55277-54-8Relevant articles and documents
Method for preparing alkane carboxylic acid by increasing alkane carbon chains
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Paragraph 0031; 0045; 0049, (2021/06/09)
The invention discloses a method for preparing alkane carboxylic acid by increasing alkane carbon chains. The method comprises the following steps: (1) carrying out Stork enamine alkylation on cyclopentanone or cyclohexanone and a secondary amine compound to generate a corresponding 1-position secondary amine substituted cyclopentene or cyclohexene crude product, namely Stork enamine; (2) carrying out electrophilic reagent reaction on the Stork enamine and acyl halide to form a 2-acyl cyclic ketone compound; and (3) carrying out ring opening on the 2-acyl cyclic ketone compound under the action of alkali to generate a carbonyl carboxylic acid compound, and carrying out a Wolff-Huang Minglong reduction reaction on the carbonyl carboxylic acid compound to obtain the corresponding alkane carboxylic acid. According to the method disclosed by the invention, cyclopentanone or cyclohexanone can be flexibly selected to meet the requirement of increasing different carbon numbers according to the required carbon number and different sources of target carburant alkane carboxylic acid or corresponding acyl halide. The method has the advantages of simple reaction process and no complex operation difficulty, and is suitable for industrial mass production.
A Short Route to Dihydrocapsaicinoids
Kaga, Harumi,Miura, Masakatsu,Orito, Kazuhiko
, p. 864 - 866 (2007/10/02)
Huang-Minlon reduction of 8-methyl-7-oxononanoic acid (4ba), obtained by the acylation of cyclohexanone enamine 2a with 2-methylpropanoyl chloride (1b) followed by ring cleavage of the resultant β-diketone 3ba affords 8-methylnonanoic acid (5ba), the chloride of which reacts readily with 4-hydroxy-3-methoxybenzylamine to give dihydrocapsaicin (7ba).This reaction sequence works also efficiently for other dihydrocapsaicinoids such as 7aa and 7bb.