Regioselective Hydroacylation of 1,3-Dienes by Cobalt Catalysis
نویسندگان
چکیده
We describe a cobalt-catalyzed hydroacylation of 1,3-dienes with non-chelating aldehydes. Aromatic aldehydes provide 1,4-addition products as the major isomer, while aliphatic aldehydes favor 1,2-hydroacylation products. The kinetic profile supports an oxidative cyclization mechanism involving a cobaltacycle intermediate that undergoes transformation with high regio- and stereoselectivity.
منابع مشابه
ADDITION OF UNSYMMETRICAL DIENES TO ACYL-1,4-BENZOQUINONES AND OXIDATION OF THE ADDUCTS WITH MANGANESE DIOXIDE: A REGIOSPECIFIC ROUTE TO MONO- AND DI-METHYL-1,4-NAPHTHOQUINONES
Regioselective Diels-Alder reactions of acyl-1,4-benzoquinones 1 with, severally, isoprene, trans-piperylene,1-acetoxy-1,3-butadiene and 1-methoxy-1,3-butadiene gave the corresponding adducts 2 in high yield. Treatment of the adducts 2 with manganese dioxide gave regiospecifically the corresponding 1,4-naphthoquinones 3. In several cases, the adducts of the acetylquinones afforded intermediates...
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