103-74-2Relevant articles and documents
Site-Selective Aliphatic C?H Silylation of 2-Alkyloxazolines Catalyzed by Ruthenium Complexes
Kon, Kazumasa,Suzuki, Hiroyuki,Takada, Kosuke,Kohari, Yoshihito,Namikoshi, Takeshi,Watanabe, Shinji,Murata, Miki
, p. 2202 - 2205 (2016)
The Ru-catalyzed dehydrogenative silylation of 2-alkyloxazolines with 1,1,1,3,5,5,5-heptamethyltrisiloxane took place site-selectively at methyl C(sp3)?H bonds located γ to the nitrogen atom of the oxazolyl groups. Pyridine and pyrazole rings could also be used as a directing group. A catalytic mechanism based upon successive σ-bond metathesis is proposed.
The benzyl can be selectively removed by visible light or near visible light. Method for protecting allyl and propargyl group
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Paragraph 0029, (2021/10/16)
The invention provides a method for selectively removing benzyl, allyl and propargyl protecting groups by visible light or near visible light, namely a substrate containing benzyl, allyl or propargyl protecting groups. The method has the advantages of simple operation, safe and clean visible light or near visible light as excitation conditions, cheap and easily available reagents, high reaction yield, high reaction chemistry and regional selectivity, and is suitable for selective removal of benzyl, allyl and propargyl protecting groups in various substrates.
Synthesis method of (2-hydroxyethyl)pyridine
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Paragraph 0040-0068, (2020/12/10)
The invention discloses a synthesis method of (2-hydroxyethyl)pyridine. The preparation method comprises the following step: reacting 2-methylpyridine with formaldehyde in a solvent under a pressure of 2-8 MPa and under the action of organic alkali so as to obtain (2-hydroxyethyl)pyridine, wherein the organic alkali is one or more selected from triethylene diamine, hexamethylenediamine, tetramethyl guanidine, 1,8-diazabicycloundec-7-ene and 1,5,7-triazabicyclo[4.4.0]deca-5-ene. When the method is used for preparing (2-hydroxyethyl)pyridine, reaction time is obviously shortened, a one-way conversion rate is high, and production cost can be saved.
Preparation method of orthographic optimizing betahistine hydrochloride
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Paragraph 0009, (2018/07/30)
The invention discloses a preparation method of orthographic optimizing betahistine hydrochloride, and relates to the field of drug preparation. The preparation method includes the steps: adding raw materials into a reaction bottle according to the feeding ratio (molar ratio) of 2-methylpyridine to paraformaldehyde of 1:0.57, leading in nitrogen, stirring mixture for 20 hours at the temperature of125 DEG C and at 4 barometric pressure, performing reduced pressure distillation, and collecting distillation cut at the temperature of 130-145 DEG C and under the pressure of 16mm mercury columns toobtain light-yellow oily 2-hydroxyethyl pyridine; adding the 2-hydroxyethyl pyridine into a three-opening bottle, adding sodium hydroxide according to the feeding ratio of 2-(2-Hydroxyethyl)pyridineto sodium hydroxide of 1:0.05, heating the mixture to reach 95-100 DEG C, stirring the mixture for 2 hours, removing a water layer, performing reduced pressure distillation on an oil layer, and collecting the distillation cut at the temperature of 65-70 DEG C and under the pressure of 17mm mercury columns to obtain 2-vinylpyridine. The preparation method is simple in technological process, safe tooperate and mild in reaction, production efficiency and product quality can be greatly improved, and production cost is reduced.