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Analysis and identification of some aminoether alcohols and their ethers
Journal of Chromatography,
410 (1987) 447-452 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands CHROM. 19 985
Note
Analysis ethers
and
identification
HENRYK SZEWCZYK and EUZEBIUSZ
of some
aminoether
alcohols
and
their
DZIWENSKI
Institute of Heavy Organic Synthesis, Kqdzierzyn-Koile
(Poland)
and JAN SZYMANOWSKI* Technical University of Poznar’i, PI. Skiodowskiej-Carrie 2, 60-955 Poznah (Potand)
(Received August 6th, 1987)
In previous studieslp3 gas chromatography and mass spectrometry were used to determine the composition of N,N’-di(polyoxyethylene)alkylamines and of N-oligooxyethylene mono- and dialkylamines. Arithmetic retention indices were determined for homologues with various length of oxyethylene chains and alkyl groups, and they were used to identify these compounds. The mass spectra were also registered and discussed. This paper deals with aminoether alcohols and their ethers of the following formulae:
(CHDW)nR
W-LCH2O)nR
/
/ and
HOCHzCH2N
R(OCH2CH&N
\
\ (CHKH2GLR
(CH&H2G),R
where R = C4H9, C6H1s or CsH17, n = 1,2 and 3, and m = 2 and 3. The synthesis of these compounds and their polarities, as determined by reversed-phase gas chromatography, were discussed previously4. Their interfacial activity at the water-toluene interface was also determined and discussed5. The aims of this work were to determine the arithmetic retention indices and mass spectra of the investigated compounds and to discuss and correlate these parameters with the structures of the compounds. EXPERIMENTAL
A gas-liquid chromatograph (Perkin-Elmer Model 900) with a flame ionization detector was used. The separation was carried out in stainless-steel columns (0.9 m x 2.7 mm I.D.). Chromosorb G AW DMCS (60-100 mesh) was used as the support and silicone resin OV-17 (phenylmethylsiloxane) (3%) as the liquid phase. Argon OOZI-9673/87/$03.50
0
1987 Elsevier Science Publishers B.V.
NOTES
448
was used as the carrier gas, and its flow-rate was 15 cm3/min. The temperatures of the injector and the detector were 320°C. The column temperature was raised from 150 to 320°C at 4”C/min. Trimethylsilyl derivatives were prepared in a glass micro reaction vessel (capacity 3 cm3) fitted with a PTFE-faced rubber septum and cap (Supelco, Bellefonte, PA, U.S.A.). A sample of cu. 0.05 g of the aminoether alcohol was weighed and 0.5 cm3 of N,O-bis (trimethylsilyl)-acetamide (POCh, Gliwice, Poland) was added. The sealed reaction vessel was maintained at 70°C for 40 min and shaken from time to time. After this time silylation was complete and the product was analysed. A mass spectrometer (LKB, type 2091, Bromma, Sweden) was used. The samples were introduced by the direct inlet. An ionization energy of 70 eV, an ion-source temperature of 250°C a voltage of ion acceleration of 3.5 kV and a sweep time of 7 s were employed. The products were analysed directly or in the form of their trimethylsilyl derivatives. RESULTS AND DISCUSSION
Analytical data for investigated aminoether alcohols and their ethers are given in Table I. Aminoether alcohols (compounds 1-5) were analysed in the form of their trimethylsilyl derivatives. Only small peaks of impurities were observed on the chromatograms. Their contents, as estimated from the surface area of the peaks and assuming correction coefficients equal to 1, are in the range 0.05535%. Sample chromatograms for mixtures of compounds l-5 and 6-9 are given in Figs. 1 and 2, respectively. The values of experimentally determined arithmetic retention indices are given in Table I. They demonstrate that an oxyethylene group and a methylene group correspond to cu. 300 and 100 units, respectively, on the arithmetic retention scale. Thus, it seems that increments of the arithmetic retention index determined pre-
TABLE I ANALYTICAL
DATA FOR AMINOETHER
Compound No.
Formula
ALCOHOLS AND THEIR ETHERS
OLCH20),R / HOCHZCH~N \ (CHZCH20),R
n
m
R
Impurities content(%)
Cd-b
1.7 2.7
1900
1949
GH9
2511
2547
CsHlz CsHiz
0.6 0.6
2874 3235
2947 3347
C~HP
3.0
3103
3145
GH9
2400 3263 3824
2422 3293 3893
4385
4493
1
-
2 2 2 3
-
1 2
2 3
2
3
‘S&IS
0.05 0.8 1.6
2
3
CSH17
3.5
IA
4”
(CHDLO),R / R(OCH#H&N \
(CH&HzO),R
C4H9
NOTES
449
/ 7,
&*I
Fig. 1. Chromatogram
[A]
Fig. 2. Chromatogram
J
6-l
4
rb --
---
-.-
---~
of a mixture of compounds
30
,___~_
_
---
10
l-5.
PO
of a mixture of compounds 6-9.
40 1'
0
450
NOTES
viously for characteristic fragments present in different oxyethylated alkylamines3 can also be used for the group of compounds under consideration. Thus, dlA(CH2) = dZA(CH3) = 100, Al*(N) = 26, MA(O) = 99, &(OSi(CH&) = 325 and dZA(OCH2CHz) = 299, and the arithmetic retention index can be estimated as k IA = C ni - dIA,iy where ni denotes the number of a characteristic group i present i=l
in the compound considered, dJA,i stands for the increment of 1~ for the group i, and k is the number of the characteristic groups. The values calculated in this way are given in Table I as Pi”. Good agreement between experimental and calculated values is observed. The average relative error is cu. 1.9%. The following linear relations are observed: IR = 1000 + 300.75 n!” for compounds I,2 and 5; IR = 1787 + 90.5 ny for compounds 2, 3 and 4; I, = 2141 + 93.5 nz for compounds 7, 8 and 9; where n:” and n:’ denote the total number of oxyethylene groups and carbon atoms in oligooxyethylene chains and alkyl groups, respectively. The increments calculated as the gradients of above relations are then equal to dlA(CH2CH20) = 301, dIA(CH2) = 92 and dIA(0) = 117. Thus, these values differ only somewhat from the previous ones. This means that the increments depend on the structures of the compounds considered, but this effect is relatively weak for the groups of compounds studied. The arithmetic retention indices of the compounds under consideration can also be estimated from their connectivity indices 6. Linear relations were obtained for compounds l-5 and 6-9, respectively (Fig. 3). Their gradients are almost the same and equal to 189.2 and 188.7, respectively. Thus, 1 unit of the connectivity index equal to 189 can be used to estimate the unknown values of the arithmetic retention index for other homologues of the series.
3500 -
10
Fig. 3. Relation
Q
I 94
between
16
j 18 PO connactrvity
the arithmetic
retention
I 22
)
index
index and the connectivity
index.
451
NOTES
MW333
Fig. 4. Mass spectrum of compound
I,.
For all the compounds investigated the mass spectra were taken, and two sample spectra, together with fragmentations, are presented in Figs. 4 and 5. In all these spectra parent ions of low intensity are present at m/z 333, 421, 477, 533 and 509 for trimethylsilyl derivatives of compounds l-5, respectively, and at m/z 361, 493, 577 and 661 for compounds 6-9, respectively. The main fragment ions are
Fig. 5. Mass spectrum of compound 8.
NOTES
452
formed as a result of fission of the C-C bond in the oxyethylene units linked to the nitrogen atom. In each case the intensities of these main ions are in the ratio of cu. 100:50, e.g. at m/z 246 and 418 and 374 in Figs. 4 and 5, respectively. This is a result of a similar tendency for splitting of the C-C bond in each oxyethylene unit linked to the nitrogen atom and the presence of two equal alkyl chains. Partial splitting of the C-O bond also occurs in these oxyethylene groups, and appropriate ions of low intensities are observed, e.g. at m/z 260 and at m/z 388 and 432 in Figs. 4 and 5, respectively. Similar partial splitting of the C-C and C-O bonds in the next oxyethylene groups also occurs, and appropriate ions of very low intensities are observed. The next characteristic ions are formed by splitting of alkyl radicals from terminal hydrocarbon chains. Tons at m/z 73, [Si(CH&]+, are also observed. The mass spectra obtained fully confirm the structure and purity of the investigated compounds. CONCLUSIONS
The increments determined for characteristic fragments of aminoether alcohols and their ethers can be used to estimate the values of the arithmetic retention index within an error of less than 2%. The values of these increments depend on the structures of the compounds considered, but this effect is relatively small. The arithmetic retention indices of the compounds considered can also be estimated from their connectivity indices, assuming that 1 unit of the connectivity index is equivalent to 189 units of the arithmetic retention index under the chromatographic conditions used. The mass spectra fully confirm the structure and purity of the investigated compounds. The main fragment ions are formed by Gission of the C-C bond in the oxyethylene units linked to the nitrogen atom. ACKNOWLEDGEMENTS
We thank Prof. J. Beger and Dr. K. Ebert for the synthesis of aminoether alcohols and their etheis. REFERENCES 1 2 3 4 5 6
J. Szymanowski, H. Szewczyk and W. Jerzykiewicz, Tenside D&erg., 18 (1981) 130. H. Szewczyk, J. Szymanowski and W. Jerzykiewicz, Ten&& Deterg., 19 (1982) 287. J. Szymanowski, A. Voelkel and H. Szewczyk, J. Chromatogr., 360 (1986) 43. A. Voelkel, J. Szymanowski, J. Beger and K. Ebert, J. Chromatogr., 391 (1987) 373. J. Szymanowski and K. Prochaska, J. Colloid Interface Sci., submitted for publication. M. Randic, J. Chromatogr., 161 (1978) 1.
410 (1987) 447-452 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands CHROM. 19 985
Note
Analysis ethers
and
identification
HENRYK SZEWCZYK and EUZEBIUSZ
of some
aminoether
alcohols
and
their
DZIWENSKI
Institute of Heavy Organic Synthesis, Kqdzierzyn-Koile
(Poland)
and JAN SZYMANOWSKI* Technical University of Poznar’i, PI. Skiodowskiej-Carrie 2, 60-955 Poznah (Potand)
(Received August 6th, 1987)
In previous studieslp3 gas chromatography and mass spectrometry were used to determine the composition of N,N’-di(polyoxyethylene)alkylamines and of N-oligooxyethylene mono- and dialkylamines. Arithmetic retention indices were determined for homologues with various length of oxyethylene chains and alkyl groups, and they were used to identify these compounds. The mass spectra were also registered and discussed. This paper deals with aminoether alcohols and their ethers of the following formulae:
(CHDW)nR
W-LCH2O)nR
/
/ and
HOCHzCH2N
R(OCH2CH&N
\
\ (CHKH2GLR
(CH&H2G),R
where R = C4H9, C6H1s or CsH17, n = 1,2 and 3, and m = 2 and 3. The synthesis of these compounds and their polarities, as determined by reversed-phase gas chromatography, were discussed previously4. Their interfacial activity at the water-toluene interface was also determined and discussed5. The aims of this work were to determine the arithmetic retention indices and mass spectra of the investigated compounds and to discuss and correlate these parameters with the structures of the compounds. EXPERIMENTAL
A gas-liquid chromatograph (Perkin-Elmer Model 900) with a flame ionization detector was used. The separation was carried out in stainless-steel columns (0.9 m x 2.7 mm I.D.). Chromosorb G AW DMCS (60-100 mesh) was used as the support and silicone resin OV-17 (phenylmethylsiloxane) (3%) as the liquid phase. Argon OOZI-9673/87/$03.50
0
1987 Elsevier Science Publishers B.V.
NOTES
448
was used as the carrier gas, and its flow-rate was 15 cm3/min. The temperatures of the injector and the detector were 320°C. The column temperature was raised from 150 to 320°C at 4”C/min. Trimethylsilyl derivatives were prepared in a glass micro reaction vessel (capacity 3 cm3) fitted with a PTFE-faced rubber septum and cap (Supelco, Bellefonte, PA, U.S.A.). A sample of cu. 0.05 g of the aminoether alcohol was weighed and 0.5 cm3 of N,O-bis (trimethylsilyl)-acetamide (POCh, Gliwice, Poland) was added. The sealed reaction vessel was maintained at 70°C for 40 min and shaken from time to time. After this time silylation was complete and the product was analysed. A mass spectrometer (LKB, type 2091, Bromma, Sweden) was used. The samples were introduced by the direct inlet. An ionization energy of 70 eV, an ion-source temperature of 250°C a voltage of ion acceleration of 3.5 kV and a sweep time of 7 s were employed. The products were analysed directly or in the form of their trimethylsilyl derivatives. RESULTS AND DISCUSSION
Analytical data for investigated aminoether alcohols and their ethers are given in Table I. Aminoether alcohols (compounds 1-5) were analysed in the form of their trimethylsilyl derivatives. Only small peaks of impurities were observed on the chromatograms. Their contents, as estimated from the surface area of the peaks and assuming correction coefficients equal to 1, are in the range 0.05535%. Sample chromatograms for mixtures of compounds l-5 and 6-9 are given in Figs. 1 and 2, respectively. The values of experimentally determined arithmetic retention indices are given in Table I. They demonstrate that an oxyethylene group and a methylene group correspond to cu. 300 and 100 units, respectively, on the arithmetic retention scale. Thus, it seems that increments of the arithmetic retention index determined pre-
TABLE I ANALYTICAL
DATA FOR AMINOETHER
Compound No.
Formula
ALCOHOLS AND THEIR ETHERS
OLCH20),R / HOCHZCH~N \ (CHZCH20),R
n
m
R
Impurities content(%)
Cd-b
1.7 2.7
1900
1949
GH9
2511
2547
CsHlz CsHiz
0.6 0.6
2874 3235
2947 3347
C~HP
3.0
3103
3145
GH9
2400 3263 3824
2422 3293 3893
4385
4493
1
-
2 2 2 3
-
1 2
2 3
2
3
‘S&IS
0.05 0.8 1.6
2
3
CSH17
3.5
IA
4”
(CHDLO),R / R(OCH#H&N \
(CH&HzO),R
C4H9
NOTES
449
/ 7,
&*I
Fig. 1. Chromatogram
[A]
Fig. 2. Chromatogram
J
6-l
4
rb --
---
-.-
---~
of a mixture of compounds
30
,___~_
_
---
10
l-5.
PO
of a mixture of compounds 6-9.
40 1'
0
450
NOTES
viously for characteristic fragments present in different oxyethylated alkylamines3 can also be used for the group of compounds under consideration. Thus, dlA(CH2) = dZA(CH3) = 100, Al*(N) = 26, MA(O) = 99, &(OSi(CH&) = 325 and dZA(OCH2CHz) = 299, and the arithmetic retention index can be estimated as k IA = C ni - dIA,iy where ni denotes the number of a characteristic group i present i=l
in the compound considered, dJA,i stands for the increment of 1~ for the group i, and k is the number of the characteristic groups. The values calculated in this way are given in Table I as Pi”. Good agreement between experimental and calculated values is observed. The average relative error is cu. 1.9%. The following linear relations are observed: IR = 1000 + 300.75 n!” for compounds I,2 and 5; IR = 1787 + 90.5 ny for compounds 2, 3 and 4; I, = 2141 + 93.5 nz for compounds 7, 8 and 9; where n:” and n:’ denote the total number of oxyethylene groups and carbon atoms in oligooxyethylene chains and alkyl groups, respectively. The increments calculated as the gradients of above relations are then equal to dlA(CH2CH20) = 301, dIA(CH2) = 92 and dIA(0) = 117. Thus, these values differ only somewhat from the previous ones. This means that the increments depend on the structures of the compounds considered, but this effect is relatively weak for the groups of compounds studied. The arithmetic retention indices of the compounds under consideration can also be estimated from their connectivity indices 6. Linear relations were obtained for compounds l-5 and 6-9, respectively (Fig. 3). Their gradients are almost the same and equal to 189.2 and 188.7, respectively. Thus, 1 unit of the connectivity index equal to 189 can be used to estimate the unknown values of the arithmetic retention index for other homologues of the series.
3500 -
10
Fig. 3. Relation
Q
I 94
between
16
j 18 PO connactrvity
the arithmetic
retention
I 22
)
index
index and the connectivity
index.
451
NOTES
MW333
Fig. 4. Mass spectrum of compound
I,.
For all the compounds investigated the mass spectra were taken, and two sample spectra, together with fragmentations, are presented in Figs. 4 and 5. In all these spectra parent ions of low intensity are present at m/z 333, 421, 477, 533 and 509 for trimethylsilyl derivatives of compounds l-5, respectively, and at m/z 361, 493, 577 and 661 for compounds 6-9, respectively. The main fragment ions are
Fig. 5. Mass spectrum of compound 8.
NOTES
452
formed as a result of fission of the C-C bond in the oxyethylene units linked to the nitrogen atom. In each case the intensities of these main ions are in the ratio of cu. 100:50, e.g. at m/z 246 and 418 and 374 in Figs. 4 and 5, respectively. This is a result of a similar tendency for splitting of the C-C bond in each oxyethylene unit linked to the nitrogen atom and the presence of two equal alkyl chains. Partial splitting of the C-O bond also occurs in these oxyethylene groups, and appropriate ions of low intensities are observed, e.g. at m/z 260 and at m/z 388 and 432 in Figs. 4 and 5, respectively. Similar partial splitting of the C-C and C-O bonds in the next oxyethylene groups also occurs, and appropriate ions of very low intensities are observed. The next characteristic ions are formed by splitting of alkyl radicals from terminal hydrocarbon chains. Tons at m/z 73, [Si(CH&]+, are also observed. The mass spectra obtained fully confirm the structure and purity of the investigated compounds. CONCLUSIONS
The increments determined for characteristic fragments of aminoether alcohols and their ethers can be used to estimate the values of the arithmetic retention index within an error of less than 2%. The values of these increments depend on the structures of the compounds considered, but this effect is relatively small. The arithmetic retention indices of the compounds considered can also be estimated from their connectivity indices, assuming that 1 unit of the connectivity index is equivalent to 189 units of the arithmetic retention index under the chromatographic conditions used. The mass spectra fully confirm the structure and purity of the investigated compounds. The main fragment ions are formed by Gission of the C-C bond in the oxyethylene units linked to the nitrogen atom. ACKNOWLEDGEMENTS
We thank Prof. J. Beger and Dr. K. Ebert for the synthesis of aminoether alcohols and their etheis. REFERENCES 1 2 3 4 5 6
J. Szymanowski, H. Szewczyk and W. Jerzykiewicz, Tenside D&erg., 18 (1981) 130. H. Szewczyk, J. Szymanowski and W. Jerzykiewicz, Ten&& Deterg., 19 (1982) 287. J. Szymanowski, A. Voelkel and H. Szewczyk, J. Chromatogr., 360 (1986) 43. A. Voelkel, J. Szymanowski, J. Beger and K. Ebert, J. Chromatogr., 391 (1987) 373. J. Szymanowski and K. Prochaska, J. Colloid Interface Sci., submitted for publication. M. Randic, J. Chromatogr., 161 (1978) 1.