1758-25-4Relevant articles and documents
Preparation method of 2, 5-dimethoxyphenylacetic acid
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, (2021/01/29)
The invention belongs to the technical field of drug synthesis, and particularly relates to a preparation method of 2, 5-dimethoxyphenylacetic acid, which comprises the following steps: A. Reacting 1,4-dimethoxybenzene with formaldehyde under the action of hydrogen halide, extracting by the reaction system, merging with organic phases, drying, concentrating under reduced pressure, and purifying the crude product to obtain 2-halon methyl-1, 4-dimethoxybenzene ; and B, under the protection of inert gas, putting the 2-halo methyl-1, 4-dimethoxybenzene obtained in the step A, magnesium or butyl lithium and carbon dioxide into a solvent, and then carrying out extraction and deactivation, reduced pressure distillation, extraction, organic phase combination and reduced pressure concentration toobtain the 2, 5-dimethoxyphenylacetic acid. The yield and the total yield of the 2, 5-dimethoxyphenylacetic acid obtained by the method disclosed by the invention are both higher than those of the 2,5-dimethoxyphenylacetic acid synthesized by a Willgerodt-Kindler method.
Preparation method of 2,5-dimethoxyphenylacetic acid
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, (2021/02/06)
The invention belongs to the technical field of drug synthesis, and particularly relates to a preparation method of 2,5-dimethoxyphenylacetic acid, wherein the method comprises the following steps: A,reacting 1,4-dimethoxybenzene in a formylation system to obtain 2,5-dimethoxybenzaldehyde; B, reacting the 2,5-dimethoxybenzaldehyde obtained in the step A with a reducing agent, extracting a reaction system, then combining organic phases, drying, concentrating under reduced pressure and distilling a crude product to obtain 2,5-dimethoxybenzyl alcohol; C, reacting the 2,5-dimethoxybenzyl alcoholobtained in the step B with a bromination reagent to obtain 2-bromomethyl-1,4-dimethoxybenzene; and D, reacting the 2-bromomethyl-1,4-dimethoxybenzene obtained in the step C with magnesium or butyl lithium and carbon dioxide in a solvent to obtain the 2,5-dimethoxyphenylacetic acid. The yield and the total yield of the 2,5-dimethoxyphenylacetic acid obtained by the method disclosed by the invention are both higher than those of 2,5-dimethoxyphenylacetic acid synthesized by a Willegerdt-Kindler method.
Syntheses of Covalently-Linked Porphyrin-Quinone Complexes (1)
Kong, Josephine L. Y.,Loach, Paul A.
, p. 737 - 744 (2007/10/02)
A synthetic route for the preparation of covalently-linked porphyrin-quinone and metalloporphyrin-quinone complexes as models for the phototrap in bacterial photosynthesis is described. 5-(4-Carboxyphenyl)-10,15,20-tritolylporphyrin, prepared by a mixed aldehyde approach, was attached to a benzoquinone center with a propanediol bridge by means of ester linkages.The starting point for the benzoquinone moiety was 2,5-dihydroxyphenylacetic acid, whose hydroquinone function was first protected by preparing its dimethylether.The spacing between the two centers of the complex could be altered simply by varying the length of the bridging group (a diol) employed.Boron tribromide was used to unmask the quinol derivatives in the final coupled products.The zinc(II) derivative of porphyrin quinone comple was prepared ba addition of a saturated solution of zinc acetate in methanol to a solution of the corresponding porphyrin-hydroquinone complex in dichloromethane at room temperature.The structures of these complexes were confirmed by nmr spectroscopy, uv-visible absorption, and mass spectroscopy.Oxidation of the quinol moiety in the covalently-linked complex to its corresponding quinonoid derivative was accomplished by treating a solution of the complex in dichloromethane with a stoichiometric amount of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, a high potential benzoquinone.