Synthesis Of (R)-Ethyl Piperidine-3-acetate Hydrochloride Of Piperidine Derivatives And Functional-organic Moleculars

Piperidine derivatives are important new heterocyclic organic intermediates, mainly for the synthesis of rubber additives,pharmaceuticals and pesticides。In the rubber additives they are used for the synthesis of thiuram accelerators, such as TRA,PMTM,PTD。In the pharmaceutical industry they are used for the synthesis of anti-arrhythmia and anxiolytic drugs。In the pesticide industry they are used for the synthesis of some herbicides, such as piperazine grass Dan。Precisely because of its potential wide application, stimulate people to get interested in the synthetic research of piperidine derivatives。Ethyl (R)-piperidine-3-acetate is also an important medicine intermediate of piperidine derivatives, mainly used in the synthesis of neurological drugs, such as convulsions and anti-epileptic etc, thus many research groups have been involving in the synthesis of it。At present, becaues of no domestic reports to synthesis it, the actions to study the synthesis of Ethyl (R)-piperidine-3-acetate and realize industrialization, have important social and economic value。This paper reports a practical and scalable synthesis of Ethyl (R)-piperidine-3-acetate from commercially available 3-pyridylacetic acid hydrochloride in four steps with 76% overall yield。Ethyl (S)-piperidine-3-acetate can also be made similarly。The practical protocol was demonstrated in hundred grams scale。Key step in the synthesis is the successful hydrogenation of N-benzyl pyridinium salt of ethyl 3-pyridylacetate using relatively cheap Pd/C as a catalyst under mild reaction conditions; A one-pot reduction and.N-ethylation of the N-benzyl pyridinium salt with acetonitrile was demonstrated in large scale to give corresponding N-ethyl piperidine derivative in high yield。The paper first reports the synthesis of two functional organic molecules: (Z)-1-methoxy-2-(methoxymethyl)-3,3-diphenylprop-l-ene and 1-methoxy-2-(meth-oxymethyl)-3-(4-methylpentyl)benzene。The two molecules are new compounds。Presently I have completed their synthetic routes and got these two compounds by experiment。...