DD251134A1 - PROCESS FOR PREPARING ORGANOSILYLMETHYLPHOSPHINIC ACID ESTERS - Google Patents

Abstract

The invention relates to a process for preparing organosilylmethylphosphinic acid esters of interest as intermediates for the synthesis of biocidally active compounds. The aim of the invention is to develop a process for the preparation of these substances, which does not require complex technologies and is characterized by short reaction times and low reaction temperatures. The process for preparing the organosilymethylphosphinic acid esters of the general formula R 1 3CR 2 2P (O) (OR 3), wherein R 1 alkyl, R 2 alkyl, halogen, H 4R and R 3 R 4 alkyl, may be aryl, is characterized in that methylphosphinic acid esters with trifluoromethanesulfonic acid silyl esters with the addition of a tertiary amine in an inert Be implemented solvents.

Description

(CH ₃ ) ₂ P (0) (OR ¹ ) + 2 R 1 SiOSO ₂ CF ₃ + 2 NEt ₃

0 ° C

(R ₃ Si-CH ₂ ) ₂ P (0) (0R ¹ ) + 2 (Et ₃ NH) ⁺ (OSO ₂ CF ₃ ) ¹

R ¹ = alkyl, aryl R ² = alkyl

embodiments

In the following the invention will be explained in more detail by means of examples:

example 1

(Trimethylsilylmethyl) phenylphosphinsäuremethylester:

10 g (0.058 mol) of PhMeP (O) (OMe) and 6.1 g (0.06 mol) of NEt ₃ are initially charged in 150 ml of ether. 13.3 g (0.06 mol) Me3SiOSO2CF ₃ dissolved in 50 ml of ether are added dropwise with stirring at ⁰ ° C. within 30 minutes. Then it is stirred for 3 hours at room temperature. The ammonium salt of trifluoromethanesulfonic acid precipitates as a yellow-brown oil. After separation of the salt, the solvent is removed in vacuo and the residue is fractionated.

Bp: 127 ° C / 0.2 Torr. Yield: 56%

Example 2

(TrimethylsilyldichlormethyOmethylphosphinsäuremethylester:

8 g (0.045 mol) of (CI ₂ CH) MeP (O) (OMe) and 5.1 g (0.05 mol) of NEt ₃ are initially charged in 150 ml of ether. At 0 ⁰ C is added dropwise 11.1 g (0.05 mol) of Me ₃ SiOSO ₂ CF _3, dissolved in 50 ml of ether to. The mixture is stirred for 2 hours at room temperature, the ammonium salt is separated off and fractionated in vacuo.

Bp: 144-146 ° C / 0.3 Torr Yield: 61%

Example 3

(Trimethylsilylmethyl) methylphosphinsäurephenylester:

8 g (0.047 mol) of Me ₂ P (O) (OPh) and 5.1 g (0.05 mol) of NEt ₃ are initially charged in 150 ml of ether. At ⁰ ° C., 11.1 g (0.05 mol) of Me ₃ SiOSO ₂ CF ₃ μmol of ether are added dropwise. The mixture is then stirred for 4 hours at room temperature. After separation of the ammonium salt, the residue is fractionated in vacuo.

Bp: 118 ° C / 0.1 Torr. Yield: 63%

Example 4

To (! Trimethylsi ylmethyl) phosphinate:

5 g (0.046 mol) of Me ₂ P (O) (OMe) and 12.1 g (0.12 mol) of NEt ₃ are initially charged in 150 ml of ether. With stirring is added dropwise in 50 ml of ether at 0 ⁰ C 26.6 g (0.12 mol) of Me ₃ SiOSO ₂ CF _3. The reaction mixture is stirred at reflux for 15 hours. After separation of the ammonium salt, the solvent is distilled off and the residue is fractionated in vacuo.

Bp: 133-135 ° C: 0.5 torr yield: 16%

Claims (1)

Process for the preparation of Organosilylmethylphosphinsäureestern of the general formula R 1 Si-CR ² -P (0) (0R ³ ), in which R ¹ = alkyl, R ² = alkyl, halogen, H and R ³ = R ⁴ = alkyl, aryl, characterized in that Methylphosphinsäureester with Trifluormethansulfonsäuresilylestern with addition of a tertiary amine in an inert solvent, preferably ether, at low Temperatures are implemented. Field of application of the invention The invention relates to a process for the preparation of organosilylmethylphosphinic esters which are of interest as intermediates for the synthesis of biocidally active compounds. Characteristic of the known technical solutions Silylmethylphosphinsäureester have been known for some time. They were obtained by reaction of chloromethylsilanes with phosphonic acid esters (E.A. Chernyshev, E.F. Bugerenko, N.A. Nikolaeva and A.D. Petrov, Dokl. Akad. Nauk SSSR, 147 Some free silylmethylphosphinic acids were obtained by reaction of silylmethylmagnesium chlorides with POCl _{3 followed} by hydrolysis (AE Canavan and C. Eaborn, J. Chem. Soc. 1959, 3751). * All reactions described are characterized by long reaction times and in part by high reaction temperatures. Object of the invention The aim of the invention is to develop a process for the preparation of Triorganosilylmethylphosphinsäureestern, which requires no complicated technologies and laborious reactions and is characterized by short reaction times and low reaction temperatures. Explanation of the essence of the invention The invention has for its object to develop a method that allows starting from easily accessible compounds to win the Organosilylmethylphosphinsäureester in a smooth reaction. According to the invention, methylphosphinic esters with trifluoromethanesulfonic acid triorganosilyl esters with the addition of a tertiary amine according to Eq. (1) reacted to triorganosilylmethylphosphinic. 1'Z 3 °°^C + RtOH-P (O) (OR ^) + 'NEt, J. ^Λ R ⁴ (D. R 1 Si-CR ₀ -P (O) (OR ³ ) + (Et ₇ NH) ⁺ COSO ₀ CF.,) " R ¹ = alkyl R ² = alkyl, halogen, H R ³ = R ⁴ = alkyl, aryl All reactions are carried out in an inert solvent, preferably ether, at ⁰ ° C. The reaction times are 2 to 4 hours, the yields 50-70%. The shortest reaction times and best yields are observed when the substituent R ^{2 has} an I effect. This is especially true for halogen substituents. If dimethylphosphinic acid ester is reacted with an excess of trifluoromethanesulfonylsilyl ester and amine, then a reaction time of 10-15 hours in a yield of up to 20% results in a double silylation according to Eq. (2) achieved.