CN1031711C - Novel method for synthesizing 1-trimethylsilyl propine - Google Patents

Abstract

The invention relates to a new method for synthesizing 1-trimethylsilyl propine, belonging to a new process for synthesizing substituted unsaturated hydrocarbon, wherein acetylene is used as a raw material, active hydrogen atoms of the acetylene are selectively subjected to a Grignard reaction, then the 1-trimethylsilyl acetylene is obtained through a silylation reaction, and then the 1-trimethylsilyl propine is obtained from the acetylene through the Grignard reaction and a methylation reaction, wherein the hexamethylsiloxane content of the product is less than 350ppm, the purity is higher than 99.5 percent, and the purity requirement of preparing the high molecular weight 1-trimethylsilyl propine through a cation double decomposition catalytic polymerization reaction is met.

Description

The novel method of the synthetic silica-based propine of 1-front three

The novel method of the synthetic silica-based propine of 1-front three the invention belongs to the synthesis technique of the unsaturated hydrocarbons of replacement.

Silica-based propine (the Trimethylsilylpropyne of 1-front three, TMSP) boiling point 99-100 ℃/760 mmhg, be the poly-silica-based propine (Polytrimethylsilylpropyne of 1-front three of oxygen permeable membrane material of new generation, PTMSP) monomer, so far, the method for synthetic TMSP has two kinds substantially: the one, and alkynes lithium alkylation methods, the employing propine is a raw material, in hexane, obtain the propine that Li replaces, then with (CH with the reaction of tetrabutyl lithium ₃) ₃The SiCl reaction obtains the silica-based propine of 1-front three (K.Takada etc., J.Appl.Polym.Sci., 30,1605 (1985); T.Kinoshita etc., Polym.Preprints.JPn., 35,2170 (1985)); The 2nd, traditional Grignard, promptly propine Yu Geshi reagent react generates CH ₃C ≡ CMgBr, and then with (CH ₃) ₃SiCl (Me ₃SiCl) reaction generates the silica-based propine of 1-front three.The high density lithium alkylide is used in alkynes lithium alkylation methods reaction, and condition is very harsh, operational difficulty, valuable product and laboratory method sheerly, unsuitable scale production; But although and traditional Grignard macro preparation, in the building-up process by Me ₃Hexamethyl siloxanes (the M that reaction produces is paid in the SiCl hydrolysis ₂, boiling point 101 ℃/760 mmhg) existence make product TMSP can't be used for carrying out positively charged ion metathesis polyreaction and generate PTMSP gas film material, M ₂Boiling point and TMSP very approaching, common rectifying column is difficult to separate by product M ₂, usually introduce new impurity with the chemical method separation.

The objective of the invention is to adopt suitable operational path, cheap and produce expediently and contain M ₂Low and be fit to carry out the TMSP of positively charged ion metathesis catalytic polymerization.

The ingenious part of the operational path of the present invention's design just is the acetylene from cheapness, produce the silica-based acetylene (Trime-thylsilylacetylene of intermediate product front three earlier through grignard reaction and Silanization reaction, TMSA), its boiling point is 52 ℃/760 mmhg, therefore in this section reaction, even if generate M ₂Also by common post fractionation it is separated easily, the TMSA that gained is purer both can directly prepare functional polymer as monomer for catalyzed polymerization or copolymerization, in the present invention, can be that raw material prepares TMSP through grignard reaction and methylation reaction again with it again, the separation and purification of final product be reduced to TMSP and have separated with TMSA, because boiling point differs 48 ℃ between the two, can separate by common fractional column, thereby guaranteed very low M among the product TMSP ₂Content, unreacted TMSA can be recycled simultaneously.

The present invention has been owing to designed first synthetic mesophase product TMSA, and the operational path of resynthesis TMSP thereby it both be applicable to that the laboratory synthesized high-purity TMSP, can satisfy the processing requirement of the high-purity TMSP of scale production again.

The more detailed description of the present invention is: be raw material with acetylene, make the reaction of one of them reactive hydrogen atom selectively, synthesize the silica-based acetylene of front three, and then obtain can removing by product M through common post fractionation by grignard reaction and two steps of methylation reaction ₂(content is lower than 350ppm), purity are higher than the TMSP of 99.5wt%.

The present invention produces the signal formula of TMSP reaction such as following by acetylene: (1) (2) (3) (4) reaction (1) is to carry out in the saturated tetrahydrofuran (THF) of acetylene (THF), and 10-30 ℃ of temperature of reaction drip excessive slightly C on one side in the reaction process ₂H ₅The THF solution of MgBr (EtMgBr) Yi Bian feed gas acetylene, after dripping off, drips an amount of Me again ₃SiCl solution reacts (2), the reactant room temperature is placed and is spent the night, separate organic layer with electrolyte solution then, the cut that dried organic layer carries out post separated and collected 52 ℃/760 mmhg promptly gets intermediate product TMSA, containing in the anhydrous THF solution of EtMgBr, react (3) by the TSMA that drips equivalent, add stream after, drip excessive slightly (CH again ₃O) ₂SO ₂, the long-time backflow reacted (4), adds aqueous electrolyte liquid then and tells organic layer, and dry aftercut is got 99-100 ℃ of fractions and is high-purity TMSP, productive rate 60%.

By technology gained TMSP product of the present invention, warp ¹H-NMR, ¹³C-NMR and mass spectroscopy prove that its structure is formed consistent with the TMSP of standard.

Relatively see Table 1 by the purity of the TMSP of the inventive method preparation and polymerization and document

Table 1 TMSP purity and performance are relatively

Project	Literature method	The inventive method
			TMSP content (wt%)	95.922	99.780
M 2Content (wt%)	3.840	0.032
			Other foreign matter content	0.239	0.187
The polyreaction performance	Can not carry out	Reactivity worth is good
					Can make Mwt 〉=5 * 10 5PTMSP

Embodiments of the invention are as follows:

The preparation of the embodiment silica-based acetylene of 1 (1) 1-front three (TMSA):

In 300 milliliters of anhydrous THF solutions, feed acetylene under 20 ℃ to saturated, drips the THF solution of 0.63 mole EtMgBr, drip off the back and continue to lead to acetylene half an hour, drip 75 milliliters of Me then ₃SiCl (0.59 mole), 20 ℃ were reacted 10 hours down, and placement is spent the night, and adds aqueous electrolyte liquid then to tell organic layer, uses anhydrous Na ₂SO ₄Drying, fractionation gets TMSA, 52 ℃ of boiling points, productive rate 50%;

(2) preparation of TMSP:

In the anhydrous THF solution that contains 0.41 mole of EtMgBr, drip the TMSA of equivalent under 20 ℃, add the back and refluxed 1 hour, drip excessive slightly (CH ₃O) ₂SO ₂, refluxed again 10 hours, reclaim unreacted TMSA and reuse, add aqueous electrolyte liquid and tell organic layer, use anhydrous Na ₂SO ₄It is TMSP that dry aftercut is got 99-100 ℃ of fractions, productive rate 60%.

Embodiment 2, and reaction is all carried out under 15 ℃, and other is operated with embodiment 1.

Embodiment 3, and reaction is all carried out under 30 ℃, and other are operated with embodiment 1.

Embodiment 4, and reaction is all carried out under 10 ℃, and other are operated with embodiment 1.

Claims (1)

1, the method for the synthetic silica-based propine of 1-front three, the invention is characterized in acetylene to be raw material, earlier produce the silica-based acetylene of intermediate product 1-front three through grignard reaction and Silanization reaction, make the silica-based propine of 1-front three by the silica-based acetylene of 1-front three through grignard reaction and methylation reaction again, reaction follows these steps to carry out: (1) (2) (3) (4)