Preliminary investigation of caronic acid esters
by Tom Ting Charng
A thesis submitted to the Graduate Faculty in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE in Chemical Engineering
Montana State University
© Copyright by Tom Ting Charng (1969)
Abstract:
The present potential supply of delta-3-carene, a bicyclic terpene, in the by-product turpentine
produced by five western Kraft pulp mills, is more than 1,000 gallons per day.
Two esters of cyclopropane ring-containing dibasic acids (caronic and homocaronic acids) were
recovered from the mixture of oxidation products obtained by the potassium permanganate oxidation of
delta-3-carene in acetone. The yield of di-butyl caronate and di-butyl homocaronate, based on 41.4
grams of delta-3-carene, was 27.3& and 18.2%, respectively.
The identification of di-butyl caronate and homocaronate was based on gas chromatography and
infrared spectroscopy.
Delta-3-carene, 4l.4 grams, was oxidized with 260 grams potassium permanganate in 2,000 ml. of
acetone at a temperature of 12.5 - 14.5 °C.
The potassium permanganate reacted completely in five hours. Ninety-seven percent of the oxidation
products were adsorbed on the surface of the manganese dioxide formed during the reaction. The
oxidation products were removed from the manganese dioxide surface with 85% efficiency by washing
with hot water.
The aqueous solution of oxidation products was acidified with hydrochloric acid and extracted with
ethyl ether. The water phase was extracted again after concentration. The step was repeated three times.
Most of the inorganic salts were removed after each concentration.
The water layer, about 80 ml, was mixed with the ether extract.
250 ml. of 1-butanol and 200 ml. of toluene were added. The mixture was subject to total reflux for
five hours, after which the crude ester was mixed with 30% ammonium hydroxide and followed with
hot water. The water was removed by azeotropic distillation with toluene, an entrainer. The vacuum
distillation technique was also applied to prevent the unreacted acid from decomposing at the high
temperature. PRELIMINARY INVESTIGATION OF CARONIC ACID ESTERS
by
TOM TING CHARNG
A thesis submitted to the Graduate Faculty in partial
fulfillment of the requirements for the degree
of
MASTER OF SCIENCE
■.in':
•Chemical Engineering
Approved:
■MONTANA STATE UNIVERSITY
Bozeman, M o n t a n a '
M a r c h , 19 69:
I
iii
ACKNOWLEDGMENT
The author wishes to thank the entire staff of the Chemical
Engineering Department of Montana State University for their suggestions
which led to the completion of this research p roject.
Particular thanks
is given to Dr. Lloyd Berg who was the author's research director and
major pr o f e s s o r ..
The author thanks Mr. James Tillery and Mr. Silas Huso
for their help in equipment fabrication and maintenance.
due to Mrs. Joan Hall for typing the final manuscript.
T h a n k s .are also
iv
' TABLE OF COffTEM1S
Page
ABSTRACT .......................................■................... Vii
• I.
INTRODUCTION ......................... ...................... .
..
I
A.
.
I
D e l t a - S - C a r e n e .................. ■...................... ..
B. ' Oxidation of Delta-S-Carene
III.
2
C.
Esterification of Oxidation Products of Delta-S-Carene
D.
Potential Utilization of Esters of Cyclopropane Ring-'-.
Containing Dicarboxylic Acids from Delta-S-Carene
...
2
Incentive for Esterification of Caronic Acids Research .
3
E.
II.'
............. ..
.
2
RESEARCH O B J E C T I V E S .................. ' . ......................
4'
EXPERIMENTAL D A T A ........... ' ......... ‘ ........... . . . . .
5
■A.
Preparing the Caronic Acids for Esterification . . . . . .
5
I..
6
■2.
3.
B.
• C.
Equipment
.........................................
6
The Ratio, ofR a w - M a t e r i a l s ............................
M e t h o d ...................
.
6
E s t e r i f i c a t i o n ........................... •.................
Tr
1.
E q u i p m e n t ...................................
8
2.
Method
3.
Neutralization . . ■....................................■
4.
Purification .■................................ .
Gas
. . . ..................... ..
Chromatography .............
. . ..............
. . .
. . . . .
.9
9
10
10
1.
Analysis of Esterification P r o d u c t s ................"
10
2.
Analysis Techniques
11
.................................
V
TABLE OF COMTEHTS (continued)
IT.
D.
pH M e a s u r e m e n t ........................... , .............
12
E.
S p e c t r o s c o p y ...............................................
13
F.
Manual Integration.Techniques for Calculation of Yield
Through Chromatographic P e a k s ..............................
13 .
Identification of P r o d u c t s ............................
. B i -Butyl Caronate-
........................................
Di-Butyl Homocaronate
B.
TI.
15
DISCUSSIOM OF R E S U L T S ................
A.
V.
' page
.'.................. ■ ........... ■ .
Calculation of Conversion Percentage
CONCLUSIONS
•........................... '
. . . . . . . . . .
'...........
1515
15
l6
17
................................................
18
APPENDIX . . ....................................................
19
LITERATURE CITED . . ....................... ' ..................
3U
RECOMMENDATIONS
vi
LIST OF FIGURES
Page
Figure I.
The Structure, of Delta-3-Carene
. . . . . . . . . . . . .
20
Figure 2.
Cyclopropane Ring-Containing: Dicarhoxylic Acids Derived
From D e l t a - 3 - C a r e n e .................. .. ................
21
Figure 3.
Figure U .
Figure 5Figure
6.
Figure J.
Figure
8.
Esters Derived From Cyclopropane Ring-Containing
Dicarhoxylic Acids ..........................................
i
Apparatus for Potassium Permanganate- Oxidation,of
Delta-S-Carene in Acetone
.................................
Conversion % vs. the Amount of Oxidizing Agent
Vacuum Distillation System . . .
23
2h ■
. . . . .
............... ..
22.
. .
25
True-Boiling-Point Curve of I-Butanol-Caronic AcidsToluene S y s t e m ......................................
Sample Collection in Preparative Gas Chromatography
26
. .
Figure 9•
Gas Chromatogram of the Esterification- P r o d u c t ..........
Figure 10.
Gas Chromatogram of Di-Butyl Caronate
Figure 11.
Infrared Spectrum of the Di-Butyl Caronate from the
Mixture of Esterification- P r o d u c t ...................
27
28'
.....................
29
30
Figure 12.
Infrared Spectrum of Di-Butyl Cafonate ....................
31
Figure 13.
Infrared Spectrum of Di-Butyl Homocaronate ................
32
Figure lk .
Cox Chart for Various A z e o t r o p e s ............. .
...
.
33
vii
ABSTRACT
The present potential supply of delta-3-carene, a M c y c l i c terpene,
in the by-product turpentine produced by five western ICraft pulp m i l l s ,
is more than 1,000 gallons per day.
Two esters of cyclopropane ring-containing dibasic acids (caronic
and homocaronic a c i d s ) were recovered from the mixture o f ’oxidation
products obtained by the potassium permanganate oxidation of delta- 3-carene
in acetone.
The yield of di-butyl caronate and di-butyl homocaronate,
based on ill. U grams of delta- 3-carene, was 27.3& and 18.2%., respectively.
The identification of di-butyl caronate and homocaronate was based
on gas chromatography and infrared spectroscopy.
Delta-3-carene, 4l.H grams, was oxidized with 260 grams potassium
permanganate in 2,000 ml.of acetone at a temperature of 12.5 - lU.5 °C.
The potassium permanganate reacted completely in five h o u r s . Ninety-seven
percent of the oxidation products were adsorbed on the surface of the
manganese dioxide formed during the reaction.
The oxidation products
were removed from the manganese dioxide surface with 85% efficiency by
washing with hot water.
The aqueous solution of oxidation products was acidified with
hydrochloric acid and extracted with ethyl ether.
The water phase was
extracted again after concentration. ■ The step was repeated three times.
Most of the inorganic salts were removed after each concentration.
The water layer, about 80 ml, was mi x e d with the ether extract.
250 ml. of 1-butanol and 200 ml. of toluene were added.
The mixture was
subject to total reflux for five h o u r s , after which the crude ester was
mixed with 30% ammonium hydroxide and followed with hot water.
The water
was removed by azeotropic distillation with t oluene, an entrainer.
The
vacuum distillation technique was also applied to prevent the unreacted
acid from decomposing at the high temperature.
I.
INTRODUCTION
A.
Delta-S-Carene
The principal starting material in this research was delta-3-
carene which was produced in the laboratory at the Department of Chemical
Engineering, Montana State University'.
The structure is given in Figure I
Delta-3-carene is in the by-product turpentine produced by
five western Kraft pulp mills
2
in the United States and Canada.
three of them are presently condensing their turpentine
2
.
t)nly
The sources of
delta- 3-carene are summarized in Table I.
TABLE I .
Availability of Delta-3-Carene in the United States and Canada
A.
Mills producing and condensing delta-3-carene containing
turp e n t i n e :
Potlatch Forests, Incorporated, Lewiston, Idaho.
Hoerner-Waldorf Paper Products Company, Missoula, Montana.
Southwest Forest Industries, Snowflake, Arizona.
'B.
Mills producing but not condensing delta-3-carene containing
turp e n t i n e : '
Boise-Cascade Corporation, W a l l u l a , Washington.
Northwestern Pulp and P o w e r , L i m i t e d , Hinton, Alberta.
As indicated in Table I , three mills are presently producing and
condensing turpentine containing delta-3-carene.
The total turpentine
3
volume from these mills is more than 1,000 gallons per day .
There is no
known commercial use for delta- 3-carene up to now that would make its
recovery and purification economically attractive.
-2B.
Oxidation of Delta-3-Carene
The oxidation of delta-3-carene and subsequent- formation and
'
\
purification .-of dicarboxylic acids containing the cyclopropane -r-ing has
been reported previously in 'the l i t e r a t u r e . ^ ^
structures of these acids are shown in Figure 2.
■except the l a s t , appeared prior to 1930.
The names' and
All of the re p o r t s ,
None of these reports gave- '
indication of commercial development of the acids.
-
•.
C.
Esterification of Oxidation Products of Delta-3-Carene
No references have been made in the literature to either a
source of any of these esters or to an experimental work for analytical
purpose.
'
There are five possible combinations.of esters.of'caronic
acid .and homo caronic acid which are shown -in- Figure 3.
We were not able
to locate-a sample of instrumental analysis-of these esters from a ny
outside source..
D.
,
Potential Utilization of Esters of Cyclopropane Ring-Containing
■ - Dicarboxylic Acids from Delta-3-Carene
.„ .
Since-a convenient source of any of these esters has never
been available for new product r ese a r c h , it is not-surprising that
industrial uses have not been, reported.. . '■
. The esters of caronic acids should.be, like the.esters of .
most dicarboxylic acids such as adipic acid, effective plasticizers for
many polymeric m a t e r i a l s i n c l u d i n g polyvinyl 'chloride and its copolymers,
natural and synthetic r u b b e r s , p olystyrene, and cellulose derivatives.
I
-3These plasticizers are easily incorporated into the polymer "by the usual
m e t h o d s .^ ^ ^
They can also he converted to a higher ester by
transesterification as demanded.
These esters can he readily reconverted into, acids hy simple
hydrolysis in the presence of hydroxide ions, or converted into other
derivatives.
Dicarhoxylic acids have been used in the field of synthetic
p o l y m e r s , lubricants, coatings, elastomers and thermosetting compounds.
E.
11
Incentive for Esterification of Caronic Acids Research
The previous work on the oxidation of delta-3-carene proved
that it provided possibilities for a new industry located in Montana.
could produce cis-caronic acid in an excellent p u r i t y ,
99$ pure,
.nevertheless, the. yield was not substantial for commercialization.
We
II.-
RESEARCH OBJECTIVES
The overall- goals of this research were to p roduce-the esters of
cyclopropane ring-containing dicarhoxylic acids from delta- 3-carene, and
to report the yield.
1.
The research objectives were as follows:
Isolate and confirm the identity of the esters of caronic and
homo-caronic acids.
2.
Choose a suitable alcohol for a good yield of esterification.
3.
Produce esters from delta-3-carene oxidation products.
4.
Purify the esterification products.
5.
Report yield.
III.
EXPERIMENTAL DATA
A.
Preparing the Caronic Acids for .Esterification
Caronic -acids were prepared by potassium permanganate
oxidation of delta-3-carene in acetone p h a s e .
This oxidation reaction
12
was first reported in 1923 b y Simonsen and R a o .
The following reaction
system was used:
delta-3-carene
.'...................... ..
Ij-O .O grams
potassium p e r m a n g a n a t e ................
acetone
...............................
temperature
p6.0 grams
400.0 ml.
....................
0.0
6C-
After all the potassium permanganate had reacted, the MnOg was removed by
filtration-, and washed with hot water to remove the oxidation products.
This was followed by ether extraction.
An approximate yield of 0.5% of trans-caronic acid was
reported and cis-caronic acid was recovered in an unreported yield.
In
1967 Jarrett
used essentially the same method to recover
cis- and trans-caronic acids.
The following system was used;
•- d e l t a ~ 3 ~ c a r e n e .................. ■ . . .
*•
.
-
'
acetone
.
................
216.6 grams
.
................................ 3, 60.0
temperature range of reaction mixture.
ml.
l U .6 °C
water bath t e m p e r a t u r e ................
reaction time,
grams
''
•potassium permanganate
.
UlA
15-18
.
0C-
18 hours-
A yield of 6.5$ of cis-caronic acid and 0.5$ of trans-caronic
acid was reported.
1.
Equipment
The equipment used here for the oxidation reaction was,
as given in Figure 4, a 4,000 ml. Erlenmeyer flask which was placed in a
cold water hath and stirred with a one-quarter horsepower stirrer.
2.
The Batio of Raw Materials
In the same manner as in previous work, the potassium
permanganate oxidation of delta-3-carene was used again.
improved to
give- a yield of $.0% of cis-caronic acid.
This was
The relationship
between the conversion and the amount of oxidation agent was given in
Figure 5.
The following system was used: .
delta- 3- c a r e n e .........................
potassium permanganate
acetone
................
...............................
water bath t e m p e r a t u r e .................
'
260.0 grams
2,000 ml.
12 ..
5 0C
5 hours
reaction t i m e .................. ..
The separation procedure was that of Jarrett
4 l .4 grams
<
7
and 3*74 grams of cis-caronic
acid pure white crystals were obtained.
3.
Method
T h e c a r o n i c acid, for the purpose of esterification, was
-
prepared by potassium permanganate oxidation of delta- 3-carene with the
ratio of starting materials as mentioned a b o v e .
After the color of the
acetone solution appeared water white, i .e . , all the potassium permanganate
had b e e n consumed, stirring was stopped and separation of the oxidation
-7product.s absorbed on the manganese dioxide from the acetone was performed
by filtration.
methods.
The oxidation products were recovered from MnOg by two
The first method was stirring one part of solid manganese
dioxide with two parts of hot water and filtering.
This process was.
repeated until the filtrate had a pH value of 7.5 which was 9 . 3 - 1 0 .Ij- when
started.-
The second method was to make a slurry of one part manganese
dioxide with five parts of water and adding the theoretical amount of
sodium bisulfite to convert the manganese dioxide to m a n g a n o u s 'sulfate.
The caronic acid in either of the aqueous solutions was
in the form of potassium salt.
Reducing the pH value of the aqueous
solution to less than 1.0 to form caronic acid is a necessary step.
volume of. the solution was then reduced from 4,000 ml. to
The
250 ml. by
evaporating before being acidified.
The. mixture was extracted manually with 100 ml. of ethyl
ether four times.
The water layer after' extraction was concentrated to
saturation and extracted with ether again.
once more.
This process was repeated
The purpose of this treatment is to remove .most of the
inorganic by-products formed during the oxidation reaction and t h e .
acidification.
B.
The ether was recovered by distillation.
Esterification
Ho work had been done on the esterification of caronic acids;
13 14 15
a few articles reported the esterification of adipic acid.
Two essential, methods of the esterification of adipic acid ■ '
.
had been employed to ultimately produce the desired plasticizers.
—
8-
Iri one'of these methods, known as the high .temperature process
acid or acid 'anhydride was mixed 'with a substantial excess of-alcohol and .
heated- to- speed- up- the-reaction and to remove the -water, of, esterification.
A second method o f esterification involved the use of small excess of
alcohol but produced the esterification in the presence of a catalyst.
Typical catalysts which may be. employed are: hydrochloric acid, sulfuric
acid, aromatic sulfonic, acid such as benzene- sulfonic acid, toluene .
sulfonic acid, naphthalene sulfonic acid, etc.
’•
Other workers have reported, that inorganic- salts such as
'bisulfate salts, and sodium hydroxide in the presence of aluminum oxide
pellets
(5 mm. diameter), .were satisfactory catalysts.
All these methods turned out adipates in a good Quality and
quantity.
I.
Equipment;...
The equipment used-in this investigation consisted of a
vacuum distillation system,.given in Figure 6, proportional condensing
surfaces condenser^ and glass laboratory column.
--
Two different kinds .of columns were used in this ...
V . '
‘
■ .
■
•
experiment.
.
.
One yas'a one inch by.eighteen inch Vigreaux column and the
other- was a one inch by fifty-two-.inches glass'column with outsideheating coils.and a section f o r t y —two' inches.long.packed with 3/l6 inch,.-inside diameter' -single-turn rings of nuinbef.'26 B'&B- gage".stainless steel
wire.
-92.
Method
Several different straight-chain alcohols
(ethanol,
1-butanol, 1-hexanol), were used in the esterification of caronic acids
with hydrochloric acid, sulfuric acid, and p-toluene"' sulfonic acid as
catalyst.
As described in Section I I I - A , 250 ml. of alcohol and
200 ml.
of toluene- were added to the m i x t u r e .. The mixtures were then put
in a 1,000 ml. flask placed under a one inch b y eighteen Vigreaux column
to take off the w a t e r .
to
As soon as the temperature of the distillate rose
98 0C , the stopcock was closed and the column remained at total reflux
for five h o u r s .
The water formed had to be withdrawn continuously b y
azeotropic distillation with toluene during the esterification.
After five hours of total reflux, about 60 ml. of
unreacted alcohol were taken off by an entrainer.
The reflux ratio in
the distillation was twenty to one and was changed to thirty to one as
the boiling points chan g e d .
The entrainer, toluene, was recycled in the distillation.
The typical true-boiling-point curve was shown in Figure 7".
3.
Neutralization
The esterification was stopped as the overhead temperature
reached 104°C (boiling point of toluene at 630 m m .H g .), and all the
toluene added came out.
The stillpot was then taken off the column and
the bottoms mixture was neutralized with a few drops of 30% ammonium
hydroxide.
)
-10Neutralization should have particular attention because
either the acidity or causticity of the oil would cause reverse reaction
or hydrolysis of the esters.
Esters of these reactions would substantially
decrease the yield.
h.
Purification
The neutralized crude ester mixtures were washed with
100 ml. of hot water four times to take off inorganics and some other
impurities.
The oil was subjected to vacuum distillation under a
pressure of 20 mm.Hg.
A glass column with dimensions of one inch by
forty-two i n c h e s , stainless steel ring packed, was employed.
Water was
used as entrainer. to take off some low-boiling constituents.
The final
p r o d u c t , in the bottom, had a brown color.
C. ■ Gas Chromatography
Gas chromatography techniques were used both in analyzing the
various mixtures of esterification products and in preparing pure s a m p l e s '
for spectroscopy.
I.
Analysis of Esterification Products
The esters were analyzed with a Wilkens Aerograph
"Moduline" Model 202 dual column gas chromatograph having a dual thermal
conductivity detector.
SR r e c o r d e r .
The chromatograph was used with a Sargent Model
A 10-microliter syringe was used for injecting samples.
sample size was from two to eight microliters.
The
The chromatograph column -
was prepared here at Montana State University with the following
-11specifications :
•
stationary phase
'
. . . .............. 5$ carbowax 20M.
s u p p o r t ............. ..
chr.omosort T.
column . . . ..............
201 x l / V copper.
operating c o n ditions:
column temperature
.............
Hg carrier gas■■r a t e ...........
2.
2000C
60 c.c./min.
Analysis Techniques
a.
Comparison of Retention Times
..
The principle of gas chromatography analysis is that
a given compound has a constant retention time unless the chromatograph
condition changed.
T h e r e f o r e , if an unknown sample has a retention time
identical with that of a known.sample, it can be said that there is a
certain compound in the unknown sample that possibly has the same identity
as that of the known compound with the same retention time.
.Ho w e v e r ,
there is also.the o t h e r .possibility that none of the other compounds in'
the unknown has the identity of the known compound with that retention
time.
b.
Peak Enhancement
-For further comparison, an unknown compound may be
mixed with a known compound.
Such a mixture will produce one of two
r e a ctions; (l) ' one peak which will be larger.in size'or (2) an extra
peak.
The initial case is the so-called "peak enhancement" which almost
always p r o v e s .the identity of the compound of primary concern.
-12- •
c.
Preparative Gas Chromatography
Preparative chromatography is one of the. best "ways to
collect small amounts of pure compounds for analysis by infrared or
nuclear magnetic resonance spectroscopy.
Each composition is separated
in the chromatograph column and individual compounds are collected at the
chromatograph e x i t .
d.
Equipment
■ The Wilkins Model 202 gas chromatograph with thermal
conductivity detec t o r , 5% carbowax 20 M chromatograph c o l u m n , and a
100-microliter syringe were used. .
e.
Sample Collection
The sample size injected was 30-60 microliters.
The
pure compounds were collected at the chromatograph exit in pieces of b mm.
glass tubing (Figure
acetone bath.
8 ).
The loop of the tubing was immersed in a dry ice-
Vapor was observed coming out of the glass t u b e .
This
atomizing effect was partially minimized by bubbling the vapor into'- the
ether. ■
'
.D. -.p H 'Measurement-
■ ■
. A Beckman Model H2 pH.meter with a Sargent S-30072-15
combination electrode was used for pH measurements.
The meter was
standardized with a buffer solution having a pH value close to that of
the unknown solution.
7.0, and 3.0.
Commonly used buffer solutions had pH's of 9*0,
The reproducibility of pH measurements was found to be about.
- 0.1 pH u n i t s .
-13E.
Spectroscopy
The infrared spectra were run on a Beckman IR5A
spectrophotometer in the Chemistry Department of Montana State University.
Ho solvent was used in this investigation.
Typical operating conditions
for the Beckman IR5A unit were as follows:
sample ...............................
Esters
p a t h ............................... 0.0$ mm.
(ltfaCl P l a t e s )
r e f e r e n c e ............. -............ Air
ordinate scale
.............
g a i n .................................
F.
Double Beam
6.0
Manual Integration Techniques for Calculation of Yield
Through Chromatographic Peaks
Conversion percentage of the esterification was determined by
estimating through the peak area of the gas chromatogram.
The principal manual methods for quantitative evaluation of
gas chromatographic peaks a r e : (l) determination of peak area from height
and width measur e m e n t s , (2 ) by triangulation, (3) by planimetry, (U) by
cutting out the peak and weighing the paper, or (5) by measurements of
only the peak height.
A l l of these measurements and operations are
carried out on peaks as recorded on the chromatogram.
little to recommend it.
Triangulation has
Cutting and weighing is vulnerable because of
variations in paper thickness.
Planimetry is less precise than height-
width integration for peaks of small area but is comparable or somewhat
better in precision for large.areas
i
Cutting and weighing method was u s e d in this experiment.
Peaks including "base lines were printed on heavy paper and cut with, small'
scissors.
The paper was weighed -on a Mettler analytic "balance with 0.1 m g
sensitivity.
:
.
I
IV.
DISCUSSION OF RESULTS
A.
.
Identification of Products
■Di-Butyl Caronate
The production of di-hutyl caronate from the oxidation of
delta-3-carene in 27.3% yield was discussed in Section I I I - B .
The samples collected from the chromatograph exit were
compared with di-butyl esters which were made with pure cis-caronic.a c i d ;
the methods were illustrated in Sections I I I - C , and I I I - E .
peak in Figure 9 is identical with the peak in Figure 10.
they gave-the same infrared spectra,
The eighth
Furthermore,
(Figures 11, 12).
T h e 'ester was not determined to be whether di-butyl cis-caronate or di-butyl trans-caronate due to the fact that the heat treatment, may
cause the rotation of the bonds.
Di-Butyl Homocaronate
,
In Figure 9, the component producing, the peak next t o the peak
of di-butyl caronate was in^ a yield of 1'8.2%.
di-butyl h o mocaronate.
This compound is probably
This assumption is made on the previous work of
■ 7
the methyl ester -of homocaronic acid by Jarrett who noted t h a t :
Tl:. ’ Some, homocaronic. acid, was found in his. potassium
permanganate oxidation of delta- 3-carene,
. 2.
In the gas chromatograms, methyl homocaronate is next to
methyl caronate, and,
3.
.
'
■
Infrared- spectra of methyl caronate and methyl homocaronat
of which we obtained similar spectra.
I
-16- ■
There is no available outside source for assuring this this
assumption is correct.
B u t , by comparing the infrared spectra (Figures
11 and 13), and the gas chromatogram (Figure
9)5 it has the most possibil­
ity that this compound is di-butyl homocaronate.
B. ' Calculation of Conversion Percentage
The conversions of caronic acid esters were determined and
calculated by the method illustrated in Section III-F.
Errors in
quantitative evaluation of peaks on a chart are additional to errors
occuring earlier in the chromatographic process.
Errors associated with
peak measurements are primarily indeterminate errors.
Indetermined as
well as determined errors were introduced in the operations of sample
injection and r e c ording.
The 1.25% deviation in cutting and weighing method were
caused b y nonhomogeneous p a p e r , pickup of moisture, grease from handling,
and these errors were minimized by taking an average of several
experimental d e t e r m inations.•
.
V.
CONCLUSIONS
The purpose of this research work was',to- optimize the', oxidation
reaction of delta-3-carene with potassium permanganate as an oxidizing
agent.
Results of this investigation are summarized below:
1.
27.3% of caronic acid and 18.2% of homocaronic acid, in the
form of di-butyl e s t e r s , were recovered from the potassium permanganate
oxidation of delta- 3-carene in acetone; the yield reported in former
work for cis-caronic acid and trans-caronic acid were
6 .5% and 0 .5%,
respectively.
2.
The esters have a color of light-brown.
were white or yellow.
Previous colors
The color is introduced by heat-treatment for a
relatively' long reaction time.
3.
The final product of esterification of the oxidation product
is a mixture consisting of two essential compounds, i.e.,, di-butyl
caronate and di-butyl homoca r o n ate.
k.
The reaction time and reaction temperature increased as the
molecular weight of the alcohol used increased.
5-
The higher the molecular weight of the ester, the more
difficult the separation.
V I .. RECOMMENDATIONS
Di-Tmtyl caronate and di-butyl homocaronate have been identified
as components of the esterification product from the potassium permanganate
oxidation of delta-3-carene in acetone.
A process of producing 27.3$ of
di-butyl caronate and. 18.2$ of di-butyl homocaronate has been developed.
The incompleteness o f this process is that the esters remain in the form
of a m i x t u r e .
The reasons causing this drawback of the esterification of
caronic acid are undete r m i n e d .
Recommendations for further work on the research of delta-3-carene
are listed below:
1.
Investigate the use of an oxidizing agent other than
potassium permanganate leading the reaction toward the desired mechanism.
2.
Convert caronic acid into chloride before carrying out the
esterification.
•
.
.
"
3.
Make higher esters of caronic acid by transesterification.
U.-
Develop a pilot scale process for the production of caronic
acid esters.
•
.
'•
V
•>
;;
'
/
=
'APPENDIX
.D-
-20-
Figure I.
The Structure of Delta-3-Carene
-21-
HOOC
COOH
Cis-Caronic Acid
Trans-Caronic Acid
HOOC
COOH
HOOC
Cis-Homocaronic Acid
COOH
Trans-Hoiaocaronic Acid
Figure 2.
Cyclopropane Eing-Containing Dicarboxylic Acids
Derived from Delta— 3-Carene .
-22-
HgC^OOC
di-Butyl-Caronate
HgC^OOC
V
COOC^Hg
COOC^Hg
di-ButyI-Homocaronate
HOOC
mono-Butyl-Caronate
HOOC
.COOC^Hg
mono-Butyl-Homoc aronat e
Figrue 3.
Esters Derived from Cyclopropane Ring-Containing
Dicarboxylic Acids.
-23-
Stirrer
Cooling Water
Reaction Flask
Standpipe
To Drain
Figure 4.
Apparatus for Potassium Permanganate Oxidation
of Delta-3-Carene in Acetone
Cis-Caronic Acid, Conversion
Weight of Oxidizing Agent (unit: 216.6 grams of K M n O v )
Figure
Conversion % vs. Amount of Oxidizing Agent
-25-
Cooling water
cn
ZjS
p •+• Cooling water
Thermometer
A = * - ,
(ly=®=^
v
Stainless
Steel r i n g s ,
3/16" ID --
p
r
J
©
Vacuum
Trip
-Receiver
|-(pc)
i- - -
y
Dry iceAcetone bath
U
Xu -
Thermometer
Heating mantle
Figure
6 . Vacuum Distillation System.
To vacuum
Scale Changed
Pressure: 630 ram.Hg.
I-BuOH - Tolu.
(Toluene
Pressure: 20 mm.Hg.
Scale Changed
1200
Distillate, grams
Figure 7.
True-Boiling-Point Curve of I-Butanol-Caronic Acids-Toluene System.
-27-
Chromatograph Exit
Rubber
Septum
Wilkens
Aerograph
Model 202
"Moduline"
Gas
Chromatograph
Glass Sample Tube
- Ether
— Dewar Flask
--
Figure 8.
Dry Ice-Acetone
Sample Collection in Preparative Gas Chromatography.
Time (unit: 12 mi n u t e s )
Figure 9•
Gas Chromatogram of the Esterification Product
Time (unit: 12 m inutes)
Figure 10.
Gas Chromatogram of Di-Butyl Caronate.
WAVfNUMMt CM'
Im
Trpri
CONCENftATiON__________
I
UJ
0
1
SAECrtOtMOTOMfTEt
Figure 11
Infrared Spectrum of the D i -Butyl Caronate from the Mixture of
Esterification Pr o d u c t .
WAVtwu-M
Cm
TrTTnrrTfm-TfnfrpTir
i -- : - r
COwCtNllAtKM__________
I
LO
H
I
SFECTIOfMOTdMEtH
Figure 12.
Infrared Spectrum of the Di-Butyl Caronate
w a v e n j m IM
T T T T J l IrI p T T T j n i T ] TTl I
Figure 13.
Cm
rrfilli|InijTinjm rnt •ifTiT
Infrared Spectrum of Di-Butyl Homocaronate
Pressure
Figure l4.
Cox Chart for Various Azeotropes.
LITERATURE CITED
1.
A c h a r y a , S. P., Tetrahedron L e tters,' 3j4_, 4117-22 (1966).
2.
M c C a n d l e s s , F. P., Chemical E ngineering.Department, Montana State
University, personal communication, (1967)•
3.
B e r g , L.-, Chemical Engineering Department, Montana State University,
personal communication, (1968).
4.
Simonsen, J. L., R a u , M. G., J o u r . Cherny Soc., 1 2 3 , 549'3 (1923).
5.
S e m m l e r , F. ¥., von Schiller, H., Berichte Deutschen C h e m . Gesell., 6 0 ,
1591,
6.
(1927).
’
Gibson, C. S., S i m o n s e n , J Y L . ,
Jour. C h e m . S o c . , 1 3 2 , 3054 (1929).
7 . J a r r e t t , J. H'. , "The Production of Cis- and Trans-Caronic Acids from ■
Delta-3-Carene", Department of Chemical Engineering, Montana State
University, (1968).
8.
Reid, H". G., U. S. Pat. 2517351,
(Aug. I, 1950).
9«
Morris, R. E., Hollister, J. W., Rubber A g e , 20, 195-203, ■(1951) •
10. Kyrides;, U. S. Pa. 2073938,. (Mar. 1 6 , 1 9 3 7 ) .
11.. Muir, W. M., Encyclopedia of Chemical Technology, "Acids, Dicarboxylic",
240-754, (1963 Edition)..
12. Simorisen, J. L., Jour. C h e m . S o c . , 1 1 7 , 570, (1920.) .
13. Schetelich, A.-A., Betts, J. L . ,’ U. S. Pat. 28834l6,
(Apr. 21, 1959):
14. Heuter ,-R., Hen t s c h e l , K., C h e m . Abs -. V o l . 54., (i960).
15. H a K a n i s h i , S., C h e m . A b s . V o l .
58, (1963).
16. Ball, D. L., H a r r i s , W. E., J o u r . Gas C h roma. , V o l . 5., (1967).
17. "Handbook of Chemistry and Physics", 48th Ed. , Chemical Rubber
Publishing Company (1967- 68).
•l8. Berg, L., "Aseotrcpic Distillation", Department of Chemical Engineering,
Montana State University, (1948)..
19. Bellamy, L. J . , . "The Infrared Spectra of Complex M o lecules", Wiley and •
Sons, Incorporated, H e w Y o r k , (1958)•
3
N378
0379
cop.2
Gharng, Tom Ting
Preliminary investi­
gation of caronic acid
esters
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