8 results about "Methyl methoxyacetate" patented technology

The present application discloses a method for preparing methyl ester compounds, which comprises subjecting a raw material of a carboxyl compound, methanol and / or dimethyl ether to an esterification reaction to obtain a methyl ester compound; wherein the general formula I of the carboxyl compound is R-CH2-COOH, and R is a methoxy group or a hydroxyl group; and the methyl ester compound comprises at least one of methyl methoxyacetate and methyl glycolate. The present application also discloses a method for preparing methyl glycolate, comprising the steps of: a) subjecting methylal to a carbonylation reaction with carbon monoxide to obtain methyl methoxyacetate; b) subjecting methyl methoxyacetate to a hydrolysis reaction with water to obtain methyl glycolate; and c) subjecting glycolic acid and methoxyacetic acid to an esterification reaction with methanol and dimethyl ether to obtain methyl glycolate. The above method can greatly simplify the separation process, save energy consumption, and provide a new synthetic route for the synthesis of methyl ester compounds, especially methyl glycolate.

The application discloses a method for modifying hydrogen type Y molecular sieve by ammonium fluoride and application of the hydrogen type Y molecular sieve in preparation of methyl methoxyacetate, and belongs to the field of catalytic chemistry. The modification method comprises the following steps: S1, hydrogen type Y molecular sieve is added into an ammonium fluoride aqueous solution, stirring reaction is carried out, filtration is carried out, and washing is carried out; S2, the filtered and washed molecular sieve is subjected to ammonium exchange; and S3, the ammonium exchanged molecular sieve is subjected to drying and calcination, so that the hydrogen type Y molecular sieve modified by the ammonium fluoride is obtained. The ammonium fluoride modified Y molecular sieve can fully open the six-membered ring window between SOD cages and supercages, is beneficial to exerting the carbonylation performance of the high-activity Bronsted acid in the SOD cage, and thus the selectivity and synthesis efficiency of the methyl methoxyacetate are improved. The method for modifying the Y molecular sieve by the ammonium fluoride can be rapidly realized at low temperature, and the carbonylation performance of the conventional Y or USY molecular sieve is significantly improved; the silicon-aluminum ratio changes little before and after treatment, and the product yield is high.

The present invention discloses a method for hydrolyzing methyl methoxyacetate to produce methyl glycolate and glycolic acid, comprising: passing a raw material containing methyl methoxyacetate and water through a reactor filled with an acidic molecular sieve catalyst, reacting under certain reaction conditions to produce methyl glycolate and glycolic acid; wherein the acidic molecular sieve catalyst is filled in at least two spaced reaction zones of the reactor between upstream and downstream, methyl methoxyacetate is introduced into the at least two spaced reaction zones via different methyl methoxyacetate feed ports, and water is introduced into the at least two spaced reaction zones via a water feed port provided upstream of the reactor. This method improves the conversion rate of methyl methoxyacetate and the selectivity of methyl glycolate and glycolic acid, and reduces separation and circulation energy consumption.

The application discloses 2-(2,5-dihydroxyphenyl)-2-methoxy methyl acetate as well as a preparation method and application thereof, and relates to the technical field of marine fungus active ingredient production and application. The application discloses that 2-(2,5-dihydroxyphenyl)-2-methoxy methyl acetate has good anti-UVB-induced HaCaT cell oxidative damage activity, and the compound has low cytotoxicity, and has good development prospects in the preparation of cosmetics, medicines and health products for resisting skin damage.

The invention discloses methyl 2-(2, 5-dihydroxyphenyl)-2-methoxyacetate as well as a preparation method and application thereof, and relates to the technical field of production and application of active ingredients of marine fungi. Research finds that methyl 2-(2, 5-dihydroxyphenyl)-2-methoxyacetate has a good effect of resisting UVB induced HaCaT cell oxidative damage activity, and the compound is low in cytotoxicity and has a good development prospect in the aspect of preparing cosmetics, medicines and health care products for resisting skin damage.

The invention relates to the technical field of compound synthesis, in particular to a preparation method of methyl methoxyacetate. According to the method, a membrane contact reactor is adopted, an ultrathin heteropolyacid-ionic liquid composite catalytic membrane is constructed on a membrane-liquid interface, and CO is supplied in a segmented distribution mode in the length direction of the reactor. According to the method, spectral signals of CO dissolved in a liquid phase are monitored on line, and the CO permeation flux of each section is controlled in a closed-loop manner, so that the ratio r (z) of on-way local CO partial pressure to DMM concentration is maintained in a region beneficial to carbonylation reaction, and side reactions such as disproportionation and rearrangement of DMM are inhibited. The selectivity and yield of MMAc are remarkably improved under the same average CO pressure, and byproducts such as dimethyl ether and methyl formate are remarkably reduced. The heteropolyacid catalyst is fixed on a membrane interface through the low-volatility ionic liquid, loss of the catalyst is effectively prevented, stable reuse of the catalyst is achieved, and the method is suitable for continuous operation and good in long-term stability.

The present application discloses a preparation method for methyl glycolate. The preparation method comprises: subjecting a raw material containing methyl methoxyacetate, dimethyl ether and water to a hydrolysis reaction under predetermined reaction conditions by means of a reactor loaded with a solid acid catalyst, so as to obtain a product containing methyl glycolate. The addition of dimethyl ether in the preparation method of the present application can not only inhibit the hydrolysis reaction from generating dimethyl ether, but also convert dimethyl ether, a by-product of the reaction of carbonylation of methylal into methyl methoxyacetate, into methanol, thereby completely avoiding the output of dimethyl ether during the entire process of carbonylation / hydrolysis of methylal into methyl glycolate; moreover, the addition of dimethyl ether in the preparation method of the present application can promote the conversion of dimethyl ether into methanol during the hydrolysis reaction, which is conducive to the combined use of mature methanol-to-methylal techniques, thereby achieving the preparation of methyl glycolate from methanol, improving the reliability of the process flow and saving on costs.

The invention discloses a synthesis method of dimethyl malonate. The synthesis method comprises the following steps: methanol and methyl glycolate are subjected to a contact reaction with an etherification catalyst, an obtained product methyl methoxyacetate is subjected to a reaction with CO under the action of a carbonylation catalyst, and dimethyl malonate is obtained. According to the method disclosed by the invention, the dimethyl malonate is prepared through etherification-carbonylation two-step reaction, so that the utilization rate of the methyl glycolate and the yield of the dimethyl malonate are greatly improved.