Palladium‐Catalyzed Coupling of N‐Amino­azoles with 3‐Halo‐Substituted ­Quinolin‐2(1H)‐ones, Coumarins, Quin­oxalin‐2(1H)‐ones, and Chromenes

Abstract

An efficient and general palladium‐catalyzed coupling of 3‐bromoquinolin‐2(1H)‐ones, 3‐bromocoumarins, 3‐chloroquinoxalin‐2(1H)‐ones, and 3‐iodo‐2H‐chromenes with a variety of 1‐aminoazoles is described. The reaction proceeds cleanly in the presence of the Pd(OAc)2/4,5‐bis(diphenylphosphino)‐9,9‐dimethylxanthene (Xantphos) catalytic system to provide the coupling products in good to excellent yields.

Design and Synthesis of 3‐(N‐Substituted)aminocoumarins as Anticancer Agents from 3‐Bromopeuruthenicin

“…We found that the reaction of 3‐bromocoumarin 2 with 3‐bromosubstituted aniline 5 f (2 eq) in the presence of Pd(OAc) 2 /( o ‐Tol) 3 P as the catalyst and Et 3 N as a base in DMF was characterized by the yield to 57%. Increasing of the yield of compound 8 f (to 88%) was observed by using of Pd(OAc) 2 ‐Xantphos‐Cs 2 CO 3 , a versatile and efficient catalytic system for the coupling of a wide range of nitrogen‐containing nucleophiles, including amides, sulfonamides, and functionalized alkylamines with 3‐halogen substituted coumarins …”

“…An alternate method was based on the condensation of salicylaldehydes with glycine derivatives . An efficient palladium‐catalyzed C−N bond coupling reaction between 3‐bromocoumarins and a variety of nitrogen containing nucleophiles (amides, sulfonamides, carbamates, amines, and ureas) or 1‐aminoazoles was described. Copper‐catalyzed in situ C ( sp 2 )‐NH 2 bond formation (coupling–reduction sequences) to provide 3‐aminocoumarins from 3‐bromocoumarins, has been achieved using sodium azide .…”