1048976-83-5Relevant articles and documents
Preparation method of N-substituted-tetrahydropyridine-3/4-boric acid/ester
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Paragraph 0023-0025, (2020/04/22)
The invention discloses a preparation method of N-substituted tetrahydropyridine-3/4-boric acid/ester, and belongs to the technical field of organic boric acid chemistry. The method comprises the following steps: carrying out a reaction on pyridine-3/4-boric acid/ester and a halide to form a quaternary salt, and reducing the quaternary salt with sodium/potassium borohydride in an aprotic solvent to generate N-substituted-tetrahydropyridine-3/4-boric acid/ester. According to the method, easily-synthesized pyridine-3/4-boric acid/ester is used as a raw material, the product can be obtained through two continuous steps, and the reaction selectivity is high, so that the defect that palladium-catalyzed coupling or ultralow temperature is needed when substituted piperidone is adopted as a raw material is overcome, the method is verified on the hectogram scale, and a concise and efficient synthesis path is provided for preparation of the compound.
New synthesis method of N-substituted-1,2,5,6-tetrahydropyridine-4-boronic acid pinacol ester
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Paragraph 0025; 0027-0028, (2019/12/25)
The invention discloses a new synthesis method of N-substituted-1,2,5,6-tetrahydropyridine-4-boronic acid pinacol ester. The new synthesis method of the N-substituted-1,2,5,6-tetrahydropyridine-4-boronic acid pinacol ester comprises the following three reaction steps: firstly, performing reaction on 4-bromopyridine hydrochloride and clR1 to prepare 4-bromine-N-substituted-pyridine chloride; then preparing N-substituted-piperidine-4-alkenyl bromide through NaBH4 reduction; finally, preparing the target product N-substituted-1,2,5,6-tetrahydropyridine-4-boronic acid pinacol ester through a Grignard method and methoxy boric acid ester. The synthesis route has the advantages of high universality, cheap and easily available raw materials, mild reaction condition, few byproducts, high yield andthe like, and the product has high economic property and strong market competitiveness and is suitable for industrialized production. The formula is as shown in the description, wherein R1=-Boc;-Cbz;-Bz;-Bn;-Fmoc;-Me;-Et;-iPr;-Ph.