The first base-mediated intermolecular cyclization of arylaldehydes and terminal arylacetylenes for the synthesis of a wide range of pyrroles in a single step has been described. The developed methodology used commercially available starting materials and tolerated a broad range of functional groups affording 2,3,5-triaryl-substituted-1H-pyrroles with good yields (up to 92% yield) under mild conditions
“One pot” regiospecific synthesis of polysubstituted pyrroles from benzylamines and ynones under metal free conditions
作者:Jinhai Shen、Guolin Cheng、Xiuling Cui
DOI:10.1039/c3cc43844a
日期:——
A convenient âone-potâ weak base-promoted synthesis of polysubstituted pyrroles has been developed from benzylamines and ynones. This transformation involves the Michael addition reaction and intramolecular condensation, which features high regioselectivity, high efficiency, environmental friendliness and metal free. A series of polysubstituted pyrroles were provided in up to 91% yield for 27 examples.
Synthesis of 2,2,5-Trisubstituted 2<i>H</i>-Pyrroles and 2,3,5-Trisubstituted 1<i>H</i>-Pyrroles by Ligand-Controlled Site-Selective Dearomative C2-Arylation and Direct C3-Arylation
作者:Miyuki Yamaguchi、Sakiko Fujiwara、Kei Manabe
DOI:10.1021/acs.orglett.9b02559
日期:2019.9.6
Palladium-catalyzed site-selectivedearomativeC2-arylation of 2,5-diaryl-1H-pyrroles with aryl chlorides was accomplished, and a series of 2,2,5-triaryl-2H-pyrroles were synthesized. In addition, the site selectivity of the reaction was switched by simply changing the ligand, and the direct C3-arylated 2,3,5-triaryl-1H-pyrroles were prepared. The obtained 2,2,5-triaryl-2H-pyrroles could be further
Visible Light‐Induced, Metal‐Free Denitrative [3+2] Cycloaddition for Trisubstituted Pyrrole Synthesis
作者:Bhupal S. Karki、Lalita Devi、Ayushi Pokhriyal、Ruchir Kant、Namrata Rastogi
DOI:10.1002/asia.201901068
日期:2019.12.13
A metal-free, regioselectivesynthesis of trisubstituted pyrroles has been developed through a formal [3+2] cycloaddition reaction between 2H-azirines and nitroalkenes under visible light/photoredox-catalyzed conditions. The reaction proceeds through 2H-azaallenyl radical addition on β-nitrostyrenes in a Michael fashion followed by a base-mediated denitration reaction. The directive group influence