Palladium-Catalyzed Heteroarylamination of Ethyl 2-Chloro-1-azaazulene-3-carboxylate and Annulation of Heteroarylamino-1-azaazurenes
摘要:
The palladium catalyzed heteroarylamination of ethyl 2-chloro-1-azaazulene-3-carboxylate was achieved using a catalyst based on Pd-2(dba)(3) / Xantphos system. Treatment of ethyl 2-(heteroarylamino)-1-azaazulene-3-carboxylates with a PPA-POCl3 mixture gave corresponding annulation products. 2-(2-Benzothiazolylamino)-1-azaazulene (3h) showed anticancer activity against HeLa S3 cells (IC50: 6.5 mu M).
Palladium-catalyzed amination of 2-chloro-1-azaazulene with 2-aminopyridine was studied under various conditions in order to obtain N-(1-azaazulen-2-yl)-N-(2-pyridyl)amine (4) and N,N-bis(1-azaazillen-2-yl)-N-(2-pyridyl)amine (5) as a multidentate ligand. Results of the reaction and physical and chemical properties of 4 and 5 are described.