79383-44-1Relevant articles and documents
Preparation method of 2-methoxy-6-methylbenzoic acid
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Page/Page column 0020; 0026; 0030-0032; 0035-0037, (2021/07/08)
The invention discloses a synthesis process of 2-methoxy-6-methylbenzoic acid, which comprises the following steps: (1) reduction hydrogenation reaction: by taking 2-methyl-6-nitrobenzoic acid or methyl 2-methyl-6-nitrobenzoate as a raw material, methanol as a solvent, hydrogen as a hydrogen source and palladium on carbon or platinum on carbon as a catalyst, carrying out hydrogenation reduction to prepare 2-amino-6-methylbenzoic acid or methyl 2-amino-6-methylbenzoate; (2) diazotization, hydrolysis and esterification one-pot reaction: by taking the reduction product as a raw material, and methanol as a solvent, performing diazotization, hydrolysis and esterification reaction under the action of a diazotization reagent to prepare methyl 2-hydroxy-6-methylbenzoate; (3) methylation reaction: with methyl 2-hydroxy-6-methylbenzoate as a raw material and dimethyl sulfate as a methylation reagent, carrying out methylation reaction in the presence of alkali to prepare methyl 2-methoxy-6-methylbenzoate; and (4) hydrolysis reaction: mixing the methyl 2-methoxy-6-methylbenzoate with alkali and water, conducting heating for hydrolysis, conducting cooling after the reaction is completed, adjusting the pH value to 1-3 by using acid, separating out a product, and conducting filtering and drying to obtain the 2-methoxy-6-methylbenzoic acid.
Copper-Catalyzed One-Pot Synthesis of Dibenzofurans, Xanthenes, and Xanthones from Cyclic Diphenyl Iodoniums
Zhu, Daqian,Li, Min,Wu, Zhouming,Du, Yongliang,Luo, Bingling,Huang, Peng,Wen, Shijun
supporting information, p. 4566 - 4571 (2019/07/09)
Oxygenation of cyclic diphenyl iodoniums (CDPIs) with varied medium-ring sizes has been fully investigated. This practical copper-catalyzed tandem reaction of CDPIs with water as the oxygen source enables the construction of derivatised dibenzofurans and xanthenes at moderate to good yields. Moreover, structurally important xanthones are also successfully accessed under the oxygenation conditions with additional TEMPO.
Assessment of the regioselectivity in the condensation reaction of unsymmetrical o-phthaldialdehydes with alanine
D'Hollander, Agathe C.A.,Westwood, Nicholas J.
supporting information, p. 224 - 239 (2017/12/08)
One approach for the synthesis of isoindolinones, a privileged bioactive heterocyclic core structure, involves a condensation reaction of o-phthaldialdehydes with a suitable nitrogen-containing nucleophile. This fascinating reaction is revisited here in the context of the use of o-phthaldialdehydes that contain additional substituents in the aromatic ring leading to a detailed analysis of the regioselectivity of the reaction. Eleven monosubstituted o-phthaldialdehydes were synthesised and reacted with alanine. The regioselectivity observed across the eleven substrates led to the design of a disubstituted substrate that reacted with very high control. A gram-scale reaction followed by esterification gave one major regioisomer in high yield. In addition, the regioselectivity observed on reaction of two novel monodeuterated substrates led to an increased mechanistic understanding.