- METHOD FOR PREPARING APRONAL AND INTERMEDIATE THEREOF
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PROBLEM TO BE SOLVED: To provide a simple, cost-effective and improved method for synthesizing apronal and an intermediate alkyl 2-isopropyl-4-pentenoate used in the synthesis of allylisopropylacetylurea of apronal. SOLUTION: There is provided a method including a step of reacting an alkyl 2-isopropyl-4-pentenoate with an alkali metal salt such as sodium urea in the presence of an aprotic polar solvent or a mixture of solvents to obtain apronal of the following formula (1). In addition, the present invention also includes a method for preparing the intermediate alkyl 2-isopropyl-4-pentenoate by dealkoxycarbonylation of dialkylallyl isopropyl malonate. SELECTED DRAWING: None COPYRIGHT: (C)2020,JPOandINPIT
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- Synthesis method of apronal
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Belonging to the technical field of drug synthesis, the invention discloses a synthesis method of apronal. The method adopts commercial raw material isopropyl malonate diester as the starting raw material for reaction with allyl bromide or allyl chloride under an alkaline condition by one-pot process to generate dimethyl allyl isopropylmalonate, then hydrolysis is carried out to generate allyl isopropylmalonic acid, which is subjected to thermal decomposition to be further converted into acyl chloride for reaction with urea, thus obtaining apronal. The synthetic route adopted by the inventiononly needs two or three steps, the whole process is in simple in operation, the materials are easily available, the cost is low, and the yield is high, therefore the method is suitable for industrialproduction.
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- Synthesis method of apronal
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The invention discloses a synthesis method of apronal. The synthesis method takes isopentanoic acid or isopentanoate which is commercially cheap and available as a synthesis raw material and comprises the following steps: enabling the synthesis raw material and allyl bromide to react under an alkaline condition to generate 2-isopropyl-4-pentenoic acid or 2-isopropyl-4-pentanoate; hydrolyzing the 2-isopropyl-4-pentanoate under the alkaline condition to generate the 2-isopropyl-4-pentenoic acid; then transforming the 2-isopropyl-4-pentenoic acid into acyl chloride and enabling the acyl chloride to react with urea to obtain the apronal. According to the synthesis method disclosed by the invention, a synthesis route can realize medium-scale preparation of the apronal, with the need of two-step or three-step chemical transformation; the whole synthesis route is simple and efficient, simple and convenient to operate, low in cost and high in yield so that the synthesis method is suitable for large-quantity synthesis of the apronal.
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Paragraph 0027; 0028; 0031
(2018/04/01)
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