The presence of steric hindrance triggers different reaction pathways in the intramolecular oxidative aromatic coupling of tetraaryl-pyrrolo[3,2-b]pyrroles and leads to the formation of a fluorene moiety and a new cationic π-system linked together by a spiro carbon atom. Computational studies elegantly rationalized these results. These previously unknown functional dyes emit red light with reas...

Diastereoselective reactions between 4-formylpyrazoles, N-substituted maleimides and glycine derivates led to new series of pyrazolyldipyrrolo [3,4-a:3',4'-f]pyrrolizines and pyrazolylpyrrolo[3,4-c]pyrroles in good yields. The reactions proceeded by a domino process through azomethine ylides formed in situ via a 1,3-dipolar cycloaddition reaction.

The rhodium-catalyzed oxidative C2-olefination of indoles and pyrroles containing N-arylcarboxamide directing groups with a range of alkenes and subsequent cleavage of directing groups is described. This method provides direct and efficient access to C2-functionalized free (NH)-heterocycles.

The title compounds, (4-trifluoromethoxyphenyl)-2,5-dimethyl-3-(2-R-thiazol-4-yl)-1H-pyrroles, were prepared in four steps starting from commercially available 4-trifluoromethoxyaniline. The pyrrole (second ring) was added in one step using the Paal-Knorr method. The thiazole (third ring) was added in three steps using chloroacylation with chloroacetonitrile followed by heterocyclization with t...

A norbornene-mediated palladium-catalyzed sequence is described in which an alkyl-aryl bond and an aryl-heteroaryl bond are formed in one reaction vessel. The aryl-heteroaryl bond-forming step occurs via a direct arylation reaction. A number of six-, seven-, and eight-membered ring-annulated indoles, pyrroles, pyrazoles, and azaindoles were synthesized from the corresponding bromoalkyl azole an...

A cyclization reaction between enamides and alkynes catalyzed by palladium(II) acetate is described. In this method, the molecular oxygen serves as an efficient oxidant for the Pd(II)/Pd(0) catalytic cycle. The simple reaction conditions permit this methodology to be used as a general tool for the preparation of multi-substituted pyrroles.

Lewis acid-mediated conjugate addition of vinyl azides to electron-deficient alkenes led to the efficient construction of 1-pyrroline skeletons. The reactions of vinyl azides with 3-alkylidene-2-oxoindolines afford 3',4'-dihydrospiro[indoline-3,2'-pyrrol]-2-ones in a diastereoselective fashion, whereas those with dimethyl 2-alkylidenemalonates provide 4,5-dihydro-3H-pyrroles.

A highly efficient Cu-catalyzed ring expansion reaction of 2H-azirines with terminal alkynes has been developed. This transformation provides a powerful method for the synthesis of 3-alkynyl polysubstituted pyrroles under mild conditions in good yields. The direct transformation process, specific selectivity, and good tolerance to a variety of substituents make it an alternative approach to the...

A new reaction model, tandem Michael addition/formal isocyanide insertion into the acyl C-C bond, has been developed. Thus, a series of 2-acylpyrroles and seven-/eight-membered ring fused pyrroles were synthesized from the reaction of methyl isocyanides with enones in a single operation.