Application of β-Oxodithioesters in Domino and Multicomponent Reactions: Facile Route to Dihydropyrimidines and Coumarins
作者:Okram Mukherjee Singh、Nepram Sushuma Devi
DOI:10.1021/jo802585b
日期:2009.4.17
A facile route to hitherto unknown 5-methylmercaptothio-carbonyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones and substituted 2H-chromene-2-thiones has been developed. SnCl2 catalyzed cyclocondensation of beta-oxodithioesters with a variety of readily accessible aldehydes and urea affords the dihydropyrimidinones. The methodology involves the three-component Biginelli reaction. On the other hand, substituted salicylaldehyde and beta-oxodithioesters reacted under the same condition to afford the substituted 2H-chromene-2-thiones in high yields.
Silica-ZnCl<sub>2</sub>: An Efficient and Reusable Solid Catalyst for One Pot Synthesis of 5-Methyl Mercaptothiocarbonyl-4-aryl-3-dihydropyrimidin-2(1<i>H</i>)-ones Under Solvent-Free Conditions
作者:Laishram Ronibala Devi、Leimajam Vartima Chanu、Hojune Choi、Dahyun Lee、Okram Mukherjee Singh、Sang-Gyeong Lee
DOI:10.1002/bkcs.10606
日期:2015.12
Synthetic application of Silica–ZnCl2 , as an efficient and eco‐friendly catalyst for the synthesis of a small library of dihydropyrimidinones is described in this report. The reaction involves a onepot, multicomponent reaction of β‐oxodithiocarboxylates, aldehydes, and urea under solvent‐free conditions. The experimental procedure is simple, environmental benign, tolerated with many functional groups