- Synthetic method for glufosinate ammonium
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The invention relates to a synthetic method for glufosinate ammonium. The synthetic method comprises the following steps: single-bromine substitution, amination, amino protection, chlorination ring opening, Arbuzov reaction and acidizing hydrolysis ammoniation; the single-bromine substitution means triggering alpha-site single-bromine substitution betweengamma-butyrolactone I and bromine under theexistence of catalyst and performing reduced pressure distillation, thereby acquiring a pure intermediate II alpha-bromine-gamma-butyrolactone; phosphorus tribromide is served as the catalyst; amination means triggering amination reaction between alpha-bromine-gamma-butyrolactone II and ammonium hydroxide, and then adding hydrochloric acid and reflowing, thereby acquiring an intermediate IIIalpha-amino-gamma-butyrolactone hydrochloride. The invention has the beneficial effects: 1) low-costgamma-butyrolactone is taken as a raw material, is subjected to single-bromine substitution with bromineand then is subjected to amination reaction with ammonium hydroxide; the adopted raw materials are low-cost and easily acquired; reaction conditions are mild; operation is simple and convenient; safety is high; amplifying production is feasible; reaction yield is high; product purity is high; cost is greatly lowered; the synthetic method is suitable for industrial production.
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Paragraph 0044; 0045
(2019/02/04)
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- A cogeneration process for producing sulfur and sulfur on behalf of acetate acid diester method (by machine translation)
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The invention technical field of chemical synthesis, in particular relates to a methionine as raw material production process for producing sulfur and sulfur on behalf of acetate acid diester method. The invention states the payment proportional to production for preparing sulfur and sulfur on behalf of acetate acid diester method, in order to methionine and halogenated acetic acid as the raw material, the preparation comprising a homoserine lactone hydrohalide salt (IV), a sulfur acetate (I) and sulfur on behalf of the b b acid diester (II) of the three kinds of chemical products, and each between the products easy to separate and purify. (by machine translation)
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Paragraph 0055; 0057
(2018/12/02)
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- Synthesis method of 2-amino-gamma-butyrolactone hydrochloride
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The invention discloses a synthesis method of 2-amino-gamma-butyrolactone hydrochloride (I) for a kind of important chemical, dye, pesticide and medical intermediates. The synthesis method includes the following steps: taking a gamma-butyrolactone compound (II) and a nitroso ester compound (III) as raw materials to react with each other to obtain 2-(hydroxyl imino)-gamma-butyrolactone (IV), and subjecting the compound (IV) to reduction reaction and acidification to obtain the 2-amino-gamma-butyrolactone hydrochloride (I). The method used for preparing the product compound (I) is mild in condition, simple to operate, high in yield, low in environmental pollution, easier for industrial production and the like.
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Paragraph 0025; 0026; 0027
(2017/01/02)
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- Preparation of α-(2,2-diphenylhydrazino)lactones and related compounds by radical cyclization: Use of glyoxylic acid hydrazone derivatives
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Glyoxylic acid diphenylhydrazone (2a) and the corresponding O-benzyloxime (2b) are easily esterified in high yield by β-bromo alcohols. The resulting esters undergo radical cyclization to α-(2,2-diphenylhydrazino)- or α-[(phenylmethoxy)amino]lactones on treatment with tributyltin hydride. Esters for radical cyclization were also made using a β-(phenylseleno) alcohol and an enol ether. Several derivatives of glyoxylic acid were evaluated, but none was as effective as 2a or 2b. The imine 28 was prepared by an indirect route; it undergoes radical cyclization with displacement of the nitrogen substituent (28 → 30) so that an α-amino lactone can be generated by acid hydrolysis of the cyclization product.
- Clive,Zhang,Subedi,Bouetard,Hiebert,Ewanuk
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p. 1233 - 1241
(2007/10/03)
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- Preparation of α-(2,2-diphenylhydrazino)- and α-(benzyloxyamino)-lactones by radical cyclization: Use of glyoxylic acid diphenylhydrazone and glyoxylic acid 0-benzyloxime
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Glyoxylic acid diphenylhydrazone (2, Y = NPh2) and the corresponding O-benzyloxime (2, Y = OBn) are easily esterified in high yield by β-bromo alcohols, and the resulting esters undergo radical cyclization to α-(2,2-diphenylhydrazino) or α-(ben
- Clive, Derrick L. J.,Zhang, Junhu
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p. 549 - 550
(2007/10/03)
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- Asymmetric Synthesis of α-Amino Acids via Cationic Aza-Cope Rearrengements
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Ene-iminium intermediates resulting from reaction between glyoxal and β-amino alcohols rearrange by an aza-Cope process.Three different tandem reactions are thus carried out; their first component is this cationic rearrangement, the second step being either an iminium hydrolysis, a nucleophile-induced ene-iminium cyclization or a Mannich reaction.The last two sequences lead to homochiral proline derivatives.
- Agami, Claude,Couty, Francois,Lin, Jing,Mikaeloff, Axelle,Poursoulis, Michel
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p. 7239 - 7250
(2007/10/02)
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