504-02-9Relevant articles and documents
Method for preparing 1, 3-cyclohexanedione
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Paragraph 0026-0032, (2021/09/04)
The invention discloses a method for preparing 1, 3-cyclohexanedione. The method comprises the following steps: 1) dissolving acetylacetone and a catalyst in a solvent, adding acrylate into a constant-pressure dropping funnel, and dropwise adding acrylate into a reaction system, after drop-by-drop adding, heating to 60-80 DEG C, and continuously reacting for 0.5-1 hour; and 2) after the reaction is finished, cooling to 40 DEG C, adding a solid condensing agent, heating the reaction liquid to 40-50 DEG C, continuously reacting for 1-1.5 hours, concentrating under reduced pressure to remove the solvent and methyl acetate and other low-boiling-point byproducts generated by the reaction, then adding a small amount of water, adjusting the pH value to 1-2 by using hydrochloric acid (1.1-1.2 equivalent), cooling to separate out a product, centrifuging, leaching by using a small amount of ice water, carrying out pulping treatment by using ethyl acetate, filtering and drying to obtain the 1, 3-cyclohexanedione product.
Preparation method of 1,3-cyclohexanedione
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Paragraph 0068-0095, (2020/07/13)
The invention relates to the field of organic synthesis, and discloses a preparation method of 1,3-cyclohexanedione. The method comprises the following steps: 1, in the presence of water, hydrogenating resorcinol to obtain a reaction solution containing a compound represented by the following formula (1), acidifying the reaction solution to obtain an acidified solution, and crystallizing the acidified solution to obtain a 1,3-cyclohexanedione product and an acidified mother liquor; 2, in the presence of an organic solvent, enabling the acidified mother liquor to be in contact with a complexingagent to complex 1,3-cyclohexanedione with the complexing agent, and obtaining an organic phase; 3, making the organic phase obtained in the step 2 contact the reaction solution, adjusting the pH value to 7-14 so as to make the 1,3-cyclohexanedione be dissociated from the complexing agent, and obtaining a water phase; and 4, adjusting the pH value of the water phase obtained in the step 3 to 1.0-2.5, and carrying out solid-liquid separation to obtain the 1,3-cyclohexanedione product. The preparation method disclosed by the invention has the advantages of high purity and high yield of the prepared 1,3-cyclohexanedione.
Rapid and Multigram Synthesis of Vinylogous Esters under Continuous Flow: An Access to Transetherification and Reverse Reaction of Vinylogous Esters
Mohanta, Nirmala,Chaudhari, Moreshwar B.,Digrawal, Naveen Kumar,Gnanaprakasam, Boopathy
, p. 1034 - 1045 (2019/05/24)
An environmentally benign approach for the synthesis of vinylogous esters from 1,3-diketone and its reverse reaction under continuous-flow has been developed with alcohols in the presence of inexpensive Amberlyst-15 as a catalyst. This methodology is highly selective and general for a range of cyclic 1,3-dicarbonyl compounds which gives a library of linear alkylated and arylated vinylogous esters in good to excellent yield under solvent and metal free condition. Furthermore, the long-time experiment in a continuous-flow up to 40 h afforded 8.0 g of the vinylogous ester with turnover number (TON) = 28.6 and turnover frequency (TOF) = 0.715 h-1 using Amberlyst-15 as a catalyst. Furthermore, a continuous-flow sequential transetherification of vinylogous esters with various alcohols has been achieved in high yield. Reversibly, this vinylogous ester was deprotected or hydrolyzed into ketone using environmentally benign water as a solvent and Amberlyst-15 as a catalyst under continuous-flow process.