72755-09-0Relevant articles and documents
O-Methylarenehydroxamates as Ortho-Lithiation Directing Groups. Ti(III)-Mediated Conversion of O-Methyl Hydroxamates to Primary Amides
Fisher, Lawrence E.,Caroon, Joan M.,Jahangir,Stabler, S. Russell,Lundberg, Scott,Muchowski, Joseph M.
, p. 3643 - 3647 (1993)
Reaction of O-methyl benzohydroxamates 2a-c with sec-butyllithium in the presence of TMEDA at -40 deg C regiospecifically generates the highly reactive N,ortho-dilithiated species (e.g. 3).These dilithio species react avidly with a wide spectrum of electrophilic reagents, including alkyl halides, givind adducts which on reduction with TiCl3 are converted into ortho-substituted primary benzamides in excellent yields.Ortho lithiation of O-methyl benzohydroxamates is thus formally equivalent to ortho lithiation of primary benzamides themselves.The utility of these synthetic operations is enhanced by the well-known facility with wich the primary amide moiety can be transformed into other useful functional groups.The conversion of O-methyl hydroxamates to primary amides is shown to be general, as exemplified by transformation of 14a-f to 15a-f.O-Methyl-2-methylbenzohydroxamate (4a) undergoes regiospecific dilithiation on nitrogen and on the methyl group when treated with sec-butyllithium at -70 deg C.These dilithio species react with DMF or "Weinreb-type" amides to give condensation products wich cyclize to N-methoxyisoquinolin-1(2H)-ones under mildly acidic conditions.Removal of the N-methoxy moiety under conditions analogous to those used for O-methyl benzohydroxamate provides N-unsubstituted isoquinolin-1(2H)-ones with high overall efficiency.This process is exemplified by the synthesis of isoquinolin-1(2H)-one 9a, its 3-n-butyl congener 9b, and the tricyclic isoquinolin-1(2H)-ones 20a and 20b from O-methyl 2-methylbenzohydroxamate (4a).
Palladium-Catalyzed Inert C?H Bond Activation and Cyclocarbonylation of Isoquinolones with Carbon Dioxide Leading to Isoindolo[2,1-b]isoquinoline-5,7-Diones
Yan, Kelu,Jin, Junbin,Kong, Yong,Li, Bin,Wang, Baiquan
supporting information, p. 3080 - 3085 (2019/05/21)
A palladium-catalyzed inert C?H bond activation and cyclocarbonylation of isoquinolones leading to isoindolo[2,1-b]isoquinoline-5,7-diones under 1 atm of carbon dioxide has been developed. This transformation features high regio- and chemo-selectivity, step-economy, and good functional group tolerance. Most of the corresponding products were obtained in moderate to good yields. It offers an alternative approach for the synthesis of useful diverse isoindolo[2,1-b]isoquinoline-5,7-dione derivatives. (Figure presented.).
Rhodium(III)-catalyzed chemodivergent annulations between: N-methoxybenzamides and sulfoxonium ylides via C-H activation
Xu, Youwei,Zheng, Guangfan,Yang, Xifa,Li, Xingwei
supporting information, p. 670 - 673 (2018/01/28)
Chemodivergent and redox-neutral annulations between N-methoxybenzamides and sulfoxonium ylides have been realized via Rh(iii)-catalyzed C-H activation. The sulfoxonium ylide acts as a carbene precursor, and coupling occurs under acid-controlled condition
