TiCl2/nano-γ-Al2O3 as a new heterogeneous Lewis acid catalyst was synthesized and characterized by FE-SEM, XRD, FT-IR, EDS, XRF, BET and TGA. N-substituted pyrroles have been synthesized via Paal–Knorr reaction in the presence of TiCl2/nano-γ-Al2O3 at room temperature under solvent-free conditions.

One-step reactions between squaric acid and pyrroles, such as 3-ethyl-2,4-dimethyl-pyrrole 1,2,5-trimethylpyrrole, in water provide the corresponding pyrrol-2-yl- pyrrol-3-yl-containing semisquaraines high yields. These serve useful precursors for synthesis of various non-symmetric pyrrole-containing squaraine dyes.

Asymmetric coupling proceeds efficiently between propargylic acetates, cycloalkenes and electron-rich heteroarenes including indoles, pyrroles, activated furans thiophenes. 2,3-Disubstituted tetrahydrofurans pyrrolidines are produced in trans configuration excellent enantiomeric ratios. The reaction via Wacker-type attack of nucleophilic on alkenes by allenyl PdII species.

Herein, a synthesis of 2-phosphonodihydrofurans and 2-phosphonodihydropyrroles via 5-endo cyclization O-and N-propargylated compounds is described. The reaction promoted by potassium tert-butoxide allows fast access to interesting heterocycles which were easily converted into 2-arylated pyrroles under acidic conditions.

An unprecedented organocatalytic enantioselective formal synthesis of bromopyrrole alkaloid natural products is reported. An organocatalytic aza-Michael addition using pyrroles as the N-centered nucleophile is utilized as the enantioselective step to construct the nitrogen-substituted stereogenic carbon center in bromopyrrole alkaloids in good yield and excellent enantioselectivity. The aza-Mic...

The cationic ruthenium catalyst Ru(3)(CO)(12)/NH(4)PF(6) was found to be highly effective for the intermolecular coupling reaction of pyrroles and terminal alkynes to give gem-selective alpha-vinylpyrroles. The carbon isotope effect on the alpha-pyrrole carbon and the Hammett correlation from a series of para-substituted N-arylpyrroles (rho = -0.90) indicate a rate-limiting C-C bond formation s...

Herein, we report efficient visible light-induced photoredox reactions of C–H/N–H and C–X Bonds. These methods have provided access to varied portfolio synthetically important γ-ketoesters, azaspirocyclic cyclohexadienones spirocyclohexadienones, multisubstituted benzimidazole derivatives, substituted N,2-diarylacetamide, 2-arylpyridines 2-arylquinolines in good yields under mild conditions. Mo...

Acylethynylpyrroles, now readily available by the cross-coupling of pyrroles with acylbromoacetylenes in solid Al2O3 media, presence 1-methylimidazole underwent unprecedentedly easy (40–45 °C) cyclodimerization into bis(acylmethylidene)dipyrrolo[1,2-a:1′,2′-d]pyrazines up to 51% yield. Some other organic and inorganic basic catalysts can also trigger this cyclodimerization, but less efficiently.

An assisted tandem catalytic transformation of diallyl amines and diallyl ethers into N-aryl pyrroles and furans, respectively, is described. The sequence relies on ring closing metathesis followed by dehydrogenation of the initially formed dihydropyrroles and dihydrofurans. Both steps are Ru-catalyzed, but the sequence requires only one precatalyst, because conversion of the metathesis catalys...