Preparation of organophosphorus compounds

Organophosphorus compounds are prepared by reacting an unsaturated compound, such as a striaght-chain, branched or cyclic olefin or a diene having conjugated or nonconjugated double bonds, with a phosphine by a process in which phosphine and/or phosphine-containing compounds are subjected to an addition reaction with the unsaturated compounds in the presence of a solid heterogeneous catalyst. Particularly suitable heterogeneous catalysts are zeolites and phosphates.

The present invention relates to a process for the preparation of 
organophosphorus compounds. 
A wide variety of possible methods exist for the synthesis of 
organophosphorus compounds. For example, triphenylphosphine can be 
prepared by subjecting benzene and diphenylchlorophosphine to a 
Friedel-Crafts reaction (JP 59/116 387). For the synthesis of 
alkylphosphines, in particular methylphosphines, white phosphorus can be 
reacted with tertiary and secondary amines (DE 2 730 742) or phosphine 
with a tertiary amine and an alkyl halide (DE 2 727 390 and DE 2 407 461) 
or white phosphorus can be reacted with an alkyl halide in the presence of 
HCl (DE 2 255 395), mixtures of primary, secondary and tertiary phosphines 
being obtained in moderate yields. The reaction of metal phosphides with 
alkyl halides (J. Org. Chem. 42 (1977), 3247-3251 or J. Inorg. Nucl. Chem. 
35 (8) (1973), 2659) or water (Inorg. Synthn. 16 (1976), 161-163), as well 
as the reaction of tetraalkyldiphosphine sulfides with LiAlH.sub.4 (eg. 
Chem. Ber. 95 (1962), 64) or with tributylphosphine (Inorg. Synth. 21 
(1982 ), 180-181), makes it possible to prepare various organophosphorus 
compounds. The Michaelis-Arbuzow rearrangement reaction (eg. Inorg. Nucl. 
Chem. 31 (1969), 3684) can be used for the preparation of primary 
phosphines, mainly methylphosphine. Furthermore, the Grignard reaction of 
triphenyl phosphites leads to alkylphosphines (Syn. Reactiv. Inorg. 
Metal-Org. Chem. 4 (2) (1974), (149). 
The disadvantages of these known preparation processes are that the desired 
compound or a mixture of compounds which is difficult to separate is 
usually obtained over a plurality of reaction steps. The use of white 
phosphorus as a starting material presents problems with regard to 
handling, as does the use of metal phosphites, which are not cheaply 
available. Furthermore, phosphines having mixed substituents are very 
difficult to synthesize by the conventional processes. 
It is also known that alkylphosphines can be prepared from PH.sub.3 and 
aliphatic monoolefins in the presence of peroxides as free radical formers 
(German Patent 899,040 and U.S. Patent 2,957,931) or under UV irradiation 
(J. Chem. Soc. (1963), 1083). These processes are only of limited use in 
the preparation of alkylphosphines and, when they can be used, give only 
moderate yields. 
It is an object of the present invention to synthesize organophosphorus 
compounds in high yields from cheap starting materials by a simple 
synthesis which takes place in one reaction step. It was also intended to 
find a simple possible synthesis for organophosphorus compounds having 
mixed substituents. 
We have found that this object is achieved by a process for the preparation 
of organophosphorus compounds by reacting an unsaturated compound, such as 
a straight-chain, branched or cyclic olefin or a diene having conjugated 
or nonconjugated double bonds with a phosphine by a process in which 
phosphine and/or a phosphine-containing compound is subjected to an 
addition reaction with the unsaturated compound in the presence of a solid 
heterogeneous catalyst. 
In the novel process, the requirements set at the outset for the reaction 
are met. In view of the prior art, the success of the process was 
particularly surprising since, because of the sensitivity of the 
phosphorus compounds used and those obtained to oxygen, temperature, etc., 
the reaction was not expected to take place readily and was certainly not 
expected to give such high conversions and selectivities. Furthermore, the 
novel process is very suitable for the synthesis of organophosphorus 
compounds having mixed substituents. The requirements which the catalysts 
used have to meet, such as catalyst life, time-on-stream, mechanical 
stability, activity and selectivity, are very readily met. This is all the 
more surprising since the highly sensitive phosphines used were expected 
to react with the catalyst. 
The unsaturated compounds used are straightchain, branched or cyclic 
olefins and dienes having conjugated and nonconjugated double bonds. 
Suitable olefins are isobutylene, propylene, ethylene, n-butene, cis- and 
trans-but-2-ene, pentenes, methylbutenes, hexenes, methylpentenes, 
ethylbutenes, cyclopentenes and cyclohexenes, and suitable dienes are 
isoprene, vinylcyclohexene, hexadienes and pentadienes. 
Suitable phosphine-containing compounds are primary and secondary 
phosphines, diphosphanes, polyphosphanes and organophosphorus oxides. 
Suitable primary phosphines are compounds of the formula H.sub.2 PR, where 
R is straight-chain or branched alkyl of 1 to 16 carbon atoms, eg. methyl, 
ethyl, propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl, hexyl, 
decyl and dodecyl, or cyclic alkyl radicals of 3 to 8 carbon atoms, eg. 
pentyl, hexyl or heptyl, or aryl or aralkyl or alkylaryl, which in turn 
may be substituted in the aromatic nucleus by substituents which are inert 
under the chosen reaction conditions, eg. phenyl, benzyl, phenylethyl, 
mesityl, toluyl, xyloyl, ethylphenyl, propylphenyl or phenylpropyl, or 
silyl radicals, eg. trimethylsilyl, triethylsilyl, dimethylphenylsilyl, 
dimethylethylsilyl or dimethylpropylsilyl, or amine radicals, eg. 
dimethylamine, diethylamine, methylethylamine, methylpropylamine or 
methylphenylamine radicals, or boryl radicals, eg. dimethylboryl, 
diethylboryl, methylpropylboryl or methylphenylboryl. 
Suitable secondary phosphanes are compounds of the formula HPRR.sup.1, 
where R and R.sup.1 can be identical or different and may have the above 
meanings. 
Suitable diphosphanes are compounds of the formula RR.sup.1 P-PR.sup.1 R, 
where one or more radicals are hydrogen and the remaining radicals R and 
R.sup.1 may be identical or different and may have the above meadings. 
However, compounds which have 2-phosphino radicals and also possess a 
straight-chain or branched carbon chain between these radicals are also 
suitable. 
Linear and cyclic polyphosphines, eg. triphosphines of the formula RR.sup.1 
P-PR-PR.sup.11 R, where one or more radicals are hydrogen and the 
remaining radicals may have the above meanings, are suitable starting 
materials. A straight-chain or branched carbon chain may furthermore be 
present between the individual phosphino radicals. 
Compounds of the formula RR.sup.1 R.sup.2 P(0) can be reacted as 
organophosphorus oxides in the process, and one or more of the radicals 
are hydrogen and the remaining radicals R, R.sup.1 or R.sup.2 may be 
identical or different and may have the above meanings. 
The unsaturated compounds used are straightchain or branched olefins of 1 
to 16 carbon atoms, eg. ethylene, propylene, n-butene, 
cis/trans-but-2-ene, isobutene, pentenes, methylbutenes, hexenes, 
methylpentenes, ethylbutenes, ethyloctenes, dodecenes, phenylpropene, 
styrene, ethylstyrene and isobutenylbenzene, and cyclic olefins, eg. 
cyclopentenes or cyclohexenes, and di- and polyenes having conjugated 
double bonds, eg. isoprene, vinylcyclohexene, hexadienes, pentadienes and 
butadienes. 
The reactions according to equations 1 and 2 illustrate the invention 
##STR1## 
The heterogeneous catalysts used in the novel process are preferably 
zeolite catalysts in acidic form. Zeolites are crystalline 
aluminosiltcates which have a highly ordered structure with a rigid 
three-dimensional network of SiO.sub.4 and AlO.sub.4 tetrahedra which are 
bonded by common oxygen atoms. The ratio of the Si and Al atoms to oxygen 
is 1 : 2 (cf. Ullmanns Encyclopadie d. techn. Chemie, 4th Edition, Volume 
24, page 575 (1983)). The electrovalency of the aluminum-containing 
tetrahedra is balanced by the inclusion of cations in the crystal, for 
example an alkali metal or hydrogen ion. Cation exchange is possible. The 
voids between the tetrahedra are occupied by water molecules prior to 
dehydration by drying or calcination. 
In the zeolites, other elements, such as B, Ga, Fe, Cr, V, As, Sb, Bi or 
Be, or mixtures of these may be incorporated, instead of aluminum, in the 
framework, or the silicon can be replaced by a tetravalent element, such 
as Ge, Ti, Zr or Hf. 
Zeolites are divided into various groups, depending on their structure (cf. 
Ullmanns Encyclopadiae d. techn. Chemie, 4th Edition, Vol. 24, page 575 
(1983)). For example, chains of tetrahedra form the zeolite structure in 
the mordenite group and sheets of tetrahedra form the zeolite structure in 
the chabasite group, whereas in the faujasite group the tetrahedra are 
arranged to form polyhedra, for example in the form of a cubooctahedron, 
which is composed of 4-membered rings and 6-membered rings. Depending on 
the bonding of the cubooctahedra, which results in cavities and pores of 
different sizes, a distinction is made between zeolites of type A, L, X 
and Y. 
Suitable catalysts for the novel process are zeolites from the mordenite 
group, the fine-pore zeolites of the erionite and chabasite type and 
zeolites of the faujasite type, for example Y, X or L zeolites. This group 
of zeolites also includes the ultrastable zeolites of the faujasite type, 
ie. dealuminated zeolites. Processes for the preparation of such zeolites 
are described in Catalysis by Zeolites, Volume 5, from Studies in Surface 
Science and Catalysis, ed. B. Imelik et al., Elsevier Scientific 
Publishing Company 1980, page 203, and Crystal Structures of Ultra-stable 
Faujasites, Advances in Chemistry Series No. 101, American Chemical 
Society Washington DC, page 226 et seq (1971) and in U.S. Patent 
4,512,961. 
Zeolites of the pentasil type are particularly advantageous. They have a 
5-membered ring consisting of SiO.sub.4 tetrahedra as a common building 
block. They possess a high SiO.sub.2 /Al.sub.2 O.sub.3 ratio and pore 
sizes which are between those of the zeolites of type X and Y (cf. 
Ullmanns Encyclopadie d. techn. Chem., 4th Edition, Vol. 24, 1983). 
These zeolites may have different chemical compositions. They are 
aluminosilicate, borosilicate, iron silicate, beryllium silicate, gallium 
silicate, chromium silicate, arsenosilicate, antimony silicate and bismuth 
silicate zeolites or mixtures of these, and aluminogermanate, 
borogermanate, gallium germanate and iron germanate zeolites or mixtures 
of these. The aluminosilicate, borosilicate and iron silicate zeolites of 
the pentasil type are particularly suitable for the novel process. The 
aluminosilicate zeolite is prepared, for example, from an aluminum 
compound, preferably Al(OH).sub.3 or Al.sub.2 (SO.sub.4).sub.3, and a 
silicon component, preferably finely divided silica, in aqueous amine 
solution, in particular in polyamines, such as 1,6-hexanediamine or 
1,3-propanediamine or triethylenetetramine solution, with or, in 
particular, without the addition of an alkali or alkaline earth, at from 
100 to 220.degree. C. under autogenous pressure. They also include the 
isotactic zeolites according to European Pat. No. 34,727 and 46,504. The 
aluminosilicate zeolites obtained have an SiO.sub.2 /Al.sub.2 O.sub.3 
ratio of from 10 to 40,000, depending on the amounts of starting materials 
chosen. Aluminosilicate zeolites of this type can also be synthesized in 
an ether medium, such as diethylene glycol dimethyl ether, in an alcoholic 
medium, such as methanol or butane-1,4-diol, or in water. 
Borosilicate zeolites can be synthesized, for example, at from 90.degree. 
to 200.degree. C. under autogenous pressure by reacting a boron compound, 
eg. H.sub.3 BO.sub.3, with a silicon compound, preferably finely divided 
silica, in aqueous amine solution, in particular in 1,6-hexanediamine or 
1,3-propanediamine or triethylenetetramine solution, with or, in 
particular, without the addition of an alkali or alkaline earth. They 
include the isotactic zeolites according to European Pat. Nos. 34,727 and 
46,504. Such borosilicate zeolites can also be prepared if the reaction is 
carried out in ether solution, eg. diethylene glycol dimethyl ether, or in 
alcoholic solution, eg. hexane-1,6-diol, instead of in aqueous amine 
solution. 
The iron silicate zeolite is obtained, for example, from an iron compound, 
preferably Fe.sub.2 (SO.sub.4).sub.3, and a silicon compound, preferably 
finely divided silica, in aqueous amine solution, in particular 
1,6-hexanediamine, with or without the addition of an alkali or alkaline 
earth, at from 100.degree. to 220.degree. C. under autogenous pressure. 
The silicon-rich zeolites (SiO.sub.2 /Al.sub.2 O.sub.3 .gtoreq.10) which 
can be used also include zeolites of the ZSM type, ferrierite, Nu.sup.-1 
and Silicalit.RTM.. 
The aluminosilicate, borosilicate and iron silicate zeolites thus prepared 
can be isolated, dried at from 100.degree. to 160.degree. C., preferably 
110.degree. C., and calcined at from 450.degree. to 550.degree. C. and 
then molded with a binder in a weight ratio of from 90:10 to 40:60 to give 
extrudates or pellets. Suitable binders are various aluminas, preferably 
boehmite, amorphous aluminosilicates having an SiO.sub.2 /Al.sub.2 O.sub.3 
ratio of from 25:75 to 90:5, preferably 75:25, silica, preferably finely 
divided SiO.sub.2, mixtures of finely divided SiO.sub.2 and finely divided 
Al.sub.2 O.sub.3, TiO.sub.2, ZrO.sub.2 and clay. After the molding 
procedure, the extrudates or pellets are dried at 110.degree. C. for 16 
hours and calcined at 500.degree. C. for 16 hours. 
Very efficient catalysts are also obtained if the aluminosilicate or 
borosilicate zeolite isolated is molded directly after drying and is not 
subjected to calcination until after the molding procedure. The 
aluminosilicate and borosilicate zeolites prepared can be used in pure 
form, without a binder, as extrudates or tablets, examples of suitable 
extrusion or peptizing assistants being ethylcellulose, stearic acid, 
potato starch, formic acid, oxalic acid, acetic acid, nitric acid, 
ammonia, amines, silicoesters and graphite or mixtures of these. 
If, because of its method of preparation, the zeolite is not in the 
catalytically active, acidic H form but, for example, in the Na form, the 
latter can be completely or partially converted into the desired H form by 
ion exchange, for example with ammonium ions, and subsequent calcination, 
or by treatment with acids. 
If, when the zeolite catalysts are used according to the invention, 
deactivation occurs as a result of coking, it is advisable to regenerate 
the zeolites by burning off the coke deposit with air or with an 
air/N.sub.2 mixture at from 400 to 550.degree. C., preferably 500.degree. 
C. As a result, the zeolites regain their initial activity. 
By precoking, it is possible to adjust the activity of the catalyst to 
obtain optimum selectivity with respect to the desired reaction product. 
In order to obtain very high selectivity, high conversion and a long 
catalyst life, it is advantageous to modify the zeolites. In a suitable 
method of modification, for example, the unmolded or molded zeolites are 
doped with metal salts by ion exchange or by impregnation. The metals used 
are alkali metals, such as Li, Cs or K, alkaline earth metals, such as Mg, 
Ca or Sr, metals of main groups 3, 4 and 5, such as Al, Ga, Ge, Sn, Pb or 
Bi, transition metals of subgroups 4 to 8, such as Ti, Zr, V, Nb, Cr, Mo, 
W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd or Pt, transition metals of 
subgroups 1 and 2, such as Cu, Ag or Zn, and rare earth metals, such as 
La, Ce, Pr, Nd, Er, Yb and U. 
The doping is advantageously carried out by a procedure in which, for 
example, the molded zeolite is initially taken in a riser tube and an 
aqueous or ammoniacal solution of a halide or of a nitrate of the metals 
described above is passed over the said zeolite at from 20.degree. to 
100.degree. C. Ion exchange of this type may be carried out, for example, 
on the hydrogen, ammonium and alkali metal form of the zeolite. In another 
possible method for applying the metals to the zeolites, the zeolite 
material is impregnated with, for example, a halide, a nitrate or an oxide 
of the metals described above, in aqueous, alcoholic or ammoniacal 
solution. Both ion exchange and impregnation may be followed by one or 
more drying steps and, if desired, repeated calcination. 
In a possible embodiment, for example, Cu(NO.sub.3).sub.2. 3H.sub.2 O or 
Ni(NO.sub.3).sub.2. 6H.sub.2 O or Ce(NO.sub.3)3 . 6H.sub.2 O or LaNO.sub.3 
.sub.2. 6H.sub.2 O or Cs.sub.2 CO.sub.3 is dissolved in water and this 
solution is used to impregnate the molded or unmolded zeolite for a 
certain time (about 30 minutes). Any supernatant solution is freed from 
water in a rotary evaporator. Thereafter, the impregnated zeolite is dried 
at about 150.degree. C. and calcined at about 550.degree. C. This 
impregnation process can be carried out several times in succession in 
order to obtain the desired metal content. 
It is also possible, for example, to prepare an aqueous Ni(CO.sub.3).sub.2 
solution or ammoniacal Pd(NO.sub.3).sub.2 solution and to suspend the pure 
zeolite powder therein at from 40.degree. to 100.degree. C. for about 24 
hours, while stirring. After the product has been filtered off, dried at 
about 150.degree. C. and calcined at about 500.degree. C., the zeolite 
material thus obtained can be further processed with or without a binder 
to give extrudates, pellets or fluidizable material. 
The zeolite in the H form or ammonium form or alkali metal form can be 
subjected to ion exchange by a method in which the zeolite, in the form of 
extrudates or pellets, is initially taken in a column and, for example, an 
aqueous Ni(NO.sub.3).sub.2 solution or ammoniacal Pd(NO.sub.3).sub.2 
solution is circulated over the said zeolite at slightly elevated 
temperatures of from 30.degree. to 80.degree. C. for from 15 to 20 hours. 
Thereafter, the product is washed thoroughly with water, dried at about 
150.degree. C. and calcined at about 550.degree. C. In the case of some 
metal-doped zeolites, for example Pd-, Cu- or Ni-doped zeolites, an 
aftertreatment with hydrogen is advantageous. 
In another possible method of modification, the molded or unmolded zeolite 
is subjected to a treatment with acids, such as hydrochloric acid, 
hydrofluoric acid and phosphoric acid and/or steam. In this procedure, a 
zeolite in powder form is advantageously treated with 1 N phosphoric acid 
for 1 hour at 80.degree. C. After the treatment, the product is washed 
with water, dried at 110.degree. C. for 16 hours and calcined at 
500.degree. C. for 20 hours. In another procedure, the zeolite, before or 
after it has been molded with a binder, is treated with a 3-25% strength 
by weight aqueous hydrochloric acid for from 1 to 3 hours at from 
60.degree. to 80.degree. C. The zeolite treated in this manner is then 
washed with water, dried, and calcined at from 400.degree. to 500.degree. 
C. 
In a particular embodiment of the acid treatment, the zeolite material, 
before it has been molded, is treated at elevated temperatures with 
hydrofluoric acid, which is generally used in the form of 0.001-2 N, 
preferably 0.05-0.5 N, hydrofluoric acid, for example by refluxing for 
from 0.5 to 5, preferably from 1 to 3, hours. After the zeolite material 
has been isolated, for example by filtering it off and washing it 
thoroughly, it is advantageously dried at from 100.degree. to 160.degree. 
C. and calcined at from 450.degree. to 600.degree. C. In another 
embodiment, the zeolite material, after it has been molded with a binder, 
can be treated at elevated temperatures, for example from 50.degree. to 
90.degree. C., preferably from 60.degree. to 80.degree. C., for from 0.5 
to 5 hours, with 12-20% strength by weight hydrochloric acid. The zeolite 
material is then generally washed thoroughly, dried at from 100.degree. to 
160.degree. C. and calcined at from 450.degree. to 600.degree. C. An HF 
treatment may furthermore be followed by treatment with HCL. 
In another procedure, zeolites can be modified by applying phosphorus 
compounds, such as trimethoxyphosphate, trimethoxyphosphine or primary, 
secondary or tertiary sodium phosphate. Treatment with primary sodium 
phosphate has proven particularly advantageous. In this procedure, the 
zeolite in the form of extrudates, pellets or fluidizable material is 
impregnated with aqueous NaH.sub.2 PO.sub.4 solution, dried at 110.degree. 
C. and calcined at 500.degree. C. 
Other heterogeneous catalysts for the novel process are phosphates, in 
particular aluminum phosphates, silicon aluminum phosphates, silicon iron 
aluminum phosphate, cerium phosphate, zirconium phosphates, boron 
phosphate, iron phosphate or mixtures of these. 
In particular, aluminum phosphates synthesized under hydrothermal 
conditions are used as aluminum phosphate catalysts for the novel process. 
The aluminum phosphates prepared under hydrothermal conditions are, for 
example, APO-5, APO-9, APO11, APO-12, APO-14, APO-21, APO-25, APO-31 and 
APO-33. Syntheses of these compounds are described in European Pat. No. 
132,708 and U.S. Pat. Nos. 4,310,440 and 4,473,663. 
For example, AlPO-.sub.4.sup.-5 (APO-5) is synthesized by a method in which 
orthophosphoric acid is homogeneously mixed with pseudoboehmite (CATA 
SB.RTM.) in water, tetrapropyl ammonium hydroxide is added to this 
mixture, and the reaction is then carried out at about 150.degree. C. for 
from 20 to 60 hours under autogenous pressure in an autoclave. The 
AlPO.sub.4 filtered off is dried at from 100.degree. to 160.degree. C. and 
calcined at from 450.degree. to 550.degree. C. 
AlPO.sub.4.sup.-9 (APO-9) is likewise synthesized from orthophosporic acid 
and pseudoboehmite, but in aqueous DABCO solution 
(1,4-diazabicyclo[2.2.2]octane) at about 200.degree. C. under autogenous 
pressure in the course of from 200 to 400 hours. 
AlPO.sub.4.sup.-21 (APO-21) is synthesized from orthophosphoric acid and 
pseudoboehmite in aqueous pyrrolidone solution at from 150.degree. to 
200.degree. C. under autogenous pressure in the course of from 50 to 200 
hours. 
The silicon aluminum phosphates used for the novel process are, for 
example, SAPO-5, SAPO-11, SAPO-31 and SAPO-34. The synthesis of this 
compound is described in for example, European Patent 103,117 and U.S. 
Patent 4,440,871. SAPOs are prepared by crystallization from an aqueous 
mixture at from 100 to 250.degree. C. and under autogeneous pressure in 
the course of from 2 hours to 2 weeks, the reaction mixture of a silicon 
component, an aluminum component and a phosphorus component being reacted 
in aqueous solutions containing organic amines. 
For example, SAPO-5 is obtained by mixing SiO.sub.2, suspended in aqueous 
tetrapropylammonium hydroxide solution, with an aqueous suspension of 
pseudoboehmite and orthophosphoric acid, and then carrying out the 
reaction at from 150.degree. to 200.degree. C. in the course of from 20 to 
200 hours under autogenous pressure in a stirred autoclave. The powder 
which has been filtered off is dried at from 110.degree. to 160.degree. C. 
and calcined at from 450.degree. to 550.degree. C. 
Precipitated aluminum phosphates may also be employed as phosphate 
catalysts in the process. For example, an aluminum phosphate of this type 
is prepared by dissolving 92 g of diammonium hydrogen phosphate in 700 ml 
of water. 260 g of Al(NO.sub.3).sub.3. H.sub.2 O in 700 ml of water are 
added dropwise to this solution in the course of 2 hours. During this 
procedure, the pH is kept at 8 by the simultaneous addition of 25% 
strength NH.sub.3 solution. The resulting precipitate is stirred for a 
further 12 hours and then filtered off under suction, washed thoroughly 
and then dried at 60.degree. C. for 16 hours. 
Boron phosphates for the novel process can be prepared, for example, by 
mixing and kneading concentrated boric acid and phosphoric acid and by 
subsequent drying and Falcination in an inert gas, air or steam atmosphere 
at from 250.degree. to 650.degree. C., preferably from 300.degree. to 
500.degree. C. 
Modifying components as described above in the case of the zeolites can be 
applied to these phosphates by impregnation (immersion or spraying on) or, 
in some cases, by ion exchange. Modification with acids can also be 
carried out, as in the case of the zeolite catalysts. 
The catalysts described here can be used alternatively in the form of 2-4 
mm extrudates, tablets of 3-5 mm diameter or chips having particle sizes 
of from 0.1 to 0.5 mm or as a fluidizable catalyst. 
The novel reaction is preferably carried out in the gas phase or in the 
supercritical range from 100.degree. to 500.degree. C., in particular from 
200.degree. to 400.degree. C., using a WHSV of from 0.1 to 20 h.sup.-1, 
preferably from 0.5 to 5 h.sup.-1 (g of starting material per g of 
catalyst per hour). The molar ratio of unsaturated organic compound to 
PH-containing phosphorus compound is from 6:1 to 1:20, preferably from 3:1 
to 1:5. The reaction can be carried out in a fixed bed or fluidized bed. 
It is also possible to carry out the reaction in the liquid phase 
(suspension, trickle-bed or liquid-phase procedure) at from -20.degree. to 
200.degree. C. 
The process is carried out under atmospheric pressure or under 
superatmospheric pressures of from 0.5 to 500 bar, depending on the 
volatility of the starting compound, and is preferably effected 
continuously, although a batchwise procedure is also possible. 
Sparingly volatile or solid starting materials are used in dissolved form, 
for example in solution in tetrahydrofuran, toluene or petroleum ether. In 
general, the starting material may be diluted with solvents of this type 
or with inert gases, such as N.sub.2, Ar or steam. 
After the reaction, the resulting products are isolated by a conventional 
method, for example by distillation from the reaction mixture; unconverted 
starting materials may be recycled to the reaction. 
It is particularly advantageous to analyze the gaseous reaction mixture 
immediately and then to separate it into the individual components. A 
separation of this type can be carried out, for example, in a 
fractionating column.

The Examples which follow illustrate the invention. 
EXAMPLES 1-20 
The reaction is carried out under isothermal conditions in a metal 
autoclave or in glass ampoules. The reaction products are separated by a 
conventional method, for example in an apparatus under greatly reduced 
pressure, and are characterized by IR, NMR and MS spectroscopy. 
Quantitative determination of the reaction products and of the starting 
materials is carried out by gas chromatography or by weighing. In the 
experiments below, the batches were chosen so that the glass ampoule 
contained 75 millimoles of the starting mixture. This gave a reaction 
pressure of 8 bar at 100.degree. C. and 190 bar at 200.degree. C. 
The catalysts used for the novel process are: 
Catalyst A 
The borosilicate zeolite of the pentasil type is prepared in a hydrothermal 
synthesis from 640 g of finely divided SiO.sub.2, 122 g of H.sub.3 
BO.sub.3 and 8,000 g of an aqueous 1,6-hexanediamine solution (weight 
ratio 50:50) at 170.degree. C. under autogenous pressure in a stirred 
autoclave. The crystalline reaction product is filtered off, washed 
thoroughly, dried at 100.degree. C. for 24 hours and then calcined at 
500.degree. C. for 24 hours. This borosilicate zeolite is composed of 
94.2% by weight of SiO.sub.2 and 2.3% by weight of B.sub.2 O.sub.3. 
This material is molded with a molding assistant to give 2 mm extrudates, 
which are dried at 110.degree. C. for 16 hours and calcined at 500.degree. 
C. for 24 hours. 
Catalyst B 
An aluminosilicate zeolite of the pentasil type is prepared under 
hydrothermal conditions, under autogenous pressure and at 150.degree. C., 
from 65 g of finely divided SiO.sub.2 and 20.3 g of Al.sub.2 
(SO.sub.4).sub.3. 18 H.sub.2 O in 1 kg of an aqueous 1,6-hexanediamine 
solution (weight ratio 50:50) in a stirred autoclave. The crystalline 
reaction product is filtered off, washed thoroughly, dried at 110.degree. 
C. for 24 hours and then calcined at 500.degree. C. for 24 hours. This 
aluminosilicate zeolite contains 91.6% by weight of SiO.sub.2 and 4.6% by 
weight of Al.sub.2 O.sub.3. The catalyst is molded with a molding 
assistant to give 2 mm extrudates, which are dried at 110.degree. C. for 
16 hours and calcined at 500.degree. C. for 24 hours. 
Catalyst C 
Catalyst C is obtained by impregnating the extrudates of catalyst A with an 
aqueous Cr(NO.sub.3).sub.3 solution and then drying the product at 
130.degree. C. for 2 hours and calcining it at 540.degree. C. for 2 hours. 
The Cr content is 1.9% by weight. 
Catalyst D 
The iron silicate zeolite of the pentasil type is synthesized under 
hydrothermal conditions, under autogeneous pressure and at 165.degree. C., 
from 273 g of waterglass, dissolved in 253 g of an aqueous 
1,6-hexanediamine solution (weight ratio 50 : 50), and 31 g of iron 
sulfate, dissolved in 21 g of 96% strength sulfuric acid and 425 g of 
water, in a stirred autoclave in the course of 4 days. The zeolite formed 
is filtered off, washed thoroughly, dried at 110.degree. C. for 24 hours 
and calcined at 500.degree. C. for 24 hours. An iron silicate zeolite 
having an SiO.sub.2 /Fe.sub.2 O.sub.3 ratio of 17.7 and a Na.sub.2 O 
content of 1.2% by weight is obtained. The catalyst is extruded with 
finely divided SiO.sub.2 in a weight ratio of 70:30 to give 2.5 mm 
extrudates, which are dried at 110.degree. C. for 16 hours and calcined at 
500 .degree. C. for 24 hours. These extrudates are subjected to ion 
exchange with a 20% by weight strength NH.sub.4 Cl solution at 80.degree. 
C. and then washed chloride-free, dried at 110.degree. C., and calcined at 
500.degree. C. for 5 hours. Ion exchange is continued until the Na content 
is 0.002% by weight. 
Catalyst E 
Catalyst E is prepared in the same manner as catalyst C, except that 
Cr(NO.sub.3).sub.3 is replaced with Ce(NO.sub.3).sub.3. The Ce content is 
1.7% by weight. 
Catalyst F 
Silicon aluminum phosphate-5 (SAPO-5) is prepared from a mixture of 200 g 
of 98% strength phosphoric acid, 136 g of boehmite, 60 g of silica sol 
(30% strength), 287 g of tripropylamine and 587 g of H.sub.2 O. This 
mixture is reacted at 15.degree. C. in the course of 168 hours under 
autogenous pressure. The crystalline product is filtered off, dried at 
120.degree. C. and calcined at 500.degree. C. SAPO-5 contains 49.8% by 
weight of P.sub.2 O.sub.5, 33.0% by weight of Al.sub.2 O.sub.3 and 6.2% by 
weight of SiO.sub.2. SAPO-5 is molded with an extrusion assistant to give 
3 mm extrudates, which are dried at 120.degree. C. and calcined at 
500.degree. C. 
Catalyst G 
Commercial zirconium phosphate, Zr.sub.3 (PO.sub.4).sub.4, molded in pure 
form. 
Catalyst H 
BPO.sub.4 is prepared by combining 49 g of H.sub.3 BO.sub.4 with 117 g of 
H.sub.3 PO.sub.4 (75% strength) in a kneader, evaporating off excess water 
and molding the reaction product to give 3 mm extrudates. These extrudates 
are dried at 100.degree. C. and calcined at 350.degree. C. Catalyst H 
contains 8.77% by weight of B and 28.3% by weight of P. 
The experimental results obtained with these catalysts and the experimental 
conditions are summarized in Table 1. 
TABLE 1 
__________________________________________________________________________ 
Molar ratio 
Temperature Conversion 
Selectivity 
Example 
Catalyst 
Educt I 
Educt II I/II [.degree.C.] 
Product [%] [%] 
__________________________________________________________________________ 
1 A PH.sub.3 
##STR2## 2:1 200 
##STR3## 62 85 
2 A " " " 100 " 42 98 
3 C " " " 200 " 70 90 
4 B " " " 100 " 15 95 
5 D " " " 100 " 32 83 
6 A H.sub.3 CPH.sub.2 
" " 100 
##STR4## 41 92 
7 B " " " 100 " 39 91 
8 E " " " 100 " 21 70 
9 C " " 1:3 100 " 20 89 
10 C PH.sub.3 
##STR5## 1:1 200 
##STR6## 16 84 
11 C H.sub.3 CPH.sub.2 
" 1:4 200 
##STR7## 18 85 
12 C PH.sub.3 
C.sub.2 H.sub.4 
1:1 200 C.sub.2 H.sub.5 PH.sub.2 
7 80 
13 C PH.sub.3 
##STR8## 2:1 100 
##STR9## 10 85 
14 C " 
##STR10## 
2:1 100 
##STR11## 12 81 
15 C " 
##STR12## 
2:1 100 
##STR13## 19 79 
16 C " 
##STR14## 
2:1 100 
##STR15## 20 75 
17 F " 
##STR16## 
2:1 100 
##STR17## 15 87 
18 G " " 2:1 100 " 18 78 
19 H " " 2:1 100 " 25 82 
20 H CH.sub.3 PH.sub.2 
" 2:1 100 
##STR18## 7 71 
__________________________________________________________________________ 
.sup.(1) Including all isomers