42981-93-1Relevant articles and documents
Synthesis process 2 - methyl -3 - methoxybenzoic acid
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, (2021/10/20)
The invention discloses a synthesis process of 2 - methyl -3 - methoxybenzoic acid, which comprises the following steps: (1) reducing hydrogenation reaction: taking 2 - methyl -3 - nitrobenzoic acid or 2 - methyl -3 - nitrobenzoate as raw materials and methanol as a solvent. The hydrogen is a hydrogen source, and palladium carbon or platinum carbon is used as a catalyst to prepare 3 - amino -2 - methyl benzoic acid or 3 - amino -2 - methyl benzoic acid methyl ester by hydrogenation reduction. (2) Diazotization and hydrolysis and esterification one-pot reaction: preparing and hydroxyl 3 - methyl benzoic acid methyl ester by carrying out diazotization and hydrolysis -2 - esterification reaction under the action of a reducing product as a raw material and methanol as a solvent and a diazotization reagent. (3) Methylation reaction: methyl benzoate serving 3 - hydroxyl -2 - is used as a raw material, dimethyl sulfate is used as a methylation reagent, and methyl benzoate is produced 3 - methoxy -2 - methyl benzoate in the presence of a base. (4) Hydrolysis Reaction: methyl 3 - methoxy -2 - methyl benzoate and base. Water is mixed, heated and hydrolyzed, the reaction is complete, the product precipitated by acid conditioning PH through 1-3, filtered, and dried to obtain 3 - methoxy -2 -methylbenzoic acid.
NOVEL MACROCYCLIC DERIVATIVES, PROCESS FOR PREPARING SAME AND PHARMACEUTICAL COMPOSITIONS CONTAINING SAME
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Paragraph 0240; 0242, (2020/08/25)
Compound of formula (I): wherein A1, A2, Ra, Rb, Rc, Rd, R3, R4, X, Y and G are as defined in the description, and their use in the manufacture of medicaments.
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.
