Preparation method of tris(trimethylsilyl)phosphite

Abstract

The invention discloses a preparation method of tris(trimethylsilyl)phosphate; through selection of an alkane or ether solvent, two reactants of an alkali metal silicon alkoxide and phosphorus halide are added to the above solvent in accordance with the molar ratio of 1:1, and vigorous stirring is carried out in the process of adding; and finally an inorganic salt is filtered to remove, and the solution is subjected to reduced pressure distillation under the condition of 90 DEG C / 20 mmHg to obtain the target product, wherein the purity of the product can reach more than 99.6%. Industrialized production is achieved, and the preparation method has huge market prospects and economic values.

Description

technical field [0001] The invention relates to a method for preparing high-purity tris(trimethylsilyl)phosphite. Background technique [0002] Tris(trimethylsilyl)phosphite is a commonly used pharmaceutical intermediate and organic reagent, mainly used in the synthesis of special alkenes or alkynes. At present, there is no mass-scale industrial production method in China, and it mainly relies on imports. The bulk import price of reagent-grade products is about 30,000 yuan / kg, while the maximum package price in the retail market is about 10,000 yuan / 100g. [0003] From the published reports, the only synthetic preparation method at present is the preparation method of using trimethylchlorosilane and phosphorous acid reaction in the presence of triethylamine and common solvents (such as tetrahydrofuran, cyclohexane, etc.). The reaction mechanism is with reference to the following reaction equation: wherein, triethylamine plays the role of absorbing the hydrogen chloride rel...

AI Technical Summary

Problems solved by technology

In summary, the existing technology has the following disadvantages: the reaction speed is slow, and the selectivity of the target product (1) can only reach 70% after reflux for 20 hours; the reaction process is controlled by equilibrium, and the by-product (2) in the system cannot be completely converted into the target product (1); in the subsequent product separation and purification process, the recovery of the by-product (2) needs to be considered; only relying on filtration cannot completely remove triethylamine hydrochloride, so in the subsequent product separation process, the volatile The strong triethylamine hydrochloride makes it difficult to realize industrialized continuous production; the difference between the boiling points of the two during the vacuum distillation process is not large (under a vacuum of 20mmHg, the boiling point difference is less than 20°C), and the by-product (2) has the same effect on the target product (1 ) purification caused some interference; the highest purity of products on the market is 98%, and there are no high-purity products above 99%

Not suitable for more demanding applications