184 results about "Methylating Agent" patented technology

The invention includes methods of processing an initial di-carbonyl compound by conversion to a cyclic compound. The cyclic compound is reacted with an alkylating agent to form a derivative having an alkylated ring nitrogen. The invention encompasses a method of producing an N-alkyl product. Ammonia content of a solution is adjusted to produce a ratio of ammonia to di-carboxylate compound of from about 1:1 to about 1.5:1. An alkylating agent is added and the initial compound is alkylated and cyclized. The invention includes methods of making N-methyl pyrrolidinone (NMP). Aqueous ammonia and succinate is introduced into a vessel and ammonia is adjusted to provide a ratio of ammonia to succinate of less than 2:1. A methylating agent is reacted with succinate at a temperature of from greater than 100° C. to about 400° C. to produce N-methyl succinimide which is purified and hydrogenated to form NMP.

This disclosure relates to a process of manufacturing para-xylene, comprising (a) contacting a pygas feedstock and methylating agent with a catalyst under reaction conditions to produce a product having para-xylene, wherein the product has higher para-xylene content than the para-xylene content of the pygas feedstock; and (b) separating the para-xylene from the product of the step (a), wherein the catalyst comprises a molecular sieve having a Diffusion Parameter for 2,2-dimethylbutane of about 0.1-15 sec−1 when measured at a temperature of 120° C. and a 2,2-dimethylbutane pressure of 8 kPa-a and the pygas comprises from about 1 to about 65 wt % benzene and from about 5 to 35 wt % toluene.

Applicants have discovered a method for the stereoselective and regioselective synthesis of 3α-hydroxy, 3β-methyl-5α-pregnan-20-one (ganaxolone) comprising reacting 5α-pregnane-3,20-dione; with an organometallic methylating agent in an inert solvent to provide a compound of the formula

The invention discloses a method for preparing methylnaltrexone bromide and belongs to the technical field of pharmaceutical engineering. The method comprises the following steps of: generating 3-O-t-butyl dimethyl silyl-naltrexone by taking naltrexone hydrochloride as a raw material, t-butyl dimethyl chlorosilane as a protection group and a dipolar aprotic solvent as a medium in the presence of organic base; reacting dimethyl carbonate serving as a methylating agent and the dipolar aprotic solvent serving as the medium with the dimethyl carbonate; and finally, reacting with solution of hydrobromic acid in the water serving as a medium, and distilling at reduced pressure to obtain the methylnaltrexone bromide. The protection group t-butyl dimethyl chlorosilane of phenolic hydroxyl is white solid, has no pungent odor, can generate stable intermediate products at normal temperature, has simple removal step, and is an ideal hydroxyl protective agent. The methylating agent dimethyl carbonate makes reaction environment-friendly, reaction yield higher, and technology simpler; the methylnaltrexone bromide is generated during deprotection; the steps are shortened; and the industrialized production is convenient.

A morphine component, e.g., a concentrate of poppy straw, is converted into codeine in high yield and high purity and in a highly controlled manner. The conversion process involves the following steps: (a) providing a solution or suspension of a morphine component in an inert solvent or a mixture of solvents; (b) methylating the resultant solution or suspension with a methylating agent in the presence of an alkaline ingredient; and (c) recovering the resultant codeine as the free base or as a salt.