USOO566335 8A
United States Patent [19]
[11]
[45]
Cohen et al.
[54] PROCESS FOR ‘THE PREPARATION OF
ORGANOSILICON DISULFIDE
COMPOUNDS
Patent Number:
Date of Patent:
5,663,358
Sep. 2, 1997
4,820,751
4/1989 Takeshita et al. .................... .. 523/215
5,440,064
8/1995 Agostini et a1. ...................... .. 556/427
FOREIGN PATENT DOCUMENTS
[75] Inventors: Martin Paul Cohen, Fair1awn; Lawson
Gibson Wideman, Tallmadge, both of
Ohio
0676443
124400
3/1995
6/1984
European Pat. Off. ........ .. C08K 3/36
Japan ............................ .. C08L 21/00
OTHER PUBLICATIONS
[73] Assignee: ‘The Goodyear Tire & Rubber
Company, Akron, Ohio
Brzezinska, E, and Ternay, Andrew L, J. Org. Chem. 1994,
59. 8239-8244, “Disul?des. 1. Synthesis Using 2,2',—Dithio
[21] Appl. No.: 589,283
The Abstract for JP 7228588-A relates to sulfur-containing
bis(benzothiazo1e):”.
[22] Filed:
organosilicon compounds which are prepared by reacting
Jan. 22, 1996
[51]
Int. Cl.6 ......................... .. C07D 277/80; C07F 5/02;
[52]
US. Cl. ........................ .. 548/166; 556/469; 556/478;
[58]
Field of Search ........................... .. 548/166; 556/469,
C07F 7/08
556/482; 556/487; 556/489
556/478, 482, 487, 489
[56]
U.S. PATENT DOCUMENTS
4,390,648
6/1983 Stacy .................... ..
[57]
-
ABSTRACT
reacting a mercaptoalkoxysilane with a sulfenamide com
10/1973 Hess et al. ............................ .. 152/330
3,842,111 10/1974 Meyer-Simon
Primary Examiner—]ohann Richter
Assistant Examiner-Jane C. Oswecki
Attorney, Agent, or Firm-Bruce J. Hendricks
The present invention relates to a process for the preparation
of organo silicon disul?de compounds. The process involves
References Cited
3,768,537
sodium sul?te with sulfur to give sodium polysul?de fol
lowed by an in situ reaction with a haloalkoxysilane.
pound.
.. 260/4482
523/216
14 Claims, No Drawings
5,663,358
1
2
(a) a sulfenamide compound of the formula
PROCESS FOR THE PREPARATION OF
ORGANOSILICON DISULFIDE
COMPOUNDS
N
BACKGROUND OF THE INVENTION
/
S
The present invention relates to a process for the prepa
, ration of organosilicon disul?de compounds. Organosilicon
disul?des are known adhesion promoters in sulfur
vulcanizable rubber mixtures reinforced with inorganic
materials such as glass SiOZ, aluminosilicates and carbon
10
R5
hydrogen, acyclic aliphatic groups having from 1 to 10
carbon atoms and cyclic aliphatic groups having from
5 to 10 carbon atoms; and R5 is selected from the group
consisting of acyclic aliphatic groups having 1 to 10
carbon atoms and cyclic aliphatic groups having from
5 to 10 carbon atoms; with
mercaptopropyl trimethoxy silane or mercaptopropyl tri
theoretical.
C-S-N
where R4 is selected from the group consisting of
black For example, in GB 1,484,909, there is disclosed a
process for the preparation of organo trialkoxysilane disul
?des. In accordance with the teachings of this reference,
ethoxy silane is reacted with sulfuryl chloride in an inert
solvent at temperatures of from 0° to 100°. The disul?de is
then obtained by fractional distillation. The yields of desired
product range in the neighborhood of 63 to 65 percent of
R4
15
(b) a mercaptosilane compound of the formula
wherein Z is selected from the group consisting of
'
US. Pat. No. 3.842.111 discloses a method for the prepa
20
R3
ration of organosilicon disul?de- compounds by oxidizing
mercaptoalkoxysilanes. Representative oxidizing agents
include oxygen, chlorine, halogens of atomic weight 35 to
.127, nitric oxide, sulfuryl chloride and sulfoxides.
Generally speaking, organosilicon disul?de compounds
25
wherein R2 may be the same of di?erent and is inde
pendently selected from the group consisting of an
are very expensive and, with the increasing interest in
silica-reinforced vulcanizable rubber. more cost-ef?cient
alkyl group having 1 to 4 carbon and phenyl; R3 may
methods of preparing these compounds are needed.
SUMMARY OF THE INVENTION
be the same of different and is independently selected
30
The present invention relates to a process for the prepa
ration of a organosilicon disul?de compounds. The present
invention may be used to prepare symmetrical organosilicon
disul?de compounds of the formula
35
ration of organosilicon disul?de compounds. Representative
organosilicon disul?de compounds of formula I which may
be prepared in accordance with the present invention include
2 ,2'-bis(trimethoxysilylethyl) disul?de; 3 ,3 '-bis
formula
(trimethoxy silylpropyl) disul?de; 3 ,3'-bis
(triethoxysilylpropyl) disul?de; 2,2'-bis(triethoxysilypropyl)
disul?de; 2,2'-bis(tripropoxysilylethyl) disul?de; 2,2'-bis
(tri-sec-butoxysilylethyl) disul?de; 2,2'-bis(tri-t
butoxysilylethyl)
disul?de;
3,3'-bis
(triisopropoxysilylpropyl) disul?de; 3 ,3'-bis
(trioctoxysilylpropyl) di sul?de; 2 ,2'-bis(2'
and mixtures thereof, wherein Z is selected from the group
consisting of
50
wherein R2 may be the same or di?cerent and is indepen
dently selected from the group consisting of analkyl group
55
atoms and a substituted or unsubstituted arylene group
having a total of 6 to 12 carbon atoms.
DETAILED DESCRIPTION OF THE
INVENTION
There is disclosed a process for the preparation of orga
nosilicon disulfide compounds comprising reacting
8 carbon atoms and cycloalkoxy groups with 5 to 8
carbon atoms; and R1 is selected from the group
consisting of a substituted or unsubstituted alkylene
group having a total of 1 to 18 carbon atoms and a
substituted or unsubstituted arylene group having a
total of 6 to 12 carbon atoms.
The present invention relates to a process for the prepa
unsymmetrical organosilicon disul?de compounds of the
having 1 to 4 carbons and phenyl; R3 may be the same or
different and is independently selected from the group
consisting of alkoxy groups having 1 to 8 carbon atoms and
cycloalkoxy groups with 5 to 8 carbon atoms; and R1 is
selected from the group consisting of a substituted or
unsubstituted alkylene group having a total of 1 to 18 carbon
from the group consisting of alkoxy groups having 1 to
65
ethylhexoxysilylethyl) disul?de; 2,2'-bis(dimethoxy
ethoxysilylethyl)
disul?de;
3,3'-bis
(methoxyethoxypropoxysilylpropyl) disul?de; 3,3'-bis
(dimethoxymethylsilylpropyl) disul?de; 3,3'-bis(methoxy
dimethylsilylpropyl) disul?de; 3,3'-bis
(diethoxymethylsilylpropyl) disul?de; 3 ,3'-bis
(ethoxydimethylsilylpropyl) disul?de; 3,3'-bis(cyclohexoxy
dimethylsilylpropyl) disul?de; 4,4‘-bis
(trimethoxysilylbutyl) disul?de; 3,3'-bis(trirnethoxysilyl-3
methylpropyl) disul?de; 3 ,3'-bis(tripropoxysilyl-3
methylpropyl) disul?de; 3,3'-bis(dimethoxy methylsilyl-3
ethylpropyl) disul?de; 3 ,3 '-bis(trimethoxysilyl-2
methylpropyl) disul?de; 3,3'-bis(dimethoxyphenylsilyl-2
methylpropyl) disul?de; 3,3'-bis(trimethoxysilylcyclohexyl)
disul?de; 12,12'-bis(trimethoxysilyldodecyl) disul?de;
l2,l2'-bis(triethoxysilyldodecyl) disul?de; 18, 18'-bis
(trimethoxysilyloctadecyl) disul?de; 1 8 , 1 8’-bis
(methoxydimethylsilyloctadecyl) disul?de; 2.2'-bis
(trimethoxysily1-2-methylethyl) disul?de; 2,2'-bis
5,663,358
5
6
The molar ratio of the compound of formula 111 to the
compound of formula IV may range from 1:5 to 5:1.
Preferably, the molar ratio ranges from 1:3 to 3:1 with a
range of from 1:1 to 1:2 being particularly preferred As can
EXAMPLE 3
be appreciated by the teachings herein, by varying the molar
Preparation ofrBis(3-Triethoxysilyl)Propyl Disul?de
5
ratio of the compound of formula I[[ to the compound of
A l-quart (0.9461) glass reactor was charged with 400 ml
of mixed xylenes, 23.9 g (0.10 mole) of N-t-butyl-2
benzothiazolesulfenamide, 47.6 g (0.20 mole) of
formula IV, one produces varying weight percentage of the
symmetrical organosilicon disul?de of formula I and the
unsymmetrical organosilicon disul?de for formula II.
3-mercaptopropyltriethoxysilane and shaken for a few
minutes, wherein an exotherm to 33° C. was observed and
The reaction should be conducted in the absence of water
because the presence of a alkoxysilane moiety may be
a thick off-white-to-yellow-brown precipitate began to form.
The reaction was stirred for 4 hours, ?ltered and stripped
under 29 inches of Hg vacuum, to give 40.0 g of a liquid
hydrolysed by contact with water.
The reaction of the present invention may be conducted in
product containing 97 percent by weight of bis
the presence of an organic solvent. Suitable solvents which
may be used include chloroform, dichloromethane, carbon
(3-triethoxysilyl)propyl disul?de, as determined by GPC
and mass spectrometric analysis. The precipitate weighed
tetrachloride, hexane, heptane. cyclohexane, xylene,
benzene, dichloroethylene, trichloroethylene, dioxane,
30.6 g and was determined to be mercaptobenzothiazole.
What is claimed is:
diisopropyl ether, tetrahydrofuran and toluene. As indicated
1. A process for the preparation of organosilicon disul?de
compounds of the formula
above, care should be exercised to avoid the presence of
water during the reaction. Therefore, none of the above
solvent should contain any appreciable levels of water.
Preferably, the organic solvent is chloroform, heptane,
xylene, cyclohexane or toluene.
The reaction may be conducted over a variety of tem
peratures. Generally speaking, the reaction is conducted in a
temperature ranging from 20° C. to 140° C. Preferably, the
25
reaction is conducted at a temperature ranging from 50° C.
to 90° C.
The process of the present invention may be conducted at
a variety of pressures. Generally speaking, however, the
8
30
reaction is conducted at a pressure ranging from 0.96 to 4.83
(a) a sulfenamide compound of the formula
kglcmz.
N
EXAMPLE 1
Preparation of 2-Benzothiazyl-(3-Triethoxysilyl)
comprising reacting
\\c s N/
35
/
S
Propyl Disul?de and Bis (3-Triethoxysilyl)Propyl
Disul?de
R4
R5
where R4 is selected from the group consisting of
A l-quart (0.946 1) glass reactor was charged with 400 ml
of mixed xylenes, 25.1 g (0.10 mole) of N-cyclohexyl-2
benzothiazolesulfenamide, 23.8 g (0.10 mole) of
hydrogen, acyclic aliphatic groups having from 1 to 10
carbon atoms and cyclic aliphatic groups having from
3-mercaptopropylt?ethoxysilane and shaken for a few
minutes, wherein an exotherm to 32° C. was observed and
consisting of acyclic aliphatic groups having 1 to 10
carbon atoms and cyclic aliphatic groups having from
5 to 10 carbon atoms; and R5 is selected from the group
a thick oif-white-to-yellow precipitate began to form. The
5 to 10 carbon atoms; with
reaction was stirred for 4 hours, ?ltered and dried under 29 45
inches of Hg vacuum. to give 18 g of a liquid product
(b) a mercaptosilane compound of the formula
containing 27.2 percent by weight of 2-benzothiazyl-(3
tn'ethoxysilybpropyl disul?de and 42.7 percent by weight of
his (3-triethoxysi1yl)propyl disul?de, with 19 percent by
weight of starting material as determined by GPC and mass
50
wherein Z is selected from the group consisting of
spectrometric analysis.
' EXAMPLE 2
Preparation of Bis(3-Triethoxysilyl)Propyl Disul?de
55
A l-quart (0.9461) glass reactor was charged with 400 ml
of mixed xylenes, 25.1 g (0.10 mole) of N-cyclohexyl-2
benzothiazolesulfenamide, 47.6 g (0.20 mole) of
wherein R2 may be the same or diiferent and is inde
pendently selected from the group consisting of an
alkyl group having 1 to 4 carbon atoms and phenyl; R3
3-mercaptopropyltriethoxysilane and shaken for a few
minutes, wherein an exotherm to 33° C. was observed and
may be the same or diiferent and is independently
selected from the group consisting of alkoxy groups
having 1 to 8 carbon atoms and cycloalkoxy groups
with 5 to 8 carbon atoms; and R1 is selected from the
group consisting of a substituted or unsubstituted alky
a thick off-white-to-yellow-brown precipitate began to form.
The reaction was stirred for 4 hours, ?ltered and stripped
under29 inches of Hg vacuum, to give 44.5 g of a liquid
product containing 98 percent by weight of bis
3-triethoxysilyl)propyl disul?de, as determined by GPC and
mass spectrometric analysis. The precipitate weighed 38.4 g
and was determined to be mercaptobenzothiazole.
65
lene group having a total of 1 to 18 carbon atoms and
a substituted or unsubstituted arylene group having a
total of 6 to 12 carbon atoms.
5,663,358
10
9
rnethylpropyl-u-ipropoxysilane, 3-mercapto-3-ethylpropyl
9. The process of claim 1 wherein the reaction is con
ducted in absence of water and in the presence of an organic
dimethoxy methylsilane , 3 -mercapto-2-methylpropyl
trimethoxysilane. 3-rnercapto-2-methylpropyl dimethoxy
phenylsilane~ 3-rnercaptocyclohexyl-trimethoxysilane,
12-mercaptododecyl trirnethoxy silanev~
l2-mercaptododecy1 lriethoxy silane, 18-mercaptooctadecyl
trimethoxysilane,
l8-mercaptooctadecyl
methoxydirnethylsilane, 2-mercapto-2-methylethyl
solvent selected from the group consisting of chloroform,
dichloromethane, carbon tetrachloride, hexane, heptane,
cyclohexane, xylene, benzene, dichloroethylene,
trichloroethylene. dioxane, diisopropyl ether, tetrahydrofu
ran and toluene.
tripropoxysilane, 2-mercapto-2-methy1ethy1
trioctoxy silane, 2-mercaptophenyl trimeth oxysilane,
Z-mercaptophenyl triethoxysilane; 2-rnercaptotolyl tri
methoxy silane; 2-mercaptotolyl triethoxysilane;
2-mercaptomethylto1yl trimethoxysilane;
Z-mercaptomethyltolyl
triethoxysilane;
2-mercaptoethylphenyl trimethoxysilane;
2-mercaptoethylphenyl
triethoxysilane;
2-mercaptoethyltolyl
trimethoxysilane;
Z-mercaptoethyltolyl
triethoxysilane;
3-mercaptopropylphenyl trimethoxysilane;
3-mercaptopropylphenyl triethoxysilane;
S-mercaptopropyltolyl trimethoxysilane; and
3-mercaptopropyltolyl lriethoxysilane.
15
10. The process of claim 1 wherein the reaction is
conducted at a temperature ranging from 20° C. to 140° C.
11. The process of claim 10 wherein the reaction is
conducted at a temperature ranging from 50° C. to 90° C.
12. The process of claim 1 wherein the reaction is
conducted at a pressure ranging from 0.096 to 4.83 kglcmz.
13. The process of claim 5 wherein said organosilicon
disul?de of formula I is 3,3'-bis(triethoxysilylpropyl) disul
?de.
14. The process of claim 6 wherein said organosilicon
disul?de of formula II is 2-benzothiazyl-(3-triethoxysi1yl)
propyl disul?de.