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4 ‘2,398,685
Patented Apr. 16, 1946
‘UNITED ‘Sm-Es PATENT‘ OFFICE
_
2,898,685
PRODUCTION OF AGYCLIC KETONES
,
'
~Harry Louis Yale and George W. Hearne,
Berkeley, Calif., asaignors to Shell Development .
,Company, San Francisco, Calii'., a corporation
of Delaware
No Drawing. Application January 29, 1944,‘
Serial No. 520,340‘
_
‘
12 Claims. . (01. 260-597) ‘
stage operation. In the single-stage mode of ‘ _
operation, the ole?n may be' reacted ‘with the
This invention relates to the production of
, acyclic ketones from ole?ns. More particularly,
oxygen-containing mercuric salt under condi- Y
the invention relates to a method for preparing
acyclic ketones which comprises reacting a non
tertiary ole?n containing more than three carbon -
tions such that the ‘ole?n-mercuric salt complex
is decomposed to form a ketone and a mercurous
atoms with an oxygen-containing mercuric salt.
It has been found that non-tertiary acyclic
may be accomplished, for example, by carrying
salt substantially as soon as it is formed. This
out the reaction at a temperature which’ is at or
ole?ns having more than three carbon atoms may
be converted economically and in good yields to
above the decomposition temperature of the ‘said
‘ole?n-mercuric salt complex. In this ‘embodi
ment of the invention a quantityof ole?n may-be
ketones, including the hitherto relatively unavail
able vinyl-type ketones
.
passed into or contacted with a solution of an
(RE-CH=CH:)
' '
oxygen-containing mercuric salt contained in a _
suitable reaction chamber at a temperature which
which are useful as solvents and in a wide variety 15 is approximately-the boiling or re?ux tempera- '
ture of the said solution, the ketone product being
separated by suitable means from the gases leav
> said ole?nsiby treatment with an oxygen-con
taining mercuric salt. The nature of the reaction
ing the said reaction chamber. Better yields and‘
which occurs is dependent upon the type of ole?n
a superior product are obtained in most cases,
employed as a starting material. When an alpha 20 however, when the process is carried out in two
stages. When employing the two-stage mode of
ole?n of the type described is reacted with an
operation, a quantity of ole?n or of ole?n-con
oxygen-containing mercuric salt, the ole?n is
converted to the vinyl-type ketone of correspond
taming gas may be contacted with a neutral or
acid solution of an oxygen-containing mercuric
ing structure. However, when an ole?n is used
compound contained in a suitable reaction ves
in which the carbon-carbon double bond does not
of other industrial applications, by oxidizing the
involve a terminal carbon atom, as in a beta
‘ sel, the temperature being maintained at a level
olenn, a saturated ketone is produced. These re
actions may be represented by the following equa
which‘is substantially below the decomposition
tions in which alpha-butylene and beta-butylene
named as representative ole?ns:
,
.
so
temperature of the ole?n-mercuric compound
complex. When the desired amount of the said
oxygen-containing mercuric compound has beenv
. convertedv to the complex, an oxygen-containing
acid may be added, if desired, and the tempera
ture of the reaction mixture raised to a tempera
cnigon=cni+2ngisol+zmsol '
and
-
CHaCH=CHCHs+2HgBOc+HsO 'o—-*
him which is above the decomposition tempera- _
35 ture of the complex, thereby e?ecting its decom
cmgcnionwnisowngiso,
position and forming a ketone and a quantity of
an oxygen-containing mercurous compound.
The ketone product may then be separated from Y
Although the above represent the net reactions 4 the reaction mixture by any desired means, as-by
, occurring'when a normal butylene is treated with 40 distillation.
-
The above-described procedure maybe carried
a reagent comprising mercuric sulfate and water
under suitable conditions of operation, it appears 7 out in a batch, intermittent or continuous man
ner. when a batch operation is desired the ole?n
that the reaction occurs in two steps, in the ?rst
may be added to the oxygen-containing mercuric
' ‘of which the mercuric sulfate reacts with the
butylene to form a butylene-mercuric sulfate 45 compound contained in a suitable reaction ves- ‘
sel in substantially the same fashion as described
complex. This complex is then broken down
under the conditions of the reaction to form a
ketone, sulfuric acid and mercurous sulfate. vIin
the‘ case of beta-butylene, the reactions for these "
‘steps may be represented as follows: _'
above. when operating as a continuous process,
however, a stream of ole?n or of ole?n-containing
gas may be continuously passed concurrently or
countercurrently to a stream of the ongen-con
taining-mercuric-salt reagent in'a suitable re
action chamber or absorption tower. In single
stage operation the reaction may be carried out
in the presence oi an oxygen-containing
acid and
_ It'is therefore possible to'carry out the process of
l
g the invention as either a single-stage or a two- ,5‘ ate. temperature which is. suiiiciently high to '
a
8,898,685
e?'ect the decomposition of the olefin-mercuric
heptadienes and the like. These compounds
salt complex substantially as soon as it is formed.
_may be substituted with non-interfering sub
stituent groups such as the ether, halogen,
hydroxyl, carbonyl and ester groups. The ole
The ketone product may then be continuously
withdrawn from the reactor and purified by dis.
tillation, While the mercurous compound which
?ns may be used singly or in combination
is formed together with the ketone by-the'de
with each other. They may be used as pure
composition of the said complex may be contin
one?ns or in
admixture with non-interfer
uously withdrawn as a sludge, separated from the.
ing substances, e. g. the paraffin hydrocarbons,
acid, decomposition products, etc.,'with which it
. nitrogen, etc. The process is thus adapted to the
may be contaminated and reconverted by suitable 10 utilization of commercial ole?n fractions con
means to the oxygen-containing mercuric com
taining in addition to ole?ns substantial amounts
pound which is used as a starting material. The '
mercuric compound as well as any ‘unreacted
ole?n which may be recovered'from the reaction
of paramn hydrocarbons and, in some cases, ni
trogen.
'
The structure of the product formed is de- -
chamber may be added to the fresh feed and 35 pendent upon the nature of the ole?n used. In
recycled.
_
-
"
‘
When carrying out the reaction continue
in two stages, the vole?n may be continuously
. general alpha-type ole?ns (RCH2CH=CH2) yield
vinyl ketones
contacted with the mercuric salts-containing re
’
RCCH=CH2
agent at a temperature at which the ole?n-mer 80
curic salt complex‘ is stable. This step may be
together with small amounts of saturated di
ketones
carried out with’ or without the addition of oxy
(i
gen-containing acid. The mixture containing
' )
(Rb-L0H.)
I
or ‘o '
"the ole?n-mercuric salt complex may then be
passed continuously into a second reactor where 26
while other non-tertiary 'ole?ns yield either one A
an acid may be added, ‘if desired, and the decom
position of the complex effected by heating the
or both of two ketones of isomeric structure de
mixture to a temperature which is equal to or
pending upon the operating conditions. Thus,
greater than the decomposition temperature of
an ole?n having the structure RCH=CHCI-h
the said complex. The resulting ketone and 80 when treated with a mercuric salt in accordance
mercurous-salt-contalning sludge maybe sepa
with the process of the present invention may
yield either
'
'
‘
rately withdrawn from the reaction chamber and
recovered as indicated hereinabove.
A preferred method of executing the process
of the invention may be illustrated by that which
may be employed in omdizing beta-butylene to
- methyl ‘ethyl ketone. In accordance with this
O
O
' apicmcm or ,Romgom
or a mixture of these two isomers. .
A variety of mercuric salts may be used in exe
cuting the process of the present invention.
Suitable salts comprise in general the mercuric
furic acid and‘mercuric sulfate at ‘a temperature 60 ‘salts of the oxygen-containing acids such as sul
of about 20° C. to about 70° (2., but preferably
furic acid, acetic acid, nitric acid, phosphoric
between about 50° C. and about 60° C. and at '
acid and the like. Mercuric sulfatc'represents a
such a rate that the beta-butylene is substan
preferred member of this group, although mer
tially completely absorbed. When the mercuric
curic nitrate, mercuric phosphate, mercuric ace
sulfate content of the solution has been substan 45 tate, mercuric formate, mercuric propionate,
tially completely converted to the beta-butylene
mercuric chloro acetate, etc.,'may also be used.
mercuric sulfate complex, as indicated by the
These salts may be used singly or in combination
characteristic color change of. the solution and by
with each other. If desired, they may be pre
the failure of the solution to absorb further
pared insitu by adding an acid to an appropriate
.quantities of beta-butylene, the temperature of 50 mercuric salt such as mercuric oxide or mercuric
the reactionmixture is increased to about 100°
carbonate, thereby converting the said compound
C., thereby effecting the decomposition of the
to the‘ desired salt. The amount of mercuric salt
olefin=mercuric~ sulfate complex and forming
to be used is dependent upon the amount of ole
methyl ethylyjketone and mercurous sulfate.
?n which it is desired to convert to the corre
The methyl ethyl lretone may then be separated 55, sponding ketone. In general, it is preferable to
from the mixture by any suitable means, as by
use an amount of mercuric salt which represents
manner of operation a stream of .beta-butylene
may be contacted with a mixture of aqueous sul
distillation.
'
,
.
>
The process of the invention may be applied
with suitable modi?cations to the oxidation of
an excess of from about 25% to about 50% over
that theoretically required to combine with the
olefin. As indicated hereinabove, the mercuric
a wide variety of ole?ns. Suitable ole?ns are 60 salt is converted during the course of the reac
tion to the corresponding mercurous salt which
more than there carbon atoms. Representative
is recovered \as a sludge from the reaction mix
ole?nswhich may be converted to the corre
ture. The mercurous salt content of the said
sponding ketones by the process of theinvention
sludge may be converted to the mercuric salt by
are, for - example, :alpha-butylene (butene-l), 65 any one of several methods known heretofore to
beta-butylene ,(butene-Z) ,. pentene-l, pentene-2,
the prior art. The mercurous salt may be con
> hexene-l, hexene-2, hexene-3, i-methylwpen
verted to the corresponding mercuric salt, for
in generarnon-tertiary acyclic ole?ns having.
tone-‘l, 4'-methyl-pentene-2, 3-methyl-butene-l,
3-methyl-pentene-l,,4-methyl-hexene-l, li-ethyl
hexane-‘o1, 4.-methyl hexene-2, 4-ethyl-hexene-2,
3,-methyl-hexene-l, a-ethyl-hexene-l, S-methyl
hexane-'1, 5-methyl-7hexene-2, 5-methyl-hexene
3, the no
_ octenes, th
' tiary~ heptenes, the non-tertiary
nonetertiary nonenes and decenes,
buta'diéneftbe'pentadienes, the hcxadienes, the
example, by electrolytic oxidation, by heating
‘ with nitric acid, by treating with chlorine gas
70 in the presence of acid, etc. The re-oxidized
mercuric salt may then be used to convert a fresh
quantity of ole?n to ketone.
Although as indicated hereinabove the process
of the invention may usually be executed without
76 the addition of an acid to the reaction mixture,
.
it may be desirable in some cases to carry out the
reactions, particularly .the decomposition of- the
ole?n-mercuric salt addition compound, in a‘ re
.
3
eflectively executed at atmospheric pressure. 11
7desired, however, subatmospheric orsuperatmos- .
pheric pressures may be employed. Operating at
elevated pressures, i. e‘. pressures of between about
50 lbs. per sq. in. and about 300 lbs. per sq. in.,
action medium to which an acid has been added.
If an acid is used, it should be an'oxygen-con
_ taining acid of suflicient strength to prevent the '
may be advantageous in some instances, as where
_ phosphoric acid or, in general, any organic or
type of apparatus which is adapted'to batch or
continuous one-stage or two-stage operation and
it is desired to effect the complete and rapid ab
hydrolysis of the mercuric salt and to eii'ect the
sorption in the mercuric salt reagent of a par
decomposition of the ole?n-mercuric salt com
ticular ole?n which is in the gaseous state at the
plex under the conditions of the reaction. Suit
able acids are the relatively strong oxygen-con 10 temperature of reaction.
‘ The process. may be carried out in any suitable
taining mineral acids such as sulfuric, nitric, or
inorganic oxygen-containing acid of su?lcient
which is provided with suitable means for main
talning the reaction mixture at the desired tem-
strength to result in the formation of a reaction '
medium having a pH of less than about 4. 1 Such
perature level. The equipment should be of such
a nature as to effect intimate contact between the
ole?n and the mercuric salt reagent. This may
acids include acetic acid, bromacetic. acid, butyric
acid, chloracetic acid, citric acid, formic acid, iso
butyric acid, oxalic acid, phosphoric acid, phos
phorous acid, propionic acid, sulfanilic acid, sul
be accomplished in batch operation by bubbling
furous acid, valeric acid and the like. These acids 20 a quantity. of the gaseous ole?n through the said
reagent and in continuous operation by passing
may be used singlyT or in combination with each
a stream of the ole?n concurrently or, counter
other and may or may not correspond to the .
currently to a stream of the said mercuric salt
‘ mercuric salt used. The acid may. if desired, be
introduced as the acid anhydride and converted ‘ , reagent in a suitable absorption tower.
to the corresponding acid by reacting it with the 25 The ketone product may be separated from the
reaction‘ mixture in any desired manner as by
water- content of the mixture. In many cases,
- distilling " it‘ together with relatively small
sulfuric acid in a concentration ofirom about
amounts of water or solvent and subsequently‘
0.1% to about 25.0%, preferably about 0.25% to
separating the ‘desired ketone from the contami
- about 5.0% represents a particularly desirable
acid medium in which to carry out the process of 80 nating materials by any suitable. means vas by
fractional distillation, .salting out, etc. The mer
I the invention.
curous salt, which is usuallycontaminated with
small amounts of free mercury, may be with
It is generally preferred to carry out the re
7 action in aqueous medium. However, if desirable
drawn as a sludgefrom the reaction vessel. The
mercurous salt may then be ‘converted to the
desired mercuric salt as indicated hereinabove.
or necessary because of the nature of the reac
tants used a mutual solvent, e. g. acetone, may
be added to promote the solution or absorption
of the ole?n in the reaction mixture. Suitable
The process of the invention is illustrated by
the following examples, wherein the amounts of _
solvents are those which will not cause deleteri
ous side reactions to take place and which may
the reactants are given in parts by weight.
be readily separated from the reaction products.
'
The temperature at which the process is car
Example 1
A stream of beta-butylene (butene-2)
ried out is variable depending upon the nature of
was ‘
passed into a stirred suspension comprising about
5
of mercuricsulfate and about 22 parts
u the reactants, and upon whether the process is
carried out in one or two stages. If vcarried out
or a 1.8% aqueous solution oi’ sulfuric acid at such
as a single-stage process, i. e; one in which the 45 a rate thatthe absorption of the beta-butylene
ole?n-mercuric salt complexis decomposed sub
was substantially complete, the temperature be
stantially as
n as formed, the temperature em
ployed may advantageously be a temperature _ ing maintained at about 55° 0. As the gas was
absorbed, theoriginal yellow color of the suspen
sion slowly changed to white‘. when the suspen
sion had become uniformly white in color, the
which is approximately the boiling temperature
of the reaction mixture. Where the reaction is
carried out in aqueous medium at atmospheric
pressure, this temperature will be about 100° C.
Where, however, the process is carried out in two
stages, the temperature of operation of the ?rst '
stage, _i. erthat stage in which'the cloth: is re
temperature was slowly raised to 100° 0. Decom
position of the beta-butylene-mercuric sulfate
complex'occurred at this temperature and the
methyl ethyl ketone distilled out of the reaction
mixture as the water-methyl ethyl ketone azeo
acted with the mercuric ‘salt to form an ole?n
mercuric salt complex, should be substantially be- '
trope. Additionpf salt to this distillate resulted '
in the separation .of the methyl ethyl ketone
low the decomposition temperature of the. said >
complex. with most ole?ns a temperature-range
of between about 20° 0. and about 70° 0., prefer
ably between about 50° 0. and about 60° 0., rep
’ resents a suitable temperature range. After the‘
conversion of the ole?n to the ole?n-mercuric salt
‘complex is substantially complete, the tempera
-
product.
'
Example II
A quantity of beta-butylene was reacted-with
a mixture comprising about 1 part of mercuric
acetate and about 4 parts of a 2.84% aqueous so- '
luti'on‘ of acetic acid substantially as described‘in
Example I. Distillation of the reaction product
ture may be raised in the second stage of the
process to a level at, which the said complex is . - resulted in the separation'of methyl ethyl ketone
together with a small amount of acetaldehyde. 1
unstable and decomposes to form the desired ke
tone together with a quantity of mercurous salt. __
Example, 111
This is in general a temperature of between about
90° 0._ and about 105° 0., preferably a tempera 70 Beta-butylene was reacted with a sulfuric ac
solution oi mercuric acetate using the procedure
.ture which is approximately equal to the reflux
.or boiling temperature of the reaction mixture, ’ described in Example I. The product, i. e. the
methyl ethyl ketone, was distilled from the re
e. g. a temperature of, about 1100' 0., when the re- '
action mixture as the ‘water-methyl ethyl vketone
action is carried out in aqueous medium. 2
WW'OPB‘
'
'
'
f
The process of the invention may usually be
sea
ethyl iretone which comprises.forming aninter
,
Beta=buty1ene was reacted with an aqueous ni
tric acid solution of mercuric nitrate substantial»
ly in the manner described in Example I. The
reaction in this case gave approximately equal
amounts of methyl ethyl ,ketone and diacetyl to
gether with a small amount of acetaldehyde.
ing the said butene-2 at a temperature of be
tween about 50° C. and about 60° C. with men
curic sulfate in an aqueous acid medium con
taining from about ‘0.5% to about 5.0% of sul
furic acid and subsequently heating the acid mix
ture containing the said complex to a tempera
ture of about 100° 0., thereby effecting its de
‘ Example V
Pentene-2 was reacted with an aqueous sulfuric
acid solution of mercuric sulfate in the manner
described in Example I. In this case a mixture
of methyl-n-propyl ketone and di-ethyi ketone
was separated from the product distilling from
the reaction-vessel.
mediate mercury-containing compound by react
‘
composition and forming the desired methyl eth
yl ketone.
3. A process for the production of methyl ethyl
ketone which comprises contacting at a tempera
ture of between about/i0" C. and about ‘20° C. '
beta-butylene with a quantity of a reagent com
Example VI
prising mercuric sulfate and dilute sulfuric acid
But'adiene was reacted with an aqueous sulfuric
acid solution of mercuric sulfate as described in
furic acid thereby forming ‘a butylene-mercuric
sulfate addition compound, and subsequently
containing between about 0.5% and 5.0% of sui
Example I to give methyl vinyl ketone together 20 heating the said addition compound in an acid
with small amounts of diacetyl as reaction prod
ucts.
_
Example W1‘
A mixture of about 14 parts of hexane-l. and
about 65 parts of a 1.74% aqueous solution of
sulfuric acid was heated to a temperature of
about 55° C. until the formation of the hexene-l
mercuric sulfate addition product was substan‘
medium at a temperature sufficiently high to ef
fect ‘the decomposition of the said addition com
_ pound and the formation of the desired methyl
ethyl ketone.
‘
a. A process for the production of methyl vinyl
ketone which comprises forming a. butylene-mer
ouric sulfate complex by contacting alpha-bu
ty’lene with a quantity of mercuric sulfate in an
aqueous acid medium containing from about 0.5%
product at 100° C. resulted in the separation of 30 to about 5.0% of sulfuric acid at a temperature of
tially complete. Decomposition of the addition
propyl vinyl ketone together with'a small amount
of acetyl, butyryl.
Example VIII
between about 50° C. and about 60° C., subse
quently decomposing the said complex and form
ing the desired ketonc by heating the said com
plex in the said aqueous acid medium at a tem
Oxidation of octane-1 under conditions similar 35 perature which is substantially equal to the boil
to those described in Example VH resulted in the
ing temperature of the latter. '
'
recovery of pentyl vinyl ketone and acetyl hexoyl.
Example IX
5. A process for the production of methyl vinyl
ketone which comprises reacting butene-l at a
temperature of between about 40° C. and about
Butene-l was passed into a sulfuric acid solu=
70° C. with a mixture of mercuric sulfate and di
tion of mercuric sulfate maintained at a temper
lute sulfuric acid containing from about 0.5%
ature of about 55° ‘C. until- the absorption of the
and 5.0% of sulfuric acid, thereby forming a
butene and the formation of the butene-mercuric
butene=mercuric sulfate addition product, and
sulfate addition compound were substantially
subsequently heating the said addition product in .
complete. The temperature of the reaction mix 45 the said acid solution to a temperature of about
ture was then raised to about 100° C. in order to
100° C. in order to decompose the said addition
decompose the addition compound and form
methyl vinyl ketone.
Example X
A stream of beta-butylene was passed into a
mixture‘ comprising about four parts of water
and one part of mercuric acetate, no added acid
being present. When absorption of the beta-bu
tylene was complete, the temperature of the mix
turewas increased to 100° C., thereby hydrolyz
ing the beta-butylene-mercuric acetate complex.
~ Methyl ethyl ketone was separated as a product
from the reaction ‘mixture.
product and form the desired methyl vinyl ke
tone.
‘
~
~
6. A process for the productionof methyl vinyl
ketone which comprises oxidizing beta-butylene
with a mixture comprising an oxygen-containing
mercuric salt and an acid solution having a sul
furic acid content of from about 0.5% to 5.0%.
7. A. process for the production of methyl vinyl
55 ketone fromalpha-butylene which comprises con
tacting the said alpha-'butylene at a reaction tem_
perature with an oxidizing mixture comprising an
oxygen-containing mercuric salt in a solution of
sulfuric acid having a sulfuric acid content of
We claim as our invention:
60 from about 0.5% to 5.0%.
,
1. A process for the production or methyl ethyl ’
8. A process for preparing acyclic monoketones
ketone from butene-i2 which comprises reacting
at a‘ temperature of between about 50° C. and
' about 60° C. the said butene-2 with mercuric ace“
A from a normal butylene which comprises react
ing the butylene at a reaction temperature with
an oxygen-containing mercuric salt in an aque
tate in an acid medium which contains between 65 ous solution of sulfuric acid having a sulfuric
about 0.5% and about 5.0% of sulfuric acid there
acid concentration of from 0.5% to 5%.
by forming an addition product between the said
butene-Z‘ and the mercuric compounds present in
the said acid medium, and subsequently raising
r 9. A process for producing acyclic monoketones
which comprises oxidizing an acyclic ole?ne hav
ing more than three carbon atoms and containing
' the temperature of the said acid medium to a 70 only one unsaturated linkage consisting of a dou
' temperature which is approximately its boiling
ble bond between two carbon‘ atoms ‘each having
temperature in order to effect the decomposition
at least one hydrogen atom directly attached
of the said complex and the formation of methyl
thereto, witha mixture comprising an oxygen
ethyl ketone.
‘
containing mercuric salt andlgan aqueous solution
2. A process for oxidizing butcher-2 to methyl 75 of an unison-containing acid having an acid
.
5
9,898,685
‘ strength correspondingtothatoi' anaqueousso
lutlon of sulfuric acid having a sulfuric acid'con
centration of 0.5% to 5%.
10. A process for the production of an aliphatic
monoketone which comprises maintaining an 5
aqueous acidic mixture oi’ a mercuric salt at a‘
temperature in the range of 40° C. to 70° 0., add
ing an open-chain olefin having more than three
sisting of a double bond‘ between two carbon -
atoms each having at least one hydrogen atom
directly attached thereto, with an aqueous acidic
mixture of a. mercury salt in such proportion '
that thevmercury salt is present in an amount
corresponding to a 25% to 50% excess over the
amount theoretically required to react with all
of the olefin.
‘
'
two carbon atoms each having at least one hy
‘ 12. A_ process for the production or propyl vinyl
ketone which comprises reacting hexene-l at a
temperature of between about 50° C. and about
drogen atom directly attached thereto, to said
60° C. with a quantity of mercuric sulfate in an
carbon atoms and containing only one unsatu- ‘
rated linkage consisting of a double ‘bond between‘
aqueous mercury salt solution in an amount ni
su?icient to combine withall or the mercury salt.
-then raising the temperature of reactionto about
a 100° C. and recovering an aliphatic ketone from
the reaction'mixture.
/
.
11. A process for the production of an aliphatic
monoketone which comprises reacting an open
chain ole?n having more than three carbon atoms
and containing" only one unsaturated linkage con
aqueous acid medium containing from about 0.5%
to about 5.0% of sulfuric acid, thereby forming
a hexene-l-mercuric sulfate addition product,
and subsequently heating the said addition prod
uct in the said acid solution to a temperature of
about 100° C. to decompose the said addition
product and form the desired propyl vinyl ketone.
,
:
HARRY LOUIS YALE.
GEORGE W. HEARNE.
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