FROM AUTHOR]

We report a new thiourea-Brønsted acid cooperative catalytic system for the enantioselective cyanosilylation of aldehydes with yields up to 90% and enantioselectivities up to 88%. The addition of an achiral acid was found to be crucial for high asymmetric induction. Mechanistic investigations using a combination of NMR, ESI-MS, and density functional theory computations (including solvent corrections) at the M06/6-31G(d,p) level of theory suggest that the key catalytic species results from the cooperative interaction of bifunctional thioureas and an achiral acid that form well-defined chiral hydrogen-bonding environments. [ABSTRACT FROM AUTHOR]