1758-25-4Relevant articles and documents
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 preparation method comprises the following steps: A, reacting 1,4-dimethoxybenzene with formaldehyde under the action of hydrogen halide to obtain 2-halomethyl-1,4-dimethoxybenzene; B, reacting 2-halomethyl-1,4-dimethoxybenzene obtained inthe step A with a cyanation reagent, then diluting, washing, drying and concentrating under reduced pressure, and finally carrying out reduced pressure distillation to obtain 2(2,5-dimethoxyphenyl)acetonitrile; and C, hydrolyzing the 2(2,5-dimethoxyphenyl)acetonitrile obtained in the step B, cooling, extracting, merging, drying, concentrating under reduced pressure and purifying to finally obtainthe 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, and the yield and the total yield of the 2,5-dimethoxyphenylacetic acid are higher than those of 2,5-dimethoxyphenylacetic acid synthesized by the Willgerodt-Kindler method.
Preparation method of 2,5-dimethoxyphenylacetic acid
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Paragraph 0024; 0029; 0032; 0037; 0040; 0045; 0047; 0052, (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.