Note: Descriptions are shown in the official language in which they were submitted.
~7Z57~
The present invention relates to a new process for
the preparation of phosphoric acid ester-halides and to new
phosphoric acid ester-halides obtainable with the aid of this
process.
It is known to prepare phosphoric acid ester-chlor-
ides by selective reaction of phosphoryl chloride with alcohols
(compare Houben-Weyl XII/2J page 212 (1964)). The disadvan-
tage of this process is that only a limited number of alcohols,
especially primary alcohols, can be used as the starting
material. Thus, the preparation of substituted compounds is
correspondingly restricted and in certain cases, for example
. for phosphoric acid alkyl ester-halides halogenated in the 1-
position in the alkyl radical, can be achieved in a controlled
manner at best via a multi-stage reaction sequence.
. A new process for the preparation of phosphoric
acid ester-halides has now been found which is characterised
in that a phosphoric acid ester of the general formula I
:~ o R'
-'. "/
X - P (I)
- R
. in which the radical R represents an alkoxy radical with 1 -
. 20 8 carbon atoms, which is optionally substituted by halogen,
`. and R' represents a Cl-C8 alkoxy radical which is optionally
substituted by halogen, or represents chlorine, bromine,
fluorine or a Cl-C6 alkyl or phenyl radical, which is option-
ally substituted by halogen, cmd X represents fluorine, chlorine
or bromine, is reacted simultaneously with a halogenating
agent and an
,' -.
_ z _
~'
'
.
~07Z~7~
olefine of the general ~ormula II
R2 ~ ~R4 (II)
", C = C
R
in which the radicals
R2 and R4 are identical or different and represent
hydrogen, halogen or a straight-chain or branched,
optionally substituted C1-C18 alkane, Cl-C6 acyloxy
or C2-C12 alkenyl radical, substituents which may be
mentioned being halogen, acyloxy or alkoxy groups with
1 - 18 carbon atoms, the isocyanate group, the isocya-
nide-dichloride group, the chlorocarbonyl group, the
ni-trile group or -the chlorosulphone group, a carb-
alkoxy group with 1-8 carbon atoms in the alcohol
radical or an optionally substituted carbamino group
with up to 12 carbon atoms in -the molecule, and also
represent a phenyl radical which is optionally sub-
stituted by halogen and/or by Cl-C4 alkyl groups and
the radical R4 also represents, in addition to the
. abovement~oned groups, the chlorocarbonyl or nitrile
group or a carbalkoxy radical or a carbamino radical,
which is optionally substituted on the nitrogen atom,
with9 in each case9 up to 9 carbon atoms in the mole-
cule, or represents an alkylcarbonyl, an alkylsulphonyl,
. an arylcarbonyl or an arylsulphonyl group with, in
each case, up to 7 carbon a-toms in the molecule or
~: 25 represents the aldehyde group and optionally the
radicals R2 and R4 conJointly are, as ~ result of an
additional bond between the radicals R2 and R4, a
: constituent o~ a 4-membered to 12-membered, pre~erably
Le A 16 296 - 3 -
. . .
; ..
.,, , , ! . , . , . . ~ .
~', . ~ '
1C~7;~57~
5 membered or 6-membered, carbocyclic or heterocyclic
ring, oxygen, sulphur or ni-trogen preferably occurring
as hetero-atoms, and
R3 and R5 are identical or different and represent
; 5 hydrogen, halogen or a Cl-C4 alkyl radical.
Preferred phosphoric acid esters, according to the
general formula I, which may be mentioned are those in which
R represents a Cl C6 alkoxy radical 9 preferentially
i; the methoxy and the ethoxy radical, and
R' represents a Cl-C4 alkoxy radical or represents a
Cl-C3 alkyl radical, chlorine, bromine, fluorine or
the phenyl radical and preferentially represents the
. methoxy, ethoxy, propoxy, isopropoxy, methyl or ethyl
radical and
X represents chlorine~
. Examples which may be mentioned are: phosphoric acid
dimethyl ester-monochloride, phosphoric acid diethyl ester-
: monochloride, phosphoric acid diethyl es-ter-monobromide,
- phosphoric acid dimethyl ester-monofluoride, phosphoric acid
dibutyl ester-monochloride, phosphoric acid monomethyl ester-
dichloride9 phosphoric acid monoethyl ester-dichloride,
phosphoric acid monoethyl ester-difluoride, phosphoric acid
mono-(2-chloroethyl) ester-dichloride, phosphoric acid monoiso-
.
propyl ester-dichloride, phosphoric acid monopropyl ester
dichloride, methanephosphonic acid monomethyl ester-chloride,
~ ethanephosphonic acid monoethyl ester-chloride and phenyl-
phosphonic acid monomethyl ester-chloride.
The phosphoric acid es-ters which are used for -the
. process according to the invention are known and can be
: 30 prepared by reacting the corresponding phosphoric acid chlo-
rides such as, for example, phosphoryl chloridel with the
. Le A 16 296 - 4 -
. ~
';~
'''
~L~7~574
apFropriate alcohols (compare ~ouben-Weyl, Methoden der
Organischen Chemie ~Methods of Organic Chemistry) Volume XII 9
: 2, page 211 (Stuttgar-t 1964)).
Preferred olefines, according to the general formula
II, which may be mentioned are those in which
R2 and R4 are identical or different and represent
hydrogen, fluorineJ chlorine, bromine or an optionally
substituted Cl-C5 acyloxy radical, a Cl-C6 alkane
radical or a C2-~6 alkenyl radical, substituents of
these radicals which may be mentioned being chlorine,
bromine, the isocyanate group, the isocyanide-dichlo-
ride group, the chlorocarbonyl group, the nitrile
group or the chlorosulphonyl group, a carbalkoxy
group, an acyloxy group or an alkoxy group with, in
each case, 1-5, and preferentially 1-3, carbon atoms
; in the molecule, as well as a carbamino group which is
; preferably substituted on the nitrogen atom by methyl
or ethyli and R2 preferentially represents fluorine,
chlorine or bromine and R4 has the abovementioned
scope of meanings but does not represen-t fluorine,
chlorine or bromine simultaneously wi-th R2.
Further preferred olefines which may be men-tioned are
those in which
.: 4
R represents the chlorocarbonyl group~ the nitrile
group~ a carbalkoxy group or a mono-alkylated or di-
alkylated carbamino group, with 1 to 5 carbon
atoms in the molecule, an alkylcarbonyl or alkyl-
sulphonyl group with 1 to 4 carbon atoms in the mole-
. cule and also an arylcarbonyl or arylsulphonyl group,
:~ 30 which preferably contains the phenyl radical as the
aryl radical, and
.: . Le A 16 296 - 5 -
'', ' '
. . .
~CJ7ZS'7~
preferentially the radicals R2, R3 and R5 are
identical or different and represent hydrogen,
chlorine, bromine or a Cl-C6 alkane radical and at
least one of the radicals R29 R3 and R5 represents
hydrogen.
Examples which may be mentioned of olefines which are
used for the process according to the invention are: branched
and unbranched alkenes, especially ethylene, propylene, but-l-
. ene and but-2-ene, isobutene, hex-l-ene 9 dodec-l-ene9 tri- and
tetra-propylene, tetraisobutene, oct-l-ene, octadec-l-ene,
l-phenyl-3,3,4,4-tetrafluoro~cyclo-butene, cyclopentene, cyclo-
hexene, cyclooctene, cyclododecene, styrene, ~-methylstyrene,
~- and ~-pinene and camphene; diolefines, especially buta-
193-diene, isoprene, 293-di.methyl-buta-1,3-diene, vinylcyclo-
hexene and cycloocta-1,4-diene; halogenated olefines, such as
allyl chloride, methallyl chloride and vinyl chloride9 1- and
2-chloropropene9 1,4- and 3,4 dichloro-but-2-ene, vinyl bro-
mide and allyl bromide, vinyl fluoride, 191-dichloroethylene9
l,l-difluoroethylene and tr:Lfluoromonochloroethylene, l-chloro-
cyclohexene and 3-chloro-cyclohexene; esters, mono- and di-
alkylamides, chloridesand nitriles of unsaturated carboxylic
acids, especially of acrylic acid, methacrylic acid, crotonic
acid, ~,~-dimethyl-acrylic acid, ~-chloroacrylic acid, ~
dichloroacrylic acid, vinylace-tic acid, undecenecarboxylic
acid, oleic acid, linoleic acid, cyclohexene-l-carboxylic
.~ acid and cyclohexene-3-carboxylic acid, maleic acid, itaconic
acid and fumaric acid; esters and ethers of unsa-turated
alcohols, especially of allyl alcohol, butene-1,4-diol and
methylene-propane-1,3-diol, for example ethyl vinyl ether,
butyl vinyl ether, vinyl acetate and isopropenyl acetate and
1,3-dioxolen-2-one; isocyanates and isocyanide-dichlorideswi-th
Le A 16 296 - 6 -
.,
.: .
~72~
olefinic groupings, especially allyl isocyanate and allyl
isocyanide-dichloride, 4-chloro-butenyl isocyanate and 4-
chlorobutenyl isocyanide-dichloride and isopropenyl iso-
cyanate; ketones and sulphones with olefinic groupings,
specially methyl vinyl ketone, mesityl oxide, phenylvinyl-
sulphone, sulpholene and 3-methylsulpholene; and olefinic
sulphonic acid derivatives, especially ~-chloro-vinyl-, allyl-
and methylallyl-, vinyl- and ~ -dimethylvinyl-sulphonyl
chloride.
Very particularly preferred olefines are those
according to the general formula II, in which R2 and/or R3
represent fluorine, chlorine or bromine, especially fluorine
or chlorine, and R also can represent hydrogen and the
radicals R4 and R5 in each case represent hydrogen, a Cl-C6
alkane radical or the phenyl radical. Examples which may be
mentioned are: monofluoroethylene, monochloroethylene, mono-
bromoethylene, l,l-difluoroethylene, l,l-dichloroethylene, 1-
fluoro-2-methylethylene, 1-fluoro-2-ethylethylene, l-fluoro-
2-phenyle~hyleneJ l-chloro-prop-l-ene and 2-chloro-prop-1-
ene.
The vinyl fluorides and vinylidene fluorides
: which are employed for the process according to the invention
are known or can be prepared according to known processes, for
example by an addition reaction of one molecule of HF with
.,,
appropriate acetylenes or, respectively, of two molecules of l-IF
with acetylenes, subsequent chlorination and dehydrochlori-
nation.
The phosphoric acid ester-halides obtainable by the
process according to the invention can be represented by the
.
~1~7Z57~
-~ general formula III
R~ R2 R4
O - C - C - Y (III)
R3 R5
in which the radicals
R', R2, R3, R4, R5 and X have the same meaning as ~or
the starting products of the general formula I or II
respectively and
Y represents chlorine or bromine, in accordance with
the halogenating agent used for the process according
to the invention.
Examples which may be mentioned o~ phosphoric acid
ester-halides, according to the general formula III, are:
Le A 16 296 - 8 _
.. .
~L~7Z57
~`
_. ...... _
_
. ~.
.. . _
C~ "
~ h r~
_ ~ p~ ~
.. ~ ~ V ~l U
O ~ O O O O V O ~ O
~ r~ ~I h r-l rl
V ~ V ~
~....................... . ~ - . I
., ~ ~ V~
~ .
~. .
.
Le A 16 296 - 9 -
:,
,: . .
~Ot7Z574
New compounds, which are obtainable with the aid of
the process according to the invention and which may be
mentioned are:
Compounds of the general formula III,
5 in which
X represents fluorine, chlorine or bromine,
Y represents chlorine or bromine,
R' represents a Cl-C8 alkyl radical or phenyl radical,
which are optionally substituted by halogen, and
R2 and R4 are identical or di~ferent and represent
hydrogen, halogen or a straight~chain or branched,
optionally substituted Cl-C18 alkane, Cl-C6 acyloxy
or C2~C12 alkenyl radical, substituents which may be
mentioned being halogen, acyloxy or alkoxy groups with
. 15 1 - 18 carbon atoms, the isocyanate group 9 the iso-
: cyanide-dichloride group, the chlorocarbonyl group, the
nitrile group or the chlorosulphone group, a carb-
. alkoxy group with 1-8 carbon atoms in the alcoholradical or an optionally substituted carbamino group
with up to 12 carbon atoms in the molecule, and also
represent a phenyl radical which is optionally sub-
; stituted by halogen and/or by Cl-C4 alk groups and
the radical R4 also represents, in addition to the
abovementioned groups, the chlorocarbonyl or nitrile
group or a carbalkoxy radical or a carbamino radical,
` which is optionally substituted on the nitrogen atom,
: with, in each case, up to 9 carbon atoms in the mole-
cule, or represents an alkylcarbonyl~ an alkyl
: sulphonyl, an arylcarbonyl or an arylsulphonyl group
with, in each case, up to 7 carbon atoms in the mole-
cule or represents the aldehyde group and ~pion~ly the
Le A 16 296 - 10 -
~7257~
radicals R2 and Rl conjointly are, as a result of an
additional bond between the radicals R2 and R4, a
constituent of a 4-membered to 12-membered, prefer-
ably 5~membered or 6-membered, carbocyclic or hetero-
cyclic ring, oxygen, sulphur or nitrogen preferably
occurring as hetero-atoms, and
R3 and R5 are identical or different and represent
hydrogen, halogen or a Cl-C4 alkyl radical,
and also compounds of the general formula III 9
in which
X represents fluorine, chlorine or bromine,
Y represents chlorine or bromine,
R' represents a Cl-C8 alkoxy radical, which is option-
ally substituted by halogen, or represents fluorine,
chlorine or bromine,
R2 represents fluorine,
R3 represents fluorine or hydrogen and
R and/or R5 represents hydrogen, Cl-C4 alkyl or
phenyl.
The compounds listed in Table 1 may be mentioned by
way of example:
Le A 16 296 - 11 -
:
~ ~ .
., .
~7Z~7~
_ _ _ _
U~ W ~ W ~ W
. _ . .
,' - - .
~ 1~ F~ W W 1~ W P~ W P t~l P:l ~
.~ .
c*l h 1~ h h ¢- h F~ h h F~1 h P~ q F~ F~ h
. ~; O O O O U~
W :C W Pq C~l r I ~1 ~1 ~ h W W c~ ~ ~D
.~ u v o v v c~ c~ o c~ ~ m o v v v o
"., ~. . ~
.- ~ ,I r l h r~ I h r~ h r~l r~ ~ h ~I r-1 ~1
.~. C~ C~ q V ~ v ~ v
. ~
0 r-l ~1 ~1 ~ ~1 ~1 ~-1 ~( h ~1 ~
E-l ~ v r~ ,
.
`'' .
' '
;:
Le A 16 296 - 12 _
~7Z5~4
Elementary halogen, especially chlorine or bromine,
can be used as the halogenating agent for the process
according to the invention. Of course, compounds which split
off chlorine or bromine under the reaction conditions, for
example sulphuryl chloride, can also be employed.
The reaction temperature for the reaction according to
the process of the invention is not in itself critical and
can vary within wide limits. In general, the reaction is
carried out at between -50 and + 120C, appropriately between
about -10 and +100C and preferably at -10 to +50C.
In general, the reaction is carried out under normal
pressure.
~; The process according to the invention is preferably
carried out in the presence of solvents or diluents. ~ol-
vents and diluents which can be used are organic solvents
which are inert towards the reactants, such as, for example,
aliphatic and aromatic chlorinated hydrocarbons, dichloro-
methane, chloroform7 chlorobenzene or dichlorobenzene but also
an excess of the particular phosphoric acid ester-halide, in
so far as this is liquid under the reaction conditions.
In some cases it has also proved advantageous to add
~-~ a small amount of Friedel-Crafts catalysts, especially7 for
example, iron-(III) chloride, zinc chloride or aluminium
chloride, to the reaction mixture.
In order to achieve good yields, the process according
to the invention is appropriately carried out using equiva-
lent amounts of halogena-ting agent and at least equivalent
amounts of the phosphoric acid ester-halide employed as the
' starting material, these amounts being based on -the olefine.
In general, particularly good results are obtained when the
phosphoric acid ester-halide employed is used in excess, for
Le A 16 296 - 13 -
.
.' '
~i~7Z57~
example in a molar ratio of 1 : 1 to 5 : 1, based on olefine
employed.
Using, as an example, the reaction of phosphoric
acid monomethyl ester-dichloride with vinyl chloride as the
olefine and chlorine as the halogenating agent, the process
according to the invention can be illustrated in more detail
by the equation which follows:
:` ~
/ Cl
Cl - P ~ CH2=CH-Cl ~ C12
O-CH3
, /.Cl
) Cl - P ~ CH3Cl
OCH-CH2-Cl
Cl
:
~hen the phosphoric acid ester used as the start-
ing material contains two alkoxy groups as the substituents R
and R', the reaction according to the process of the invention
can be continued stepwise, when an appropriate excess of ole-
fine and halogenating agents are present, by substitution
of both alkoxy groups to give two new phosphoric acid diestermono-
halides, as is illustrated in more detail by the equation
which follows, using, as an example, the reaction of phosphoric
acid dimethyl ester-monochloride with vinyl fluoride as the
olefine and chlorine as the halogenating agent:
. .
`~ zs~
Cl 11/C~3 C12 gC~2_C~TF~ Cl ll/ocrl3
OC~3 CH3Cl \ 0-CII~
~Ir~Cl
'' 7ll2 Cl
Cl Cl~ C}IF 11~ CIIF
~ll2¢
, . .
In this case the phosphoric acid ester-halide
obtainable as the product contains, in place of the radical
R', the radical R2R4 .
--O--C--C--Y
3 5
R R
In order to carry out the process according to the
invention in practice it is appropriate initially to intro-
duce the phosphoric acid ester-halide employed, if necessary
' in an inert solvent or diluent, and to add the halogenating
` 10 agent and the olefine simultaneously to this solution at the
indicated temperatures, the internal temperature of the mix-
ture being regulated by external cooling. After the reaction
has subsided, the batch is stirred for a further period whilst
warming (preferably at 40 to 100C) in order to carry the
` 15 reaction to completion. The reaction mix-ture is then cooled
to room temperature and worked up according to customary
methods, for example by ~ractlonal vacuum distillation.
The products obtainable according to the process of
; the invention are generally obtained in the form of colour-
less to pale yellow coloured oils, which are insoluble in
water and which generally can be distilled without decom-
position under reduced pressure and can be purified in this
Le A 16 296 - 15 -
",
';
,
.,
~(97Z57~
way. When mixtures of different isomers are obtained as the
product, these can be separated by fractional distillation.
An advantage of the process according to the inven-
tion is that the preparation of known phosphoric acid ester-
halides is considerably simplified and numerous new compounds
of this type, whlch cannot be prepared according to methods
known hitherto, are accessible.
A further advantage is that the process according
to the invention has universal applicability and can be car-
ried out industrially in a simple manner and that the requisite
starting materials are readily accessible. The high purity
and good yields of the products obtainable by the process accor-
ding to the invention is also advantageous.
The phosphoric acid ester-halides which can be
prepared according to the process of the invention serve as
intermediate products for the preparation of insecticides and
flameproofing agents ~compare United States Patent Specification
2,947,773/Table 1).
Example 1
55 g of vinyl fluoride and 70 g of chlorine are
simultaneously passed into 308 g of phosphonic acid dimethyl
ester-monochloride ~CH30)2POCl at -5C to 0C, whilst stirring
and cooling. After the reaction has taken place, the mix-
ture is first degassed in vacuo at room temperature and then
is subjected to fractional distillation. 143 g ~= 69% of
theory) of phosphoric acid 0-methyl-0-~2-chloro-1-fluoro-
ethyl) ester-monochloride of the formula
Cl-PO(OCH3) tOCHF-CH2Cl) which has a boiling range b.p. 0 3:
69 - 72C, and 11 g ~= 8% of theory) of phosphoric acid di-
(2-chloro-1-fluoroethyl) ester-monochloride of the formula
Cl-PO(OCHF-CII2Cl)2 which has a boiling range b.p. 0 2:
- 16 -
':
;
~0~;~57~
85 - 90C, are obtained.
The reaction is carried out analogously to Example 1,
using 600 g of (CH30)2P0cl~ 195 g of C12 and 140 g of vinyl
fluoride, instead of the amounts indicated in Example 1.
In this case 307 g (52% of theory) of the compound
Cl-PO(OCH3)(0CHF-CH2-Cl) and 72 g (= 21.5%) of the compound
Cl-PO(OCHF-CH2Cl)2 are obtained.
Example 3
71 g of chlorine and 90 g of vinyl chloride are
passed into 172 g of phosphoric acid diethyl ester-mono-
chloride Cl-PO(OC2H5)2. The temperature is kep-t at about
0C by cooling. The reaction mix-ture is warmed to 50C in
, order to remove ethyl chloride and is then subjected -to
fractional distillation in vacuo. 105 g (= 43.5% of theory)
of phosphoric acid 0-ethyl-0-(1,2-dichloroethyl) ester-mono-
chloride of the formula Cl-PO(OC2H5)(0CHCl-CH2Cl), which has
a boiling point b.p.o 1 : 72C, and 52 g (= 33.4% of theory)
of phosphoric acid di-(1,2 dichloroethyl) ester-monochloride
Cl-PO(OCHCl-CH2C1)2, which has a boiling point b.p.o 1 :
110C, are obtained.
E~ple 4
70 g of vinyl fluoride are passed into 212 g of
Cl_PO(OCH3)2 a-t about 0C, whilst stirring and cooling, 117 g
of bromine ~eing added dropwise at the same time. The mix-
ture is then degassed under a waterpump vacuum and subjected
: to fractional distillation. 120 g (- 65% of theory) of
phosphoric acid 0-methyl-0-(2-bromo-1-fluoroethyl) ester-
monochloride of the formula Cl-PO(OCH3)(0CHF_CH2Br), which
has a boiling range b.p.o 2 : 80 - 83C, and 14 g of the
compound Cl-PO(OC`HF-CH2Br)2, which has a boiling range of
` Le A 16 296 - 17 -
. .
' .
. , .
. .
'.'
; .
~C17Z574
100 - 105 / 0.15 mm Hg, are obtained.
20 g of chlorine and 20 g of vinyl fluoride are
passed into 20 g of phosphoric acid monopropyl ester-di~
chloride C12P0-0-nC3H7 at -10C to 0C. 20-2 g (= 85% of
; theory, based on phosphoric acid propyl ester-dichlorideemployed) of phosphoric acid (2-chloro-1-fluoroethyl) es-ter-
dichloride of the formula C12P0-OCHF-CH2Cl, which has a
bolling range of 46 - 48C/0.2 mm Hg 9 are obtained by
fractional distillation.
_6
30 g of vinyl fluoride and 40 g of chlorine are
passed into 80 g of phosphoric acid monoethyl ester-dichloride
at about 0C. After working up by fractional distillation,
75 g (= 77.5% of theory, based on phosphoric acid ethyl ester-
chloride employed) of the compound C12P0-0-CHF CH2Cl, which
has a boiling range of 43 - 46C/0.1 mm Hg, are obtained.
Example 7
20 g of vinyl chloride and 20 g of chlorine are
passed into 20 g of phosphoric acid monopropyl ester-dichloride,
the reaction temperature being kept between 0C and +10C by
cooling. Working up by distillation gives 16 g (= 62.5% of
theory) of phosphonic acid (1,2-dichloroethyl) ester-
dichloride, which has a boiling range of 56 - 60C/0.1 mm Hg.
Example 8
80 g of vinyl bromide are added dropwise to 80 g of
phosphoric acid monoethyl ester-dichloride at -5C to 0C,
45 g of chlorine being passed in simultaneously and the heat
of reaction being compensated by a cooling ba-th. 52 g (= 40%
of theory) of the compound CH2Cl-CH~r-0-POC12, which has a
boiling range of 66 68C/0.1 mm Hg, are obtained by frac-
Le A 16 296 - 18 -
:'.
~ILC)7ZS~
tional distillation of the resulting product mixture.
E~ample 9
100 g of chlorine and 65 g of vinyl fluoride are
simultaneously introduced into 135 g of ethane phosphonic
acid ethyl ester chloride. The temperature is kept at bet-
ween -10C and 0C by means of cooling. After working up by
frac-tional distillation, 120 g (= 67 % of the theory) of
ethane phosphonic acid (2-chloro-1-fluoroethyl ester)
chloride, which has a boiling range of 65 - 67 C / 0.2 mm Hg,
are obtained.
Example 10
60 g of chlorine, 39 g of vinylidene fluoride and
in addition 0.5 g of FeC13 are introduced into 67 g of
phosphoric acid methyl ester dichloride. The temperature
is kept at 10 to 20C by means of cooling. After working
up by fractional distillation in vacuo, 75 g (75 % of the
theory) of phosphoric acid (2-chloro-191-difluoro-ethyl
ester)-dichloride, which has a boiling range of 45 - 50c/
4 mm Hg, are obtained.
Le A 16 296 - 19 -
'
