7 results about "Sandmeyer reaction" patented technology

The invention discloses a preparation method of an SGLT2 inhibitor key intermediate, and belongs to the technical field of medicinal chemistry. The preparation method comprises the following steps: 1) reacting a compound B with trimethylchlorosilane under an alkaline condition to generate a compound C; 2) reacting the compound C with an aldehyde group reagent on an aromatic ring to generate a compound D; 3) reacting the compound E with a bromination reagent to generate a compound F; 4) preparing the compound F into a Grignard reagent to generate a compound G; 5) carrying out addition reaction on the compound D and a compound G to generate a compound H; and 6) carrying out dehydroxylation and trimethylsilyl protection on the compound H to generate a compound A. According to the preparation method, the risk caused by amplification of the Sandmeyer reaction in the original route is avoided, and meanwhile, the preparation cost of the key intermediate is greatly reduced.

The invention relates to a synthetic method of a deuterated methyl selenide compound, which is characterized in that aromatic amine and deuterated methyl selenyl benzene sulfinate are subjected to Sandmeyer reaction in an organic solvent under the air condition and the action of tert-butyl nitrite to obtain the deuterated methyl selenide compound. The method has the advantages of simple reaction conditions and high product yield and purity, develops a new synthesis route and method for preparation of the deuterated methyl selenide compound, and has good application potential and research value.

The invention relates to the technical field of 7-methylisatin synthesis, in particular to a 7-methylisatin synthesis method, which comprises the following steps of: 1, data collection and model rehearsal; step 2, activation and pretreatment of the raw materials: a, diazotization reaction; b, carrying out a Sandmeyer reaction; c, carrying out Friedel-Crafts cyclization reaction; step 4, product purification treatment; 5, resource recycling of the waste materials; the system breaks through the limitation of a traditional experience-dependent process, a prediction-optimization-regulation intelligent closed loop is formed through deep fusion of a machine learning model and real-time process control, the system not only can accurately simulate a complex reaction path and globally optimize parameters, but also can dynamically adjust the production process according to online monitoring feedback, and the production efficiency is improved. Therefore, the self-adaptive optimization of the process is fundamentally realized, and the product yield and the excellent stability between batches are remarkably improved.

The invention discloses a synthetic method of a photoelectric material intermediate 1-[3, 5-bis (1-methyl ethyl) [1, 1 '-biphenyl]-4-yl]-2-bromo-1H-benzimidazole, which comprises the following steps: taking 2, 6-diisopropylaniline as an initial raw material, and sequentially carrying out free radical reaction, coupling reaction, Sandmeyer reaction, Wollman reaction and the like to obtain the 1-[3, 5-bis (1-methyl ethyl) [1, 1'-biphenyl]-4-yl]-2-bromo-1H-benzimidazole, namely the 1-[3, 5-bis (1-methyl ethyl) [1, 1 '-biphenyl]-4-yl]-2-bromo-1H-benzimidazole. The compound is 1, 1 '-biphenyl]-4-yl]-2-bromo-1H-benzimidazole. The synthesis method disclosed by the invention is relatively low in synthesis cost, simple in post-treatment method and high in yield, can be used for industrial production, conforms to the green chemical development trend, reduces the production cost of the whole process to the greatest extent, and has extremely high application value.

The invention relates to the technical field of pesticide preparation, and particularly discloses a novel preparation method of a key intermediate 1-(2, 4, 6-trichlorophenyl)-propyl-2-ketone of a bactericide pydiflumetofen. The method comprises the following steps: by taking 3, 5-dichloro-4-fluoronitrobenzene as a starting raw material, sequentially carrying out four-step unit reactions: reacting with ethyl acetoacetate under an alkaline condition to prepare 2-(2, 6-dichloro-4-nitrophenyl)-3-oxobutyric acid ethyl ester, and reacting with ethyl acetoacetate under an alkaline condition to prepare 2-(2, 6-dichloro-4-nitrophenyl)-3-oxobutyric acid ethyl ester; carrying out degreasing under an acidic condition, so as to obtain 1-(2, 6-dichloro-4-nitrophenyl)-propyl-2-ketone; reducing the nitro group to obtain 1-(4-amino-2, 6-dichlorophenyl)-propyl-2-ketone; and performing Sandmeyer reaction to obtain a target product. The preparation method is novel in synthetic route, few in side reaction and high in total yield, the content of a target product is larger than 99%, the preparation method is suitable for industrial production, and a key support is provided for industrialization of pydiflumetofen.

The invention discloses a preparation method of an LH-1801 key intermediate impurity, and belongs to the technical field of medicine synthesis. The preparation method comprises the following steps: firstly, carrying out diazotization reaction on a compound 1 and sodium nitrite under an acidic condition, and then carrying out Sandmeyer reaction on the compound 1 and cuprous bromide to obtain a compound 2; preparing acyl chloride from the compound 2 and an organic solvent under the action of chloride, and then carrying out Friedel-Crafts acylation reaction on the acyl chloride and a compound 3 in the presence of a catalyst to obtain a compound 4; and finally, carrying out reduction reaction on the compound 4 under the action of a reducing agent to obtain a compound 5. According to the method, raw materials are easy to obtain, the synthesis process is simple, repeatability is good, the purity of the obtained LH-1801 key intermediate impurity is high, the LH-1801 key intermediate impurity can serve as a reference substance to be used for quality research of the LH-1801 key intermediate, guarantee is provided for safe medication of LH-1801, and the practical value is high.

This invention belongs to the field of organic synthesis technology and relates to a method for synthesizing 3,4-difluoro-2-methoxyphenylacetic acid, comprising the following steps: S1 Using 3,4-difluoro-2-methoxyaniline and a diazotizing reagent as raw materials, a diazotization reaction is carried out under the action of a copper catalyst and an inorganic acid to obtain the 3,4-difluoro-2-methoxyaniline diazonium salt; subsequently, a Sandmeyer reaction is performed with bromine to obtain 6-bromo-2,3-difluoroanisole; S2 The 6-bromo-2,3-difluoroanisole obtained in step S1 is reacted with diethyl malonate under the action of a ferricyanide to obtain 2-(3,4-difluoro-2-methoxyphenyl)malonic acid; S3 The 2-(3,4-difluoro-2-methoxyphenyl)malonic acid obtained in step S2 is reacted with concentrated sulfuric acid to obtain 3,4-difluoro-2-methoxyphenylacetic acid. This invention features mild reaction conditions, high yield, and high purity, making it suitable for industrial production.