33 results about "Alpha-phenylethylamine" patented technology

This invention discloses a method for synthesizing (S)-(-)-gamma-lactone. The method comprises: (1) using (R)-(+)-alpha-phenylethylamine as the chiral resolving agent, and reacting with racemic gamma-hydroxy acid to obtain a pair of diastereotopic salts; (2) separating by crystallization; (3) acidifying and cyclizing to obtain chiral (S)-(-)-gamma-lactone. (S)-(-)-gamma-lactone is (S)-(-)-gamma-decalactone, (S)-(-)-gamma-undercalactone or (S)-(-)-gamma-dodecalactone. (S)- (-)-gamma-lactone has special fragrance, and can be used to manufacture high-grade essence.

The invention discloses a method for recovering pregabalin intermediate resolving agent (R)-(+)-alpha-phenylethylamine. The method comprises the following steps: a) adding an alkali to free mother liquor at a certain temperature for regulating the pH until the mother liquor is alkaline; b) adding an organic solvent to the system of which the pH is regulated previously for extraction; and c) blending the organic layer, carrying out reduced pressure distillation at a relatively low temperature to remove an extracting agent first, collecting the preceding fraction and then heating to carry out reduced pressure distillation again, thereby obtaining a fraction, namely the resolving agent (R)-(+)-alpha-phenylethylamine. The method has the advantages that the atom utilization rate is increased, the environmental pollution due to direct emission of materials in the mother liquor is avoided, and the production cost is greatly reduced, and the method has the characteristics of green chemistry. In a word, the method for recovering and recycling the (R)-(+)-alpha-phenylethylamine is green and environment-friendly, and low in cost and pollution.

The invention discloses a preparation method of a sitagliptin intermediate represented by formula 1. The preparation method comprises the following steps: step A, carrying out a reaction of beta-ketonic ester 2 with a chiral amine to obtain a chiral enamine 3, wherein the chiral amine is R(+)-alpha-phenylethylamine or D-(-)-phenylglycinol; step B, reducing the chiral enamine 3 to obtain a compound 4; step C, carrying out catalytic hydrogenation of the compound 4 to remove a chiral auxiliary group, and thus obtaining a compound 5; step D, protecting amino of the compound 5 by Boc to obtain a compound 6; and step E, hydrolyzing the compound 6 to obtain beta-amino acid 1. The method has the advantages of cheap and easily obtained chiral raw materials, short reaction route, simple operation, mild reaction conditions, no special requirements on equipment, high yield, low cost and small environment protection pressure, and has relatively good industrial application and economic value.

The invention provides a method for preparing (S)-azetidine-2-carboxylic acid, which is an important intermediate for synthesizing a plurality of inhibitors. The method comprises the following steps of: (1) reacting 1-benzyl-azetidine-2-carboxylic acid and D-alpha-phenylethylamine in a solvent to form a salt, cooling, crystallizing and filtering, and carrying out pH value regulation and salt removing on the obtained solid to obtain a (S)-1-benzyl-azetidine-2-carboxylic acid coarse product; (2) re-crystallizing the coarse product by a solvent to obtain pure (S)-1-benzyl-azetidine-2-carboxylic acid; (3) performing debenzylation on the product in the second step to obtain (S)-azetidine-2-carboxylic acid. The preparation method provided by the invention has low-price and easily available raw materials, is convenient to operate, is low in cost and high in product purity, and has a great implementation value.

The invention discloses a method for splitting cis-1-hydroxy-[1,1'-bi(cyclohexyl)]-2-formic acid and an intermediate. The method is characterized in that S-(-)-alpha-phenylethylamine or R-(+)-alpha-phenylethylamine is taken as a splitting agent for splitting the cis-1-hydroxy-[1,1'-bi(cyclohexyl)]-2-formic acid to obtain S-(-)-alpha-phenylethylamine salt of (1S, 2S)-1-hydroxy-[1,1'-bi(cyclohexyl)]-2-formic acid and R-(+)-alpha phenylethylamine salt of (1R, 2R)-1-hydroxy-[1,1'-bi(cyclohexyl)]-2-formic acid; high-pressure hydrogenation of a benzene ring and catalyzation of precious metal are avoided in the conventional preparation of rociverine single isomer. The S-(-)-alpha-phenylethylamine salt and the R-(+)-alpha phenylethylamine salt have the advantages of low cost, low process cost, environmental friendliness and suitability for industrial production.

The invention discloses a zinc nitride and copper nitride compound of chiral alpha-phenylethylamine, which comprises a (S) alpha-phenylethylamine zinc nitride and copper nitride compound and a (R) alpha-phenylethylamine zinc nitride and copper nitride compound, which are prepared from the alpha-phenylethylamine, zinc acetate dihydrate, copper acetate monohydrate and copper chloride dihydrate and have the following formulas. In the formulas, ML is Zn(OOCCH3)2, Cu(OOCCH3)2 or CuCl2. The compound serves as a chiral catalyst in a Henry reaction.