DD274626A1 - PROCESS FOR THE PREPARATION OF ORGANOSILYL PHOSPHANS - Google Patents

Abstract

The invention relates to a process for the preparation of organosilylphosphines which are of interest as synthesis building blocks for novel organophosphorus compounds. The aim of the invention is to develop a process for the preparation of these substances, which allows the direct silylation of phosphines under mild conditions and in short reaction times. The process for the preparation of organosilylphosphines of the general formula R1PHn (SiR2 3) 2-n, in which R1 can be alkyl, aryl, Me3Si, H and R2alkyl and n0,1, is characterized in that phosphines with trifluoromethanesulfonic acid silyl esters with addition of a tertiary amine in an inert solvent.

Description

Ausführungsbelspiele

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

example 1

Tris (uimethylsilyl) phosphine: A gas stream of PH ₃ is added to saturation through a solution of 0.1 mol Me ₃ SiOSO ₂ CF ₃ and 0.1 mol NCt ₃ in 200 m! Tüier headed. The end point of the reaction is reached when the ammonium salt has precipitated quantitatively as a red-brown oil. Another 0.3 mol of silylating agent is added to the reaction mixture. The ammonium is separated off, the solvent is removed in vacuo and the residue is fractionated. Bp: 115 ° C / 15 torr; Yield: 90%; NMR data: 6 ³¹ P: -254.3 ppm; 6 ²⁹ Si: +2.6 ppm (C ₆ D ₆ )

Example 2

Bis (trimethylsilyl) phosphine: The reaction solution of the reaction of PH ₃ with Me ₃ SiOSO ₂ CF ₃ / NEt ₃ (Example 1) is mixed with O.OJmo!

V / asser in 1OmITHF added. After separation of the ammonium salt and removal of the solvent is fractionated in vacuo. Bp: 60 ° C / 20 torr; Yield: 82%; NMR data: 6 ³¹ P: -237.4 ppm; 6 ²⁹ Si +3.5 ppm (C ₆ D ₆ )

Example 3

tert-Butyltrimethylsilylphosphan: 0.05 mol tert-butylphosphane are placed in 200 ml of Fihor. At ⁰ ° C., 0.05 mol of Me ₃ SiOSO ₂ ZNEt ₃ in 50 ml of ether are added dropwise within 10 minutes. The ammonium.silver precipitates quantitatively and is separated off.

It is then fractionally distilled.

Bp: 132 ^° C; Yield: 77%; 6 ³¹ P: -87.6 ppm (C ₆ D ₆ )

Example 4

Phenylbis (trimethylsilyl) phosphine: 0, OG mol Phenylphosphan we / den at Rai'.nemperatur in 150 ml of ether. Within 30 minutes, 0.1 mol of Me ₃ Si0r0 ₂ CF ₃ / NEt _{3 are} added dropwise in 100 ml of ether. The quantitatively precipitated Ammor.iumsalz is separated. After removal of the solvent, the mixture is fractionated in vacuo.

Bp: 91 ° C / 0.1 torr; Yield: 89%; 6 ³¹ P: -138.2 ppm (C ₆ D ₆ )

Claims (2)

Process for the preparation of organosilylphosphines of the general formula R ¹ PH _n (SiR ² ^ _n , in which R ¹ = alkyl, aryl, Me ₃ Si, H and R ² = alkyl and η = 0.1, daduich characterized in that phosphines with Trifluoromethansulfonsylylestern un: he addition of a tertiary amine in an inert solvent ¹ , preferably ether , to be reacted at low temperatures. Applicant goblet of the invention The invention relates to a method for Heistellung Organosilylphosphanen, which are of interest as synthetic building blocks for novel Orgnnophosphorverbindungen. Characteristic of the known technical solutions All known processes for the preparation of Organosilylphosphanen lead via metal parts species. Either alkali phosphides are reacted with chlorosilanes (G.Becker, O. Mundt, M. Roesslor and E. Schneider, Z. Anorg. Allg. Chem. 443 [1968] 42) or organosilylmagnesium compounds with chlorophosphanes in HMPA (H. Schumann and L Rösch, J. Organomet Chem 5511973] 257). The known processes are characterized by complex techniques or by very long reaction times. Object of the invention The aim of the invention is to develop a process for the preparation of organosilylphosphines which, in a one-pot reaction, allows the direct silylation of phosphines under mild reaction conditions with short reaction times. Explanation of the essence of the invention The invention is based on the object of developing a process which makes it possible to obtain organosilylphosphanes from readily available phosphanes in a smooth reaction. According to the invention, phosphine with Trifluormethansulfonsäuretrialkylsilylestern with the addition of a tertiary amine according to Eq. (1) implemented. This produces a mixture of approximately equal parts of tris (trialkylsily!) Phosphane and 6is (trialkylsilyl) phosphine. 2PH ₃ + 5R, SiOSO ₂ CF ₃ / NEt ₃ -> (R ₃ Si) ₃ P + (R ₃ Si) ₂ PH + 5HNEt ₃ ⁺ OSO ₂ CF ₃ - (1) R = alkyl If the mixture is mixed with an excess of the silylating agent, the tris-trialkylsilylphosphane is obtained in 90% yield. If, however, the mixture is mixed with the stoichiometric amount of water, then the proportion of tris (trialkylsilyl) phosphine according to Eq. (2) hydrolyzed to bis (trialkylsilyl) phosphine, which are isolated in 82% yield 2 (R ₃ Si) ₃ + H ₂ O -> (R ₃ Si) ₂ O + 2 (R ₃ Si) ₂ PH (2) R = alkyl In an analogous manner, in the reaction of primary phosphines with trialkylsilyl esters of trifluoromethanesulfonic acid and triethylamine, according to the stoichiometric ratios, organo-bis (trialkylsilyl) phosphanes according to Eq. (') and Organotrialkylsilylphosphane according to Eq. (4) received. R ¹ PH ₂ + 2RjSiOSO ₂ CF ₃ / NEt ₃ -> R ¹ P (SiRj) ₂ + 2HNEt ₃ ⁺ OSO ₂ CF ₃ - (3) R ¹ PH ₂ + R ₃ ^J SiOSO ₂ CF ₃ / NEt ₃ -> R ¹ PH (SiRl) + HNEt ₃ ⁺ OSO ₂ CF ₃ - (4) R ¹ = alkyl, aryl
R '= Alky! All reactions are carried out in an inert solvent, preferably ether, at ⁰ ° C. The reaction times are between 10 and 30 minutes. The yields are in all cases over 75%.