69750-34-1Relevant academic research and scientific papers
Preparation method of dimethyl 2, 6-naphthalate
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Paragraph 0113-0114; 0118-0119, (2021/06/02)
The invention discloses a preparation method of dimethyl 2, 6-naphthalate. Specifically, the preparation method of the dimethyl 2, 6-naphthalate disclosed by the invention comprises the following steps: carrying out esterification reaction on 2, 6-naphthalic acid and methanol under a pressurization condition in the presence of a catalyst, and filtering without further purification to obtain the dimethyl 2, 6-naphthalate, wherein the mass ratio of the methanol to the 2, 6-naphthalic acid is (3: 1)-(25: 1), the reaction temperature ranges from 100 DEG C to 150 DEG C. According to the preparation method disclosed by the invention, the operation is simplified, the yield of the dimethyl 2, 6-naphthalate is improved, and meanwhile, the purity of the dimethyl 2, 6-naphthalate is maintained.
Method for preparing high-purity naphthalic acid by taking beta-methylnaphthalene as raw material
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Paragraph 0032-0033; 0035-0036; 0038-0039, (2019/10/01)
The invention discloses a method for preparing high-purity naphthalic acid by taking beta-methylnaphthalene as a raw material. The method comprises the following steps of (1) preparation of an acylation solution, wherein propionyl chloride is added into nitrobenzene and anhydrous aluminium trichloride, and it is controlled that the temperature is below 0 DEG C, so that a mixed solution is mixed into a uniform and transparent solution; (2) an acylation reaction, wherein the acylation solution obtained in step (1) is added into a nitrobenzene solution of 2-methylnaphthalene dropwise, it is controlled that the temperature is below 0 DEG C, and the acylation reaction is carried out; (3) hydrolysis of an acylate, wherein distilled water is added into the product obtained in step (2) for cleaning until the pH value of a mixed solution is 6-7; (4) reduced pressure distillation, wherein the product obtained in step (3) is subjected to reduced pressure distillation, the acylate flows out at 165-180 DEG C, cooling is carried out, and a white solid is obtained; (5) purification of the acylate, wherein the product obtained in step (4) is purified by using a recrystallization method, 2-methyl-6-propiononaphthone is obtained, and vacuum drying is carried out; (6) an oxidation reaction, wherein the product obtained in step (5) is synthesized into 2,6-NDA through an air liquid phase oxidationreaction technology.
BIOSYNTHESIS OF AXENOMYCIN D: INCORPORATION OF 13C-LABELLED PRECURSORS INTO THE MENADIONE CHROMOPHORE, DESOXYSUGARS AND THE AXENOLIDE
Friese, V.,Boos, A.,Bauch, H.-J.,Leistner, E.
, p. 613 - 622 (2007/10/02)
Experiments on the biosynthesis of the menadione chromophore of axenomycin D in Streptomyces lisandri resulted in the specific incorporation of label from L-methionine, propionate, propionate, propionate, glycerol and glucose.The data indicate that the menadione chromophore is derived from a metabolite of the shikimate pathway.The mode of incorporation shows, however, that the biosynthesis of the menadione chromophore of axenomycin differs from the biosynthesis of the menadione chromophore of menaquinones.Key Word Index: Streptomyces lisandri; axenomycin; biosynthesis; 13C-NMR spectroscopy.
Sequential Acetalization-Pyrolysis of α-Acetylcinnamates and α-Acetylbenzalacetones. A Method for the Generation of 2-Carbonyl-Subsituted Naphthalenes
Zoeller, Joseph R.,Sumner, Charles E.
, p. 319 - 324 (2007/10/02)
Substituted 2-acetonaphthones and 2-naphthoate methyl esters can be generated from benzaldehydes in a sequence of three reaction steps.Knoevenagel condensation of a benzaldehyde with 2,4-pentandione of methyl acetoacetate yields α-carbonyl-substituted benzalacetones.The α-carbonyl-substituted benzalacetones are then cyclized to generate the α-carbonyl-substituted naphthalenes by a sequential acetalization with trimethyl orthoformate followed by subsequent pyrolysis of the dimethyl acetal either in the vapor phase at 475 deg C or by being heated in boiling 1-methylnaphthalene. 2-Acetonaphthones are obtained when 2,4-pentanedione is used and 2-naphthoate methyl esters are obtained from methyl acetoacetate.
