Organic amine-mediated free-radical carbocyclization reactions of 2,2,2-trihalogeno-substituted N-(2-alkynylphenyl)acetamides.

An efficient method for the synthesis of 3-halogeno-substituted 4-benzoylquinolin-2-(1H)-ones from N-(2-alkynylphenyl)-substituted trihaloacetamides has been developed, in which organic amines (TNPA and DIEA) act as the electron donors. In this carbocyclization reaction, a new C-C bond formation occurred regioselectively via a 6-exo-dig radical cyclization. A variety of useful functional groups are compatible with the reaction conditions.

Electrophilic carbocyclization reactions of 2-(2-alkynylphenyl)amino-1,4-naphthoquinones.

An efficient Ag(i)-catalyzed method for the synthesis of 5H-benzo[b]naphtho[2,3-f]azepine-6,11-diones from 2-(2-ethynylphenyl)amino substituted 1,4-naphthoquinones has been developed. In this transformation new C-C bond formation occurred regioselectively via a 7-endo-dig cyclization. The related 13-iodine substituted benzazepine derivatives could also be produced exclusively by the I2-induced carbocyclization reaction of 2-(2-alkynylphenyl)amino substituted 1,4-naphthoquinones.

Cobalt salt-catalyzed carbocyclization reactions of α-bromo-N-phenylacetamide derivatives.

An efficient and low-cost method for the synthesis of 4-substituted quinolin-2-(1H)-ones has been developed. In the presence of TBHP, the cobalt(ii)-catalyzed carbocyclization reactions of arylethenyl substituted α-bromo-N-phenylacetamides, involving sequential 6-exo-trig radical cyclization, t-butylperoxy radical cross-coupling reaction and the base-promoted ionic Kornblum-DeLaMare reaction, produced 4-benzoylquinolin-2-(1H)-ones. A variety of useful functional groups such as methoxy, fluoro, chloro, bromo, methoxycarbonyl, and cyano groups, are compatible with the reaction conditions.

Free radical reaction between 2-benzoyl-1,4-benzoquinones and 1,3-dicarbonyl compounds.

A manganese(III)-mediated reaction between 2-benzoyl-1,4-benzoquinones and 1,3-dicarbonyl compounds that produces benzo[c]furan-4,7-diones and anthracene-1,4-diones with high chemoselectivity is described. With ethyl butyrylacetate, by changing the solvent, benzo[c]furan-4,7-diones and anthracene-1,4-diones can be generated in high chemoselectivities. With ethyl benzoylacetate, N ,N-dimethyl acetoacetamide and 1,3-diones, benzo[c]furan-4,7-diones were produced effectively with high selectivity.

A novel manganese(III) acetate mediated reaction between 2-benzoyl-1,4-naphthoquinones and 1,3-dicarbonyl compounds.

A manganese(III)-mediated reaction between 2-benzoyl-1,4-naphthoquinones and 1,3-dicarbonyl compounds is described. This reaction provides an effective method for the synthesis of naphtho[2,3-c]furan-4,9-diones and naphthacene-5,12-diones, and it shows fair to high chemoselectivity depending on the electronic effect of the benzoyl group substituent on the reactants. With ethyl benzoylacetate and 1,3-diketones, the novel naphtho[2,3-c]furan-4,9-diones were produced effectively with high selectivity.