313643-49-1Relevant articles and documents
Mechanism of α-acetyl-γ-butyrolactone synthesis
Wang, Wei,Zhang, Sheng-Wan,Li, Mei-Ping,Ren, Ying-Yu
, p. 624 - 630 (2013)
The mechanism of α-acetyl-γ-butyrolactone (ABL) synthesis from γ-butyrolactone (GBL) and ethyl acetate (EtOAc) was explored by detecting the material changes involved and the enthalpies of formation of the synthons, products, and possible intermediates were calculated using the density functional theory. GBL forms a carbanion of γ-butyrolactone by losing an α-H under strongly alkaline conditions. ABL is then obtained via two reaction mechanisms. One of the reaction mechanisms involves direct reaction of the carbanion of GBL with EtOAc to produce ABL. The other involves the formation of a carbanion of α-(2-hydroxy-tetrahydrofuran-2-yl)-γ- butyrolactone through the reaction of two molecules of GBL, and the subsequent combination of this anion with EtOAc to produce ABL. ABL is thus formed through the above two kinds of competitive ester condensation reactions. It is unnecessary to take into account synthons' local thickness, and their self-condensation under these conditions. Both reactions of the carbanion of GBL with EtOAc and GBL are exothermic, so the control of their reaction rate is the key to their security. Considering the reasons above, this work applied synthon as the solvent, and avoided environmental pollution by alkylbenzene; also, accidents such as red material and fire were avoided by specific surface area of sodium metal control. Effective isolation of the organic and aqueous phases was performed using the salting out method. Thus, an environmentally friendly, safe, simple, and efficient new method for the synthesis of ABL with the yield higher than 90 % has been established.
Application of liquid sodium methoxide in synthesis of alpha-acetyl-gamma-butyrolactone and synthesis method of alpha-acetyl-gamma-butyrolactone
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Paragraph 0085-0106, (2021/05/08)
The invention provides application of liquid sodium methoxide in synthesis of alpha-acetyl-gamma-butyrolactone and a synthesis method of the alpha-acetyl-gamma-butyrolactone, and relates to the technical field of organic synthesis. The synthesis method of the alpha-acetyl-gamma-butyrolactone comprises the following steps: (a) performing pre-acylation reaction on an acetate compound and gamma-butyrolactone; (b) adding liquid sodium methoxide into the reaction liquid in the step (a) to carry out mixed reaction; (c) after the reaction in the step (b) is finished, concentrating and collecting methanol, and transferring the concentrated reaction liquid into an acylation kettle; (d) supplementing the acetate compound into the acylation kettle for acylation reaction; (e) performing neutralizing, filtering and concentrating to obtain an alpha-acetyl-gamma-butyrolactone crude product. According to the method, liquid sodium methoxide is used for replacing solid sodium methoxide for acylation synthesis, so that liquification and sealing of feeding are realized, the on-site feeding risk is reduced, and the synthesis yield is increased to 96% or above.
Preparation method of alpha-acetyl-gamma-butyrolactone
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Paragraph 0053-0123, (2020/09/16)
The invention relates to the field of organic synthesis, and discloses a preparation method of alpha-acetyl-gamma-butyrolactone. The method comprises the following steps: (1) gamma-butyrolactone, CH3COOR1 and R2ONa are subjected to acylation reaction to obtain a material containing alpha-acetyl-gamma-butyrolactone sodium salt, and R1 and R2 are respectively independently C1-C4 alkyl; and (2) in the presence of water, the material containing the alpha-acetyl-gamma-butyrolactone sodium salt is enabled to be in contact with CO2 gas to generate neutralization reaction. The method also has the advantage of higher yield under the condition of ensuring safety, and provides convenience for large-scale production of alpha-acetyl-gamma-butyrolactone.
Process for dissociating acetamidine hydrochloride with alpha-acetyl-gamma-butyrolactone sodium salt
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Paragraph 0064-0120, (2019/03/25)
The invention relates to the technical field of vitamin B synthesis intermediates, in particular to a process for dissociating acetamidine hydrochloride with alpha-acetyl-gamma-butyrolactone sodium salt. The process comprises the following steps: making alpha-acetyl-gamma-butyrolactone sodium salt react with the acetamidine hydrochloride and separating products to obtain acetamidine and alpha-acetyl-gamma-butyrolactone. According to the process, the intermediate product alpha-acetyl-gamma-butyrolactone sodium salt in the synthesis step of the alpha-acetyl-gamma-butyrolactone reacts with the acetamidine hydrochloride, the alpha-acetyl-gamma-butyrolactone sodium salt utilize hydrochloric acid coordinated in the acetamidine hydrochloride to achieve the effect that the alpha-acetyl-gamma-butyrolactone sodium salt produces the alpha-acetyl-gamma-butyrolactone, and the hydrochloric acid in the acetamidine hydrochloride is removed to form acetamidine. Synchronous production of two target products is achieved, the steps are saved, and the process is environmentally friendly and increases the revenue.
Preparation method for Alpha-acetyl-Gamma-butyrolactone
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Paragraph 0013-0018, (2020/05/19)
The invention discloses a preparation method for Alpha-acetyl-Gamma-butyrolactone, and belongs to the technical field of compound synthesis. The method comprises the following steps: under the conditions of an organic solvent, using Gamma-butyrolactone and acetaldehyde as initial raw materials, using inorganic base as a catalyst, performing an acetylation reaction, adjusting a pH value of reactionliquid by using diluted acid until the reaction liquid is neutralized, and post-processing to obtain the Alpha-acetyl-Gamma-butyrolactone. The method has the characteristics of economical feasibility, higher yield, safety and environmental protection, and is suitable for industrialization.
Method for preparing alpha-acetyl-gamma-butyrolactone
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Paragraph 0019-0021; 0023; 0025; 0027; 0029; 0031; 0033, (2018/11/03)
The invention discloses a method for preparing alpha-acetyl-gamma-butyrolactone. The method comprises the following steps: adding ethyl acetate and sodium carbonate into a three-necked flask, dropwiseadding gamma-butyrolactone at the temperature of 44 to 46 DEG C, stirring, mixing the ethyl acetate and liquid aldehyde, dropwise adding a reaction solution, uniformly mixing, stirring and reacting for 1.5 to 2.5 hours at the temperature of 54 to 58 DEG C, adding the reaction solution into a high-pressure kettle, reacting for 5 to 6 hours at the temperature of 80 to 85 DEG C, cooling to room temperature, adding the reaction solution into a three-necked flask, dropwise adding sulfuric acid at 3 to 5 DEG C to adjust the pH to be 6 to 7, precipitating solids in the dropwise addition process, after the addition is ended, stirring for 11 to 13 hours, re-testing the pH which is unchanged, filtering to remove the solids, washing a filter cake by using ethyl acetate, performing the decompressionrotary evaporation, removing the ethyl acetate until no fraction is outputted, obtaining a crude product, and performing the direct decompression rectification for the crude product. The preparation method is easy in obtaining raw materials, cheap in raw materials, easy in operation, higher in yield, and suitable for industrialized production.
Synthesis method for alpha-acetyl gamma-butyrolactone
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Paragraph 0022-0047, (2018/04/21)
The invention relates to the field of synthesis of organic intermediates of prothioconazole, in particular to a synthesis method for alpha-acetyl gamma-butyrolactone. The synthesis method includes thefollowing steps of (1) slowly heating a reactor to 75 DEG C, and adding gamma-butyrolactone, ethyl acetate and sodium ethoxide for reflux reaction for 10 hours to obtain a sodium salt of alpha-acetylgamma-butyrolactone and a by-product ethanol; (2) distilling the product obtained in the step (1) to remove the ethanol and excess ethyl acetate, adjusting the pH of the residue to 3-4 with dilute sulfuric acid, standing for liquid separation, removing aqueous phase, and performing vacuum distillation in an organic phase at a pressure of 0.1 MPa and a temperature of 65-70 DEG C to obtain alpha-acetyl gamma-butyrolactone. The synthesis method uses a reaction base material ethyl acetate as a base solvent and uses sodium ethoxide as a condensing agent, has mild reaction conditions and improved safety, avoids pollution caused by adopting additional solvents such as benzene solvent and the like, and has good safety, simple post-treatment method, high yield of alpha-acetyl gamma-butyrolactone above 90%, and high purity of alpha-acetyl gamma-butyrolactone above 98%.
Method for preparing alpha-acetyl-gamma-butyrolactone
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Paragraph 0019-0021, (2018/07/06)
The invention discloses a method for preparing alpha-acetyl-gamma-butyrolactone and relates to the technical field of chemical product preparation. The method comprises the following steps: by takingsolid sodium methoxide as a catalyst and gamma-butyrolactone and ethyl acetate as initial raw materials, implementing an acetylation reaction, after the reaction is completed, concentrating a reactionliquid, and separating an alpha-acetyl-gamma-butyrolactone sodium solid; implementing pulping and washing on the alpha-acetyl-gamma-butyrolactone sodium solid by using a second organic solvent in which the alpha-acetyl-gamma-butyrolactone sodium solid is not dissolvable; putting the washed alpha-acetyl-gamma-butyrolactone sodium solid into a third organic solvent, adjusting the pH value to 6-7 byusing an acid solution, stirring, filtering, and implementing vacuum distillation on filtrate, thereby obtaining alpha-acetyl-gamma-butyrolactone. The method has the characteristics of being short inpurification time, low in energy consumption, simple in preparation equipment, concise in operation, economically feasible, high in product purity, relatively high in yield, good in environment protection, and the like.
Catalytic decarboxylative alkenylation of enolates
Schroeder, Sybrin P.,Taylor, Nicholas J.,Jackson, Paula,Franckevicius, Vilius
supporting information, p. 3778 - 3781 (2013/08/23)
A palladium-catalyzed decarboxylative alkenylation of stabilized enolates has been developed, which gives rise to alkenylated dicarbonyl products from enol carbonates regioselectively with concomitant installation of a quaternary all-carbon center. The broad scope of the reaction has been demonstrated by successfully utilizing a range of enolates and external phenol nucleophiles.
An enantio-and diastereocontrolled synthesis of (-)-salinosporamide A
Sato, Yosuke,Fukuda, Hayato,Tomizawa, Masaki,Masaki, Tomohito,Shibuya, Masatoshi,Kanoh, Naoki,Iwabuchi, Yoshiharu
scheme or table, p. 2239 - 2246 (2011/04/15)
The enantio-and diastereocontrolled total synthesis of (-)-salinosporamide A, a potent 20S proteasome inhibitor, was accomplished through organocatalytic aldolization, diastereoselective Claisen condensation, a Rh-catalyzed Reformatsky reaction, and an AZADO-catalyzed oxidative β-lactonization reaction as the key reactions. The Japan Institute of Heterocyclic Chemistry.
