CN1221543C - Preparation method of d-alpha tocopherol - Google Patents

Abstract

The present invention relates to a method for preparing d-alpha tocopherol, which belongs to the field of natural medicine preparing technology. The method aims to solve the technical problem that a method for preparing d-alpha tocopherol with the advantages of simple requirement for technological conditions, easy realization of industrialization, high isomer conversion rate and high yield. The method has a technical scheme: (1) the methylation reaction of mixed tocopherol: the mixed tocopherol is dissolved in organic solvent according to a proportion of 1:2 to 5; after dissolved, a catalyst is put in the mixed tocopherol according to a proportion of 1:1.5 to 3; formaldehyde solution is used as a methylating agent to be stirred and refluxed in a reaction kettle for 3 to 4 hours, and reaction temperature at normal pressure is from 40 to 70 DEG C; (2) water washing, delamination and crystallization: methylation reaction material solution is washed by water for three times in a water washing kettle; the product is settled to be delaminated; after water layer is separated, the product is heated to 50 to 70 DEG C; the solvent is distilled off to obtain the d-alpha tocopherol. The conversion rate of the d-alpha tocopherol is as high as more than 99%, and the yield of the total reactive tocopherol can achieve 90 to 92%.

Description

The preparation method of d-alpha-tocopherol

Technical field: the preparation method who the present invention relates to a kind of medicinal natural VE.

Background technology: it is relevant with its reproductive function because of early discovery for vitamin-E, so claim tocopherol again.The crude substance that natural VE mainly extracts from plant deodorization distillate (common name DFCC D oil), it is a kind of tocopherol of mixed type, generally contain α, β, four kinds of tocopherol active isomers of γ, δ in it, in U.S. FCC pharmacopeia, natural vitamin E product is formed difference according to the content of wherein α, β, γ, four kinds of tocopherol active isomers of δ be divided into two kinds of low α type and high alpha type natural vitamin Es.Low alpha type natural vitamin E is that concentrated purification of DD oil makes, and the α type tocopherol of physiologically active only accounts for 10-20% in total tocopherol, and therefore, the Chang Zuowei antioxidant is used for the additive of food and feed.High alpha type vitamin E is then made raw material with low alpha type natural vitamin E, and the β that biological value in the mixture is low, γ, methyltocol are converted into high α type, form complete α type dextrorotation tocopherol.This have a tocopherol of high biological value, is usually used in the nutritive health-care of human body and the medicine of disease treatment.At present, the production technology that the mixed tocopherol isomer is converted into the d-alpha-tocopherol generally adopts two-step approach: the first step elder generation methylol, chloromethyl or amine-methylated, and then carry out high-pressure hydrogenation and reduce, not only technological process is comparatively complicated for it, the stable control of difficult quality, and the transformation efficiency of isomer is not high, and yield is also low; Simultaneously, because the corrodibility of reaction pair high-tension apparatus is difficult to overcome, so be difficult to realize suitability for industrialized production.

Summary of the invention: technical problem to be solved by this invention is: overcome the deficiency of above-mentioned prior art, provide a kind of processing condition to require to realize simply, easily the preparation method of the d-alpha-tocopherol that suitability for industrialized production and isomer transformation efficiency and yield are all higher.A kind of preparation method of d-alpha-tocopherol comprises methylation reaction and washing, separating step, it is characterized in that its processing condition:

Mixed tocopherol is in 1: the ratio of 2-5 is dissolved among the organic solvent, and dissolving back is by the ratio input catalyzer tin protochloride of mixed tocopherol 1: 0.8 or 0.33; Do methylating agent in reactor stirring and refluxing 3-4 hour with formaldehyde solution, under the normal pressure temperature of reaction 40-70 ℃;

The methylation reaction feed liquid washes with water three times in the washing still, and static layering behind the branch vibration layer, is heated to 50-70 ℃, steams solvent and promptly gets d-alpha-tocopherol medicinal extract.

Above-mentioned organic solvent is benzene, toluene, normal hexane, methyl alcohol, ethanol, organic ether.

Compared with prior art, its technique effect and advantage:

1, adopt normal temperature and pressure to methylate and transform the mixed tocopherol isomer, processing condition require simple, implement suitability for industrialized production easily.

2, in the mixed tocopherol d-β, γ, methyltocol isomer to be converted into the d-alpha-tocopherol very complete, transformation efficiency is up to more than 99%, total tocopherol yield of reaction also reaches 90-92%, methylation reaction is highly stable.

3, this processing method technology is all applicable in the scope of total tocopherol content 40-95%, be not subjected to the influence of other non-tocopherol compositions in the mixed tocopherol, provide stable suitability for industrialized production technology for the mixed tocopherol isomer of various content is converted into the d-alpha-tocopherol.

Embodiment:

1, get mixed tocopherol 2kg, total tocopherol content 72.8% is made solvent with normal hexane, adds 6kg; Drop into catalyzer tin protochloride 1.6kg, do methylating agent stirring and refluxing reaction 4 hours, stopped reaction with 34% formaldehyde solution, water is given a baby a bath on the third day after its birth time, and branch vibration layer post-heating to 70 ℃ steams solvent, get methylate d-alpha-tocopherol 2.07kg, content 64.2%, yield 91%.

2, get mixed tocopherol 3kg, total tocopherol content 77.8% is made solvent with Virahol, adds 7kg; Dropping into concentration is 31% hydrochloric acid 7kg and catalyzer tin protochloride 1kg, zinc powder 1kg, do methylating agent stirring and refluxing reaction 3.5 hours with Paraformaldehyde 96, water is given a baby a bath on the third day after its birth inferior behind the stopped reaction, branch vibration layer post-heating to 60 ℃ steams solvent, get methylate d-alpha-tocopherol 2.9kg, content 72.8%, yield 90%.

Claims (1)

1, the preparation method of d-alpha-tocopherol comprises methylation reaction and washing, separating step, it is characterized in that its processing condition:

Mixed tocopherol is in 1: the ratio of 2-5 is dissolved among the organic solvent, and dissolving back is by the ratio input catalyzer tin protochloride of mixed tocopherol 1: 0.8 or 0.33; Do methylating agent in reactor stirring and refluxing 3-4 hour with formaldehyde solution, under the normal pressure temperature of reaction 40-70 ℃;

The methylation reaction feed liquid washes with water three times in the washing still, and static layering behind the branch vibration layer, is heated to 50-70 ℃, steams solvent and promptly gets d-alpha-tocopherol medicinal extract.