The Photoaddition of Pyrroles to Arylethenes and Arylethynes

Abstract

The photochemical reactions of styrene, (E)-stilbene, phenylethyne, and diphenylethyne with pyrrole and N-methylpyrrole have been investigated. The pyrroles quench the fluorescence of the phenylethenes and phenylethynes efficiently and broad structureless emissions attributed to exciplexes are observed from the N-methylpyrrole systems. Substituted pyrroles (1:l and 2:l adducts) are formed from irradiation of the phenylethenes with pyrrole, and 2-styrylpyrroles result from the phenylethynes. Styrene, but none of the other arenes, undergoes photoaddition to N-methylpyrrole in the presence of 10 % acetic acid.

The Gold‐Catalyzed Hydroarylation of Alkynes with Electron‐Rich Heteroarenes – A Kinetic Investigation and New Synthetic Possibilities

“…2‐(1‐Phenylvinyl)‐1 H ‐pyrrole (1a) : Phenylacetylene (21.5 μL, 196 μmol, 1 equiv. ), pyrrole (67.9 μL, 979 μmol, 5 equiv.)…”

Microwave-Accelerated Alkylation of Arenes/Heteroarenes with Benzylic Alcohols Using Antimony(III) Chloride as Catalyst: Synthesis of O-Heterocycles

“…In all the cases, alkylation went smoothly to furnish the expected product/s in high yields (Table 1, entries [14][15][16][17][18][19][20].…”

Synthesis ofC-vinylpyrroles

“…150 The photochemical reactions of pyrrole with phenyl-and diphenylacetylenes afforded 2-(1-phenylvinyl)-(347a) and 2-(1,2diphenylvinyl)pyrroles 347b (a mixture of the E and Z isomers in approximately equal amounts) in yields of only 7% and 9%, respectively. 151 The low yields of the adducts were accounted 151 for by photoinduced dimerisation of arylacetylenes and the instability of the adduct 347a in air.…”