88430-97-1Relevant articles and documents
Beyond directed ortho metalation: Ru-catalyzed CAr-O activation/cross-coupling reaction by amide chelation
Zhao, Yigang,Snieckus, Victor
, p. 11224 - 11227 (2014/09/29)
Disclosed is a new, catalytic, and general methodology for the chemical synthesis of biaryl, heterobiaryl, and polyaryl molecules by the cross-coupling of o-methoxybenzamides with aryl boroneopentylates. The reaction is based on the activation of the unreactive C-OMe bond by the proximate amide directing group using catalytic RuH2(CO)(PPh3)3 conditions. A one-step, base-free coupling process is thereby established that has the potential to supersede the useful two-step directed ortho metalation/cross- coupling reaction involving cryogenic temperature and strong base conditions. High regioselectivity, orthogonality with the Suzuki-Miyaura reaction, operational simplicity, minimum waste, and convenient scale-up make these reactions suitable for industrial applications.
Regioselectivity in the Reductive Cleavage of Pyrogallol Derivatives: Reductive Electrophilic Substitution of Acetals of 2,3-Dimethoxyphenol
Azzena, Ugo,Melloni, Giovanni,Pisano, Luisa
, p. 261 - 266 (2007/10/02)
Acetals of 2,3-dimethoxyphenol were used as the starting materials for the transformation of 1,2,3-trioxygenated benzenes into various 1-oxygenated-2,3-dicarbon-substituted benzenes, via regioselective reductive electrophilic substitution of the 2-methoxy
Directed Ortho Metalation of N,N-Diethylbenzamides. Silicon Protection of Ortho Sites and the o-Methyl Group
Mills, Robert J.,Taylor, Nicholas J.,Snieckus, Victor
, p. 4372 - 4385 (2007/10/02)
New general methodology of value in aromatic chemistry based on silicon protection of preferred ortho metalation sites in benzamides and o-methyl groups in o-toluamides (1, 2, Scheme I) is described.According to these methodologies, routes (Scheme II and V) to 1,2,5-, 1,2,4,5-, and 1,2,3-substituted aromatics with a variety of functionalities and oxidation states have been developed (Tables I and II).These tactics are used for the synthesis of difficult to access halo (10a-b, Scheme III) and methyl (21,25, Scheme VI) heterocycles.Ipso bromodesilylation reactions with bromine lead regiospecifically to o-bromobenzamides (12a,c, 14, Scheme IV).Walk-around-the-ring metalation processes provide highly substituted aromatics 27, 28, 29, and 30 (Scheme VII); the X-ray structure of the hexasubstituted derivative 30 shows a significant puckering of the aromatic ring.Cesium fluoride induced carbodesilylation of o-silylbenzamides with benzaldehyde affords, after TsOH cyclization, phthalides (31a-c, Scheme VIII) and constitutes a neutral alternative to the directed ortho metalation approach. α- and α,α-silylated o-toluamides are used in fluoride-mediated carbodesilylation (34a,d, Scheme IX) and desilylative Peterson olefination (35, Scheme X) procedures, respectively.The utility of α-silylated o-toluamide for the synthesis of a tetralin (38, Scheme XI) via an o-quinodimethane species is given.
