The Ru(cod)(cot)-Catalyzed Alkenylation of Aromatic C−H Bonds with Alkenyl Acetates
journal contributionposted on 15.08.2007, 00:00 by Yusuke Matsuura, Masaru Tamura, Takuya Kochi, Mitsuo Sato, Naoto Chatani, Fumitoshi Kakiuchi
The regioselective Ru(cod)(cot)-catalyzed alkenylation of arylpyridines and related compounds with alkenyl acetates to give good-to-excellent yields of ortho-alkenylation products was developed. Several arylpyridines having electron-donating (CH3 and OCH3) and -withdrawing (CF3, CN, and Ac) groups and azoles, such as oxazoline, tetrazole, and thiazole, can be used in this coupling reaction. A variety of alkenyl acetates, such as 1-propenyl, 1-butenyl, 1-hexenyl, styryl, 2-methyl-1-propenyl, and 1-cyclohexenyl acetates, reacted with arylpyridines to give the corresponding ortho-alkenylation products in high yields. This direct alkenylation of aromatic C−H bonds with alkenyl acetates provides π-conjugated aromatic and heteroaromatic compounds under halogen-free reaction conditions.