The first examples of a Pd-catalyzed carbonylation of aryl boronic acids with sp3 carbon partners are presented. Various boronic acids were shown to react with 1,3-diesters and 1,3-diketones to afford structurally unique carbonyl compounds. By employing 2-substituted 1,3-diesters, synthetically-challenging quaternary carbon centres were accessed. In total, 42 examples of aryl carbonyl compounds were prepared in moderate to good yields. The catalytic system features the use of a bidentated phosphine ligand and a relatively low CO pressure (5 atm), providing an easy, alternative method for the preparation of triketones.
Synthesis of novel 5-alkyl/aryl/heteroaryl substituted diethyl 3,4-dihydro-2<i>H</i>-pyrrole-4,4-dicarboxylates by aziridine ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters
作者:Satish S More、T Krishna Mohan、Y Sateesh Kumar、U K Syam Kumar、Navin B Patel
DOI:10.3762/bjoc.7.95
日期:——
A novel synthetic methodology has been developed for the synthesis of diethyl 5-alkyl/aryl/heteroaryl substituted 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates (also called 2-substituted pyrroline-4,5-dihydro-3,3-dicarboxylic acid diethyl esters) by iodide ion induced ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters in very good to excellent yields under