close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3082277

код для вставки
March 19, 1963
E. A. HUNTER ETAL
3,082,267
INDANE SYNTHESIS
Filed March 1, 1960
I
LO
I
I0
o
I0
m
LU
~ 5
_|
>
:|:
)
o
LU
N
TEHCYO‘DURLMPNXIE—,
VS.
I.
z
MCPEISTOYHLNRETM
m
o
‘2
n:
w
n.
u:
/
9 6'
E
I,
/
l
/
LO
IO
N
0
N
‘2
0
Ln
Edward Allen Hunter
Clyde Lee Aldrldge
By
o
Inventors
#m a. WM
Patent Attorney
Unitedv States Patent 0 rice
1
3,082,267
Patented Mar. 19, 1963
2
(3)
3,082,267
INDANE SYNTHESIS
Edward Allen Hunter and Clyde Lee Aldridge, Baton
O-om'omom- ----> II- +
Rouge, La., assiguors to Esso Research and Engineering
Company, a corporation of Delaware
5
Filed Mar. 1, 1960, Ser. No. 12,049
H-reinitiates reaction
(4)
10 Claims. (Cl. 260-668)
The telomerization side reaction to ‘form alkyl 'benzenes
is well known. Chemically the structure of the alkylated
The present invention relates to an improved process
for the production of indanes. More particularly, this
benzene compound produced may be represented by the
invention relates to a process wherein an alkyl benzene 10 formula:
compound is reacted with ethylene in the presence of free
radicals under carefully chosen reaction conditions.
Thus, high yields of indanes are obtained along with
the production of alkyl benzene compounds having on
the average less than 7 carbon atoms in the
Most particularly, this invention relates to
alkyl aromatic with 2 to 20 mol percent
at temperatures of 200~350° C., pressures
alkyl group.
reacting an
of ethylene
of 400-800
p.s.i.g., in the presence of a reaction initiator.
This re
wherein R and R’ are hydrogen or an alkyl‘ group and
n is an integer which under the preferred conditions of
operation presently disclosed will be 1 to 3 for most of
the product.
It should be noted that both R and R’
in the above formula are present in the alkyl benzene
action‘initiator may be a compound which decomposes 20 starting material reacted with ethylene.
'
thermally to yield'free radicals, e.g. a peroxide or the
The conditions for carrying out the present invention
free radicals may be generated by such expedients as
are as follows: Temperatures of 200 to 350° F., pref
exposing the reaction mixture to ionizing radiation.
‘According to the present invention it has now been
discovered that extremely valuable indanes may be pro
duced from inexpensive alkyl benzene compounds (such
erably 250 to 300° F.; pressures of 400 to 800 p.s.i.g.,
preferably 500 to 700 p.s.i.g.; mol ratio of ethylene to
alkylated benzene in the range of 2 to 20 mol percent,
preferably 5 to 15 mol percent ethylene. Reaction times
may be from 0.25 to 10 hours, preferably 2 to 5 hours.
as toluene) and ethylene. The reaction of these com
' pounds to produce long chain alkyl benzene compounds
' Where the reaction‘ initiator is an unstable material quan
is known in the art. Surprisingly it has now been dis
titles of “catalyst” are suitably in the range between about
covered over said known reactions that by drastically 30 0.1% and about 5% by weight on the alkyl benzene
limiting the amount of ethylene supplied and by control
of the pressures and temperatures utilized it is possible to
obtain cyclization rather than a growth of thev alkyl
' chain.
Thus, s'electivities per pass to indane of about
' 20 to 30 wt. percent may be obtained, which, of course,
can be increased by recycling the alkyl benzene product
' also obtained in the process. It should be noted that the
- alkyl benzene side product contains on the average only
3 to 6 carbon atoms in the alkyl chain as compared to
the average of 7 to 20 carbon atoms in the alkyl chain
- obtained in the prior art processes.
'
According to the present invention the indanes or sub
stituted indanes may be‘p'repared by reacting ethylene
with alkyl benzene compounds having at least one alkyl
group containing not more than 10 carbon atoms, said
alkyl group having at least one hydrogen atom attached
to a saturated carbon atom alpha to the benzene ring.
reactant. Much of the catalytic effect is usually ob
tained by use of about 0.5 to 1% of catalyst by weight
on the alkyl benzene reactant, with relatively small in
35 crease in yield for larger amounts, and accordingly use
of 0.5 to 1 weight percent of catalyst is generally pre-'
ferred. Increasing amounts of catalyst tend generally to
decrease the amount of residue formed, i.e. high boiling
1 material.
The alkyl benzene may ‘also be advantageously diluted
with about 1 to 4 moles of an inert diluent, preferably
‘a hydrocarbon diluent (e.g. benzene) per mole of alkyl
benzene, in order to increase the ratio of indanes to alkyl
benzenes obtained in the products. Since these diluents
must be inert in the reaction carried out most materials
such as paraf?ns and cyclopara?’ins are unsuitable. There
fore, as mentioned above, preferably the diluent is ben
zene, which is inert in the reaction, cheap, and easily
~ The compound preferably has no additional substitutions,
separated from the products by distillation.
additional alkyl substituents being particularly undesirable 50 Systems which may be used to initiate the reaction,
because this multiplicity of reaction sites permits the
i.e. liberate free radicals, may vbe either unstable com
possibility of undesirable multiple reactions on a single
pounds which decompose under the reaction conditions
. molecule. Speci?c compounds which may preferably be
- used are toluene and isopropylbenze-ne (i.e. cumene),
however, other substituted compounds as above described
may also be used such as ethylbenzene, n-propylbenzene,
n-octylbenzene, etc.
The products obtained in the present process are of
the particular indane or substituted indane and a liquid
mixture of alkyl benzene compounds. These alkyl ben
zene side products boil over a narrow range determined
of course by the number of carbon atoms in the alkyl
chain of the starting material alkyl benzene. The pro
posed mechanism for the reaction of the present inven
tion to form indanes are:
(1)
Radical
R- + @011. _+ an + Gem
(2)
O-Om- + CH2=CH2 .__> @omomon,
such as peroxide materials, persulfates, etc. or physical
means for producing free radicals such as ionizing radia
tion, e.g. obtained from a Van de Graaif accelerator or
a nuclear energy source, such as a cobalt 60 source.
Examples of the unstable compounds which may be
utilized are hydrogen peroxide; hydroperoxides, having
no elements other than carbon, hydrogen and oxygen-in
the molecule, e.g. cumene hydroperoxide, tetralin hydro
peroxide, toluene hydroperoxide, tertiary butyl hydro
peroxide, the crude hydroperoxides obtained upon passing
air through hydrocarbons such as petroleum in liquid
phase and ‘alkyl peroxides, e.g. di-tertiary butyl peroxide.
Other peroxy catalysts which are stable, or only slowly
decompose, below about-100° C. can also be used, e.g.
benzoyl Peroxide, di-tertiary butyl peroxide, bis-Z-phenyl
propyl-peroxide-Z, alkali metal salts of persulfuric
acid, etc.
With respect to available physical means for initiating
70
the reaction, such sources as cobalt 60 sources, Van de
Graafr" accelerators, and atomic piles may be used. The
3,082,267
3
advantages for these sources, of course, is that they are
more economical.
In the case Where reaction is initiated with a peroxide
or hydroperoxide, the initiator is preferably added as a
series of increments at intervals throughout the course of
the reaction.
The present invention will be more clearly understood
from a consideration of the following examples.
Example 1
69 mol percent toluene and 31 mol percent ethylene
4
1.46 g. cumene hydroperoxide per liter toluene
90 mol percent toluene
10 mol percent ethylene
3 moles benzene diluent per mole toluene
Over 30 wt. percent indanes will be obtained
Remainder alkyl benzenes
It is to be understood that this invention is not limited
to the speci?c examples, which have been offered merely
as illustrations, and that modi?cations may be made with
10 out departing from the spirit of this invention.
What is claimed is:
were mixed in an autoclave at 250° C. and 1000 p.s.i.g.
1. An improved process for preparing indanes which
To this mixture was added 1.46 g. of cumene hydroper
comprises reacting an alkyl benzene having an alkyl
oxide per liter of toluene in 10 equal increments at 15
group containing not more than 10 carbon atoms, said
minute intervals. Reaction conditions were held for a 15
alkyl group having at least one hydrogen atom attached
total of 5 hours.
to a saturated carbon atom alpha to the benzene ring,
Mass spectrographic analysis of the product boiling
with 2-20 mol percent of ethylene at temperatures of
200 to 350° C., pressures of 400 to 800 p.s.i.g., and in
the presence of a free radical initiator, and recovering
20 indanes from the reaction mixture.
91 wt. percent alkyl benzenes
Further it was found that the yield of this product was
2. The process of claim 1 in which the alkyl benzene
26 weights per weight of initiator used.
is diluted with about 1 to 4 moles of benzene per mol
above toluene gave a weighted average of:
9 wt. percent indanes
of alkyl benzene.
3. An improved process for preparing indanes which
A reaction was carried out similarly to Example 1 under 25 comprises reacting in the presence of a peroxy catalyst
the following conditions.
having no elements other than carbon, hydrogen and
oxygen in the molecule and which is substantially stable
250° C.
below 100° C., an alkyl benzene having an alkyl group
1500 p.s.i.g.
containing not more than 10 carbon atoms, said alkyl
1.46 g. cumene hydroperoxide per liter toluene
30 group having at least one hydrogen atom attached to a
87.5 mol percent toluene
saturated carbon atom alpha to the benzene ring and
12.5 mol percent ethylene, reaction time 1 hour.
2-20 mol percent of ethylene at temperatures of 200 to
The product boiling above toluene was analyzed by
350° C., pressures of 400 to 800 p.s.i.g., and recovering
Example 2
mass spectrometer and was found to contain 16 wt. per
from the reaction mixture.
cent indane and 84 wt. percent alkyl benzene. The yield 35 indanes
4. The process of claim 3 in which the alkyl benzene
was 10 weights of material boiling above toluene per
is diluted with about 1 to 4 moles of benzene per mol of
weight initiator.
The improvement in yields of indanes obtained by.
alkyl benzene.
5. The process of claim 3 in which the amount of
utilizing less than 20 mol percent of ethylene may be
peroxy catalyst is about 0.1 to 5 wt. percent based on
40
seen from the accompanying drawing depicting a plot of
the alkyl benzene reactant.
weight percent indane yield vs. mole percent of ethylene
6. The process of claim 3 wherein the alkyl benzene
based on toluene in the system. Thus it can be seen that
reactant is toluene and the catalyst is cumene hydroper
extremely low ethylene concentrations result in large in
oxide.
creases in the yields of indanes obtained.
7. The process of claim 3 in which the alkyl benzene
Additionally for comparison purposes a run was made
reactant is cumene and the catalyst is cumene hydroper
wherein no ethylene was added to the reactor. Thus a
oxide.
one liter stirred autoclave was charged with 250‘ mls. of
8. The process of claim 3 in which alkyl benzene by
n-propylbenzene. The autoclave was heated to 250° C.
products from the reaction are recycled to the process.
and 1.46 g. cumene hydroperoxide diluted to 20 cc. with
9. An improved process for preparing indanes which
n-propylbenzene was added as the initiator solution. This '
comprises reacting, in the presence of a peroxy catalyst
solution was added in ten 2 cc. portions at 15 minute
having no elements other than carbon, hydrogen and oxy
intervals holding the reactor temperature constant at 250°
gen, an alkyl benzene having an alkyl group containing
C. Following completion of the reaction the bomb was
not more than 10 carbon atoms, said alkyl group having
cooled and held overnight. The product was then trans
at least one hydrogen atom attached to a saturated carbon
ferred to a still pot and most of the n-propylbenzene dis
atom alpha to the benzene ring, 1 to 4 moles of benzene
tilled 01f, leaving 8.8 grams of bottoms in the pot. The
per mole of alkyl benzene, and 5-15 mol percent of ethyl
bottoms were ?ltered and analyzed by mass spectrometer
and gas chromatographic equipment. Both analyses
showed the bottoms to be predominantly C9 aromatics
with no more than unmeasurable traces of indane struc
tures present.
From this data it can be seen that preparation of in
danes occurs by a true addition or telomerization reaction
rather than by simple cyclization.
Example 3
As Example 2 above but cumene was used in place of
toluene. Product contained about 1020 wt. percent
ene based on the alkyl benzene at temperatures of 250
to 300° C. and pressures of 500 to 700 p.s.i.g., the amount
60 of said catalyst being 0.1 to 5 wt. percent based on the
alkyl benzene reactant; and recovering indanes from the
reaction mixture.
10. An improved process for preparing indan which
comprises reacting toluene diluted with 1 to 4 moles of
benzene per mol of toluene with 5-15 mol percent of
ethylene i nthe presence of 0.1 to 5 wt. percent of cumene
hydroperoxide catalyst based on toluene, at temperatures
of 250° to 300° C. and pressures of 500 to 700 p.s.i.g.
and recovering indan from the reaction mixture. 4
methyl substituted indanes.
70
Example 4
References Cited in the ?le of this patent
Utilizing a procedure similar to that used in Example 1
UNITED STATES PATENTS
toluene and ethylene are reacted as follows:
300° C.
500 p.s.i.g.
2,660,610
2,748,178
Erchak, Jr ____________ __ Nov. 24, 1953
Pines et al ____________ .. May 29, 1956
1
l
l
I
Документ
Категория
Без категории
Просмотров
0
Размер файла
356 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа