Nature has devised many different biosynthetic pathways towards pyrrole rings. Next to the well-studied aminolaevulinic acid based biosynthesis of the porphyrins, it was shown that in the prodigiosins (3) each of the pyrrole rings is build in a different way, starting from proline, serine, glycine and acetate. Proline is also the pyrrole precursor in streptopyrrole, however, the carbonyl group ...

The ionic liquid 1-butyl-3-methyl-imidazolium hydrogen sulfate, [bmim]HSO4, was used as a catalyst and reaction medium for the pyrrole synthesis, and a wide range of aliphatic, aromatic, heteroaromatic and carboxylic 1,4-diketones easily underwent condensations with aniline and ethylenediamine to form polysubstituted pyrroles. Sequential decarboxylation/Paal-Knorr pyrrole condensation was obser...

Other than triarylamines, which are protonated by strong acids both at their N-atom and aromatic rings, pyrrole its N-substituted derivatives were exclusively the carbon atoms of heteroaromatic rings. Whereas with trifluoromethane sulfonic acid (TFS) stable pyrrolium salts obtained, weaker trifluoroacetic (TFA) oligomers formed. E.g., from N-(tert-butyl)pyrrole a dimeric compound could be unamb...

Materials Propionic acid (>98%), 4-(methylthio)benzaldehyde (>99%), Methyl triflate (MeOTf), triflic acid (>98%) and manganese (II) chloride tetrahydrate (99.9%) were purchased from Wako pure chemical (Osaka, Japan). Pyrrole (>99%) was purchased from Tokyo chemical industry (Tokyo, Japan). Synthesis of

N-fused aza-indacene-based fluorophores 1 and 2 were prepared via a three-component condensation involving benzimidazole-carbinol, trifluoroacetic acid, and either pyrrole or indole, respectively. The N-fused aza-indacenes act as optical-based chemosensors for dissolved carbon dioxide gas following fluoride anion-mediated deprotonation.

A new conjugated polymer, PDTTTPD, comprising 2,5-di(thiophen-2-yl)thieno[3,2-b]thiophene and thieno[3,4-c]pyrrole-4,6-dione units, exhibits high crystallinity and excellent thermal stability. A device incorporating PDTTTPD and [6,6]-phenyl-C(71)-butyric acid methyl ester (1:1, w/w) exhibited a power conversion efficiency of 5.1%.

The asymmetric unit of the title compound, C(26)H(36)N(2)O(8), comprises two independent mol-ecules. In each mol-ecule, the two pyrrole rings are linked by a -CH(2)CH(2)- bridge, with dihedral angles between the two pyrrole rings of 14.5 (3) and 16.4 (3)° in the two mol-ecules. Each pyrrole ring carries 2- and 5-methyl substituents and eth-oxy-carbonyl groups at the 3- and 5-positions.