CH433291A - Process for the production of phosphines - Google Patents

Description

  

  
 



  Process for the production of phosphines
Various processes for the production of organic derivatives of phosphorus are already known.



  However, these processes are too expensive and in some cases require the use of high pressure equipment. In many cases, the yields are also not sufficiently high. So z. B. the yield of triamylphosphine from one mole of PCl3 and three moles of ammonium sodium is only 22%.



   The present invention is now intended to enable an improved production of certain phosphines.



   The process according to the invention for the preparation of compounds of the formula PR'3 is characterized in that a compound of the formula (RO) 3P is reacted with a compound of the formula R'Na, where R is a hydrocarbon or halohydrocarbon radical and R 'is an aliphatic one or cycloaliphatic radical or an alkoxyphenyl radical.



   It is expedient to use at least 3 mol of the compound R'Na for each mol of the other reaction component. The compound R'Na can be used in excess, e.g. B. up to 10 moles, although a large excess is usually not necessary for good yields.



   The compounds obtainable by the process of the invention include the following:
Trimethylphosphine, tripropylphosphine, tributylphosphine, tri-sec.-butylphosphine, tri-tert.-butylphosphine, triisobutylphosphine, propyldibutylphosphine, triamylphosphine, trioctylphosphine, triisooctylphosphine, trisooctylphosphine, tris-decylphosphine, trisooctylphosphine, tris-decylphosphine, trisooctylphosphine, tris-decylphosphine, trisooctylphosphine, tris-decylphosphine, trisooctylphosphine, tris-decyladyclophosphine, tris-decicyclophosphine, tris-decyladyclophosphine, tris-decicyclophosphine, tris-decyladyclophosphine, tris-decyladyclophosphine, tris-decyladyclophosphine, tri-tert. Tris (p-ethoxyphenyl) phosphine.



   The following substances can be used as compounds of the formula (RO) 5P:
Trimethyl phosphite, triethyl phosphite, tributyl phosphite, tri- (2-chloroethyl) phosphite, tri- (4-chlorobutyl) phosphite, trioctyl phosphite, trisdecyl phosphite, triphenyl phosphite, tri (p-methylphenyl) phosphite, tri-0-chlorophenyl phosphite, tri-o-chlorophenyl phosphite - p - bromophenyl phosphite, tri- (mmethylphenyl) phosphite, tri-sec. - butyl phosphite, tribenzyl phosphite.



   As a compound of the formula R'Na, for. B. one of the following substances can be used:
Methyl sodium, ethyl sodium, propyl sodium, isopropyl sodium, butyl sodium, sec-butyl sodium, tert. Butyl Sodium, Isobutyl Sodium, Amyl Sodium, Hexyl Sodium, Cyclohexyl Sodium, Cyclopentyl Sodium, Benzyl Sodium, Octyl Sodium, Decyl Sodium, Isooctyl Sodium, Octadecyl Sodium, p-Methoxyphenyl Sodium, o-Ethoxyphenyl Sodium.



   The organosodium compound can be formed beforehand or in situ, from metallic sodium and a corresponding halogenated hydrocarbon or the like. B. from l-chlorobutane, l-bromobutane, 2-chlorobutane, l-bromo-2-methylpropane, 2-bromoethylpropane, l-chloropentane, 1-chlorooctane, l-bromoanisole.



   Inert solvents can be used, including hydrocarbons, such as solvent naphtha, hexane, toluene, benzene, octane.



   The reaction can be carried out at normal pressure, elevated pressure or reduced pressure. The reaction is often exothermic, and cooling can be carried out from the outside.



   In the following examples, all parts and percentages are based on weight, unless stated otherwise.



   example 1
In a 12 liter flask, 676 grams of sodium (29.4 moles) and 400 grams of solvent naphtha were heated to 110 under a nitrogen atmosphere until the sodium had melted. The mixture was stirred vigorously using a disperser to break up the sodium into microscopic particles less than 100 microns in diameter. After cooling to 30 ° C, a solution of 1415 g (4.55 moles) triphenyl phosphite in 1395 g (15.05 moles) 1-chlorobutane was added over a period of two hours using a cooling bath, maintaining the temperature at 30 to 500 ° C has been. The reaction mixture was stirred for an additional two hours and then washed twice with 6 liters of water.

   The solvent was removed in vacuo, leaving 810 g (88% yield) of crude tributylphosphine.



  Fractional distillation gave 765 g of tributylphosphine in the form of a colorless liquid with a boiling point of 70-74 ° C. / 0.5 mm, nD25 1.4600.



   Example 2
The procedure of Example 1 was repeated, but using 4.55 moles of trimethyl phosphite instead of triphenyl phosphite. The yield of crude tributylphosphine was 94.70 / 0, b.p. 110 to 1250 ° C./8 mm.



   Example3
Trioctyl phosphite was prepared following the procedure of Example 1, but using 4.0 moles of sodium dispersed in 300 g of naphtha and diluted with 300 g of hexane. 0.6 mol of triphenylphosphite, which was dissolved in 1.8 mol of n-octyl chloride, was added to this mixture. The addition takes place over a period of 40 min at 40 to 60 ° C. The yield of crude trioctylphosphine was 191 g (88 / o), boiling point 190-210 ° C./1 mm, nD25 1.4683.



   Example 4
A solution of 0.040 mole of trimethylphosphate in 0.137 mole of o-bromoanisole was slowly added to 0.28 mole of sodium dispersed in 200 g of solvent naphtha. The addition takes place at 15-20 ° C. After two hours of stirring at 2040 ° C. and one hour at 800 ° C., the mixture was treated with 200 g of water. The tris (o-methoxyphenyl) phosphine thus produced was filtered off and at 80 ° in vacuo "C dried. 11.1 g (78.7% of theory) of a product with a melting point of 203 to 2050 ° C. (literature: 204 ° C.) are obtained. The product is a light yellow powder.

 

Claims (1)

PATENT CLAIM Process for the preparation of a compound of the formula PR'3, characterized in that a compound of the formula (RO) 3P is reacted with a compound of the formula R'Na, where R is a hydrocarbon or halogenated hydrocarbon radical and R 'is an aliphatic or cycloaliphatic radical or is an alkoxyphenyl radical. SUBCLAIMS 1. The method according to claim, characterized in that at least 3 moles of the compound R'Na are used for each mole of the compound (RO) 3P. 2. The method according to claim, characterized in that R is an alkyl radical. 3. The method according to claim, characterized in that R 'is an alkyl radical.