Site-Selective Double and Tetracyclization Routes to Fused Polyheterocyclic Structures by Pd-Catalyzed Carbonylation Reactions
作者:Francesco Pancrazzi、Nicolò Sarti、Paolo P. Mazzeo、Alessia Bacchi、Carla Carfagna、Raffaella Mancuso、Bartolo Gabriele、Mirco Costa、András Stirling、Nicola Della Ca’
DOI:10.1021/acs.orglett.0c00171
日期:2020.2.21
In this contribution, we report novel palladium-catalyzed carbonylative cascade approaches to highly functionalized polyheterocyclic structures. The Pd-catalyzed carbonylative process involves the regioselective insertion of one to three CO molecules and the sequential ordered formation of up to eight new bonds (one C-O, two C-C, five C-N). The exclusive formation of six-membered heterocycles is elucidated
Nitrogen heterocycles by palladium-catalysed oxidative cyclization-alkoxycarbonylation of acetylenic ureas
作者:Alessia Bacchi、Gian Paolo Chiusoli、Mirco Costa、Cristian Sani、Bartolo Gabriele、Giuseppe Salerno
DOI:10.1016/s0022-328x(97)00459-2
日期:1998.7
Acetylenic ureas readily undergo oxidative cyclization-alkoxycarbonylation reactions in the presence of PdI2 (or Pd/C)-KI as catalyst in methanol under mild conditions (65°C and 24 bar of a 3:1 mixture of CO and air). Cyclization occurs by trans-attack of oxygen or cis-attack of nitrogen functions on the triple bond, followed by stereospecific carbonylation, resulting in E or Z-stereochemistry, respectively