4890-85-1Relevant articles and documents
Regenerative role of the red phosphorus in the couple 'HIaq/Pred'
Albouy, Dominique,Etemad-Moghadam, Guita,Vinatoru, Mircea,Koenig, Max
, p. 295 - 299 (1997)
The synthesis of ortho-substituted benzoic acid 3 from benzalphthalide 1 in the presence of 'hydriodic acid-red phosphorus' (HIaq/Pred) occurs via the formation of benzylphthalide 2 as reaction intermediate. Its preparation is optimized by use of the 'supported reaction in dry media' process (Silica/HIaq) under microwave irradiation for 8 min. The role of the red phosphorus in the reduction reaction is elucidated: it intervenes in a catalytic cycle by an oxido-reductive disproportionation with the liberated iodine, affording either hypophosphorous acid in aqueous media, or P2I4 in anhydrous media with concomitant regeneration of HI. Thus, the presence of Pred in the couple 'HIaq/Pred' allows recycling of the hydriodic acid and enhances its reducing efficiency.
Cooperative iodine and photoredox catalysis for direct oxidative lactonization of carboxylic acids
Duhamel, Thomas,Mu?iz, Kilian
, p. 933 - 936 (2019/01/23)
A new method for the formation of γ- and δ-lactones from carboxylic acids through direct conversion of benzylic C-H to C-O bonds is described. The reaction is conveniently induced by visible light and relies on a mild cooperative catalysis by the combination of molecular iodine and an organic dye.
Preparation method of carboxylic acid compound
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Paragraph 0113; 0211-0213, (2017/08/29)
The invention provides a preparation method of a carboxylic acid compound. The preparation method comprises the following step of taking a lactone component to react with hydrogen in the presence of a compound catalyst to obtain the carboxylic acid compound. The compound catalyst comprises a hydrogenation catalyst and Lewis acid. In the presence of the compound catalyst comprising the hydrogenation catalyst and the Lewis acid, the lactone component is subjected to hydrogenation ring-opening reaction to obtain the carboxylic acid compound. The preparation method has the advantages of moderate reaction conditions and high yield; compared with a traditional method, less byproducts are generated, green and chemical requirements are met and the industrial value is better.