103681-96-5Relevant articles and documents
Sequential Directed Ortho Metalation-Boronic Acid Cross-Coupling Reactions. A General Regiospecific Route to Oxygenated Dibenzopyran-6-ones Related to Ellagic Acid
Alo, B. I.,Kandil, A.,Patil, P. A.,Sharp, M. J.,Siddiqui, M. A.,et al.
, p. 3763 - 3768 (1991)
A general regiospecific synthesis of dibenzopyran-6-one derivatives 1a,c and 8a-i related to ellagic acid is described (Scheme I, Table I).The sequence involves directed ortho metalation-boronation of benzamides 4 to give the arylboronic acids 5, which, upon palladium-catalyzed cross-coupling with alkoxybromobenzenes 6 leads to the biphenylamides 7.BBr3 demethylation followed by acid-catalyzed cyclization affords pyranone 8.In this manner, the naturally occurring dibenzopyranones 1a, autumnariol (1c), and the heterocyclic analogue 13 (Scheme III) were efficiently prepared.
SYNTHETIC CONNECTIONS TO THE AROMATIC DIRECTED METALATION REACTION. UNSYMMETRICAL BIARYLS BY PALLADIUM-CATALYZED CROSS COUPLING OF DIRECTED METALATION-DERIVED ARYLBORONIC ACIDS WITH ARYL HALIDES
Sharp, M.J.,Snieckus, V.
, p. 5997 - 6000 (2007/10/02)
The arylboronic acids 2 and 4 derived by directed ortho metalation of benzamides and carbamates, undergo an efficient palladium-catalyzed cross coupling reaction with a variety of aryl halides to yield unsymmetrical biaryls and heterobiaryls (Table).