AbstractA palladium‐catalyzed intramolecular CH bond sulfuration reaction of aryl thiocarbamates has been developed. This strategy provides a new route to benzo[d][1,3]oxathiol‐2‐ones with tolerance of a wide range of substituents. Mechanistic studies suggested that the CH activation–sulfuration to afford 2‐imino‐1,3‐benzoxathiole intermediate might involve an electrophilic palladation process.magnified image
A convenient and selective synthesis of alkynylated coumarins from various aryl thiocarbamates and 1,3‐diynes or terminal alkynes via rhodium‐catalyzed C−H bond activation has been developed. In this transformation, both symmetrical and asymmetrical 1,3‐diynes could be applicable, obtaining various 3‐alkynylated coumarins in moderate to excellent yields. When the substituent is aryl group, the resulting
Access to Coumarins by Rhodium-Catalyzed Oxidative Annulation of Aryl Thiocarbamates with Internal Alkynes
作者:Yingwei Zhao、Feng Han、Lei Yang、Chungu Xia
DOI:10.1021/acs.orglett.5b00364
日期:2015.3.20
A Rh-catalyzed annulation of aryl thiocarbamates with internal alkynes via C–H bond activation has been developed. This protocol provides a new route to 3,4-disubstituted coumarins.