33528-09-5Relevant articles and documents
Preparation method of 2-methoxy-6-methylbenzoic acid
-
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.
Pd(OAc)2-catalyzed orthogonal synthesis of 2-hydroxybenzoates and substituted cyclohexanones from acyclic unsaturated 1,3-carbonyl compounds
Miyagi, Toshinori,Okada, Sho,Tada, Naoya,Sugihara, Masahiro,Kagawa, Natsuko,Takabatake, Tetsuhiko,Toyota, Masahiro
supporting information, p. 1653 - 1657 (2019/05/29)
A Pd-catalyzed orthogonal synthesis of substituted 2-hydroxybenzoates and substituted cyclohexanones was developed for the first time. The substituted 2-hydroxybenzoates were obtained from acyclic unsaturated 1,3-carbonyl compounds using a combination of catalytic Pd(OAc)2 and Cu(OAc)2. On the other hand, the substituted cyclohexanones were produced from similar substrates via catalytic Pd(OAc)2 and hydrogen chloride. Each transformation was clean, easy to work up, provided the desired compounds in good purities, and did not require column chromatography purification.
The scent of bacteria: Headspace analysis for the discovery of natural products
Citron, Christian A.,Rabe, Patrick,Dickschat, Jeroen S.
, p. 1765 - 1776 (2013/01/15)
Volatile compounds released by 50 bacterial strains, 45 of them actinobacteria in addition to three chloroflexi and two myxobacteria, have been collected by use of a closed-loop stripping apparatus, and the obtained headspace extracts have been analyzed by GC-MS. Excluding terpenes that have recently been published elsewhere, 254 compounds from all kinds of compound classes have been identified. For unambiguous compound identification several reference compounds have been synthesized. Among the detected volatiles 12 new natural products have been found, in addition to mellein, which was released by Saccharopolyspora erythraea. The iterative PKS for this compound has recently been identified by in vitro experiments, but mellein production in S. erythraea has never been reported before. These examples demonstrate that headspace analysis is an important tool for the discovery of natural products that may be overlooked using conventional techniques. The method is also useful for feeding experiments with isotopically labeled precursors and was applied to investigate the biosynthesis of the unusual nitrogen compound 1-nitro-2-methylpropane, which arises from valine. Furthermore, several streptomycetes emitted compounds that were previously recognized as insect pheromones, thus questioning if bacterial symbionts are involved in insect communication.
