Environ. Sci. Technol. 1993, 27, 1319-1326
Polychlorinated Diphenyl Sulfides: Preparation of Model Compounds, Chromatography, Mass Spectrometry, NMR, and Environmental Analysis Selja Slnkkonen,’ Erkkl Kolehmalnen, Katrl Lalhla, Jaana Koistlnen, and Tllna Rantlo
Department of Chemistry, University of
Jyvaskyll, P.O.
Box 35, Jyvaskyla 40 351, Finland
Some polychlorinated diphenyl sulfides were prepared by chlorination of diphenyl sulfide with sulfuryl chloride and by Friedel-Crafts-type reaction from 1,2-dichlorobenzene and sulfur. Individual isomers from the reaction mixtures were isolated by reversed-phase high-performance liquid chromatography. Mass spectra show the degree of chlorination of different compounds, and ‘H and I3C NMR spectra verify their structures. Three trichloro isomers were shown to be 2,2’,4-, 2,4,4’-, and 2,4’,6-trichlorodiphenyl sulfides and two symmetric tetrachloro isomers bis(2,4dichlorophenyl)and bis(3,4dichlorophenyl) sulfides. Chlorine-induced 13CNMR substituent chemical shifts (SCS) have been calculated and compared with the experimental ones in the case of bis(2,4-dichlorophenyl) sulfide. Four stack gases from a waste incinerator and six pulp mill effluents from two bleaching plants were screened for the polychlorinated diphenyl sulfides. Trichlorodiphenyl sulfides were found from five pulp mill effluent samples and tri- and tetrachlorodiphenyl sulfides from two stack gas samples. Introduction
Polycyclic aromatic sulfur heterocycles (PASH) and polycyclic aromatic hydrocarbons (PAH) are commonly found in the environment (1-5). Crude oil and its refinery products have been found to be the main source of many different PASHs present within various environmental compartments. Their presence is mainly due to oil pollution, caused by oil spillages and the combustion of crude oil and other oil products, with a reduced number being of natural origin. Many PASHs are formed in different industrial processes and in the combustion of waste products. Some oxidized and chlorinated PASHs which possess biological activity and phytotoxity are manufactured to be used as pesticides (61, e.g., dibenzothiophene sulfoxide and 2,4,4’,5-tetrachlorodiphenyl sulfide. As our interest has been the polychlorinated and polymethylated dibenzothiophenes (PCDBTs and PMeb DBTs) (7-101,some model compounds have been prepared for environmental and toxicological analysis. Recently, a number of PCDBTs have been found in bleached pulp mill effluents (II),and they are also formed during waste combustion (10, 12,131. Preliminary investigations have shown that the PCDBTs have many toxicological effects of the same type as the TCDDs and PCBs (14). The nonpolar aromatic compound fractions obtained from many environmental samples have remained very complex and still contain many unknown chlorinated compounds after extraction and several chromatographic purifications. These unknown chlorinated compounds interfere in the GC/MS analysis of the chlorinated PASHs evenat high resolutions (10 000-20 000) (15),and some of them are potentially highly toxic (16). Polychlorinated diphenyl sulfides (PCDPS) are environmentally interesting compounds due to their structural 00 13-936X/93/0927- 1319$04.00/0
0 1993 American Chemical Society
resemblance with polychlorinated diphenyl ethers (PCDE) (17). The lH and 13C NMR spectroscopic properties of DPS and para-substituted DPSs are reported in the literature (18-21). NMR spectroscopic methods are necessary in isomer-specific structure elucidation of sub17), because mass spectroscopy stituted aromatics (8,9, alone is not capable of that. In this study, PCDPS model compounds were prepared by direct chlorination of DPS with sulfuryl chloride and by Friedel-Crafts- type reaction from 1,2-dichlorobenzene and sulfur. The syntheses mixtures were fractionated by reversed-phase HPLC, and the structures of pure compounds were determined by GUMS and lH NMR spectroscopy. Four stack gas samples from a waste incinerator and six pulp mill effluent samples from two different bleaching plants were screened for the occurrence of PCDPSs by selected-ion monitoring HRGC/HRMS. Experimental Section
Preparation of Model Compounds. The PCDPSs were synthesized by two different methods. Synthesis 1 . Chlorination of DPS with sulfuryl chloride: 2,4’,6- (HPLC fr. l / l ) , 2,2’,4- (HPLC fr. 2/1), and 2,4,4’-TriCDPS (HPLC fr. 3/1)and bis(2,4-dichlorophenyl) sulfide (HPLC fr. 4/1). Approximately 100 mg of DPS was dissolved in a mixture of 0-and p-chlorotoluene (50: 50) (22). Dropwise addition of sulfuryl chloride was finished when the main products were tri- and tetraCDPSs (GC/MS). During the addition of sulfuryl chloride (about 2 h), the temperature was kept at 70-80 OC. Synthesis 2. Preparation of tetraCDPSs from 1,2dichlorobenzene and sulfur: bis(3,4-dichlorophenyl) sulfide (HPLC fr. 5/21. A total of 500 mg of 1,a-dichlorobenzene and 200 mg of sulfur were mixed and heated on a water bath to 60-70 OC. Then dry was added to the continuously stirred reaction mixture, which was kept a t 60-70 OC for 4 h. HPLC Fractionation. The two syntheses mixtures of PCDPSs were fractionated by HPLC with analytical reversed-phase columns collecting the fractions obtained from repeated identical HPLC separations (10-20). Three kinds of RP columns, Silasorb C 8 SPH (ELSICO),Silasorb C 18SPH (ELSICO),and Spherisorb S5 ODs-2, were used. The HPLC system contained a Merck-Hitachi, L6200 Intelligent pump; a Shimadzu SPD GAV UV-VIS spectrophotometric detector; and a Perkin-Elmer 565 recorder. Acetonitrilewater (6535 or 60:40) was used as the eluent. The flow rate was 1mL/min, and the wavelength of the UV detector was 254 nm. Origin and Preparation of Environmental Samples. The four stack gas samples were from a waste incinerator. Two samples contained the gas phase only, and two samples contained both the gas phase and particles. Two acidic and two alkaline pulp mill effluents were originated from a softwood plant and a hardwood plant (C/D- and Environ. Sci. Technol., Vol. 27, No. 7, 1993 1318
Table 11. Exact Values of M+ and (M + 2)+ Ions Used in Selected-Ion Monitoring and Theoretical Relative Abundance Ratios of M+ and (M + 2)+ Ions
Table 1. Pulp Mill Effluent Samples and Dry Weights (mg/L) of Particles Filtered from Samples particle no.
sample
1
acid effluent, softword kraft (bleachingplant I), C-stage alkaline effluent, softwood kraft (bleachingplant l), E-stage acid effluent, hardwood kraft (bleachingplant 2), C-stage alkaline effluent, hardwood kraft (bleachingplant 2), E-stage input, activated sludge treatment plant output, activated sludge treatment plant
2 3 4 5
6
103
75
178
18
19
37
12
2
14
74
11
85
54
17
71
31
23
54
E-stages). The fifth effluent sample was an input of activated sludge treatment of combined effluents, and the sixth was an output of activated sludge treatment plant. Only particles in the effluent waters were studied. The origin of the effluent samples and the weight of the particles filtered from the 5-L effluent water samples are presented in Table I. The preparation of the samples has been explained earlier (IO,11,23). The model compounds were found to withstand washing by sulfuric acid and were chromatographed by basic aluminum oxide and activated carbon with the dioxin fraction.
.
napnet *Y:DBpec
PCDPS
M+
(M+ 2)+
M+/(M + 2)'
diCDPSs triCDPSs tetraCDPSs pentaCDPSs hexaCDPSs
253.9724 287.9334 321.8944 356.8655 389.8166
255.9695 289.9305 323.8915 357.8525 391.8136
1.442 0.987 0.760 0.606 0.507 ~
~
~~
G U M S Analysis of Model Compounds and Samples. A VG AutoSpec high.resolution mass spectrometer connected to a HP 5890 Series I1 gas chromatograph was used in the mass spectrometric analysis of the model compounds and the samples. The column was a 25-m HP-5 (0.2 m, 0.11 pm). The temperature program was 100 "C (1min) - 20 OC/min - 180 OC - 5 OC/min - 280 "C (15 min). The temperature of the injector was 260 O C , transfer line was 280 OC, and ion source waa 260 O C . The electron ionization potential was 36 eV. GC/MS full-scan (m/z50-500)E1 mass spectra were run for the two different reaction mixtures of chlorinated compounds. The samples were analyzed by selected-ion monitoring (SIM) GUMS with a resolution of 10000, and some samples were analyzed with a resolution of 20 OOO. The chlorinated compounds were monitored with the values of the M+ and (M + 2)+ ions. Table I1 presents the exact M+ and (M + 2)+ values used in the monitoring and the relative abundance ratios of the M+ and (M 2)+ ions.
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Flgure 1. Total Ion GC/MS chromatogram of the chlorlnatlon mixture of DPS (a) and full-scan E1 mass spectra of one (b) trC, (c) tetra-, and (d) pentaCDPS. 1320 Envlron. Scl. Technol., Vol. 27, No. 7, 1993
IAL-TKDPS CI
ps+& CI
i
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I
50
I 30
20
10
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Figure 2. HPLC chromatogram from the fractionatlon of DPS chlorination mixture; Silasorb C 8 SPH, acetonltrl1e:water (65:35) 1 mL/min. and UV = 254 nm.
'HNMR of Model Compounds. All IH and I3CNMR spectra were measured with a Jeol GSX 270 FT NMR spectrometer working at 270.2 and 67.8 MHz equipped with a C/H dual probe at 30 "C for dilute CD2Cl2 solutions. The lH NMR spectral settings were as follows: spectral width, 2800 Hz; number of data points, 32 000, giving a digital resolution of 0.17 Hz; flip angle, 8.4 ps (90'); acquisition time, 4 s; pulse delay, 1s; and number of scans, 40-1000. All FIDs were exponentially windowed by a linebroadening factor of digital resolution prior to Fourier transformation to improve the S/N in the frequency spectra. All chemical shifts 'are referenced to a solvent signal (5.3 ppm from tetramethylsilane, TMS). The 13C NMR spectral settings were as follows: spectral width, 10 000 Hz; number of data points, 32 000, giving a digital resolution of 0.6 Hz; flip angle, 8.8 ps (goo); acquisition time, 1.5 s; pulse delay, 5 s; and number of scans, 7000. All FIDs were exponentially windowed by a line-broadening factor of digital resolution prior to Fourier transformation to improve the S/N in the frequency spectra. All chemical shifts are referenced to a solvent signal (54.2 ppm from TMS). 'H NMR spectra were analyzed using a program MAOCON (24)in a VAX 4000 computer of the Computing Center, University of Jyviiskyla. Results Mass Spectrometry and HPLC of Model Compounds. The total ion GC/MS chromatogram of synthesis 1after 4-5 h of standing is presented in Figure la. The full-scan E1 mass spectra of a tri-, tetra-, and pentaCDPS isomer (Figure lb-d) all show an intense molecular ion peak. The molecular ion (M+)and the fragment ions show the typical clustering expected by chlorine isotopes. The
40
30
i 20 min
Flgure 8. HPLC chromatogram from the fractionation of Synthesis 2 (1,2dichlorobenzene sulfur) mixture; Silasorb C 8 SPH, acetonitrile: water (60:40) 1 mL/mln, and UV = 254 nm.
+
M+ (rnlz) for TriCDPSs is 288, for tetraCDPSs it is 324, and for pentaCDPSSs it is 358. A very strong fragmentation produced by the cleavage of two chlorines, M+ 2C1(70), can be seen in all spectra: 218,252, and 288 for tri-, tetra-, and pentaCDPSs, respectively. The mass spectra of some tri- and tetrachlorinated isomers were found to be very similar. It was possible to separate several PCDPS isomers by using reversed-phase HPLC. An HPLC chromatogram from the fractionation of the DPS chlorination mixture using a Silasorb C 8 SPH column and acetonitrile-water (65:35) a t 1mL/min of eluent is given in Figure 2. Three triCDPS isomers and two tetraCDPS isomers could be separated as pure compounds. Figure 3 describes the HPLC fractionation of synthesis 2 (1,2-dichlorobenzene sulfur) mixture. The full-scanE1mass spectraof fraction 1/2 (trichlorothianthrene) and fraction 4/2 are presented in Figure 4. 'H NMR of PCDPSs. The structure of the isomers was determined by lH NMR spectroscopy. The main products from synthesis 1(chlorination of DPS)were found to be 2,2',4,4'-tetraCDPS and 2,4,4'-triCDPS. Minor amounts of 2,4',6- and 2,2',4-triCDPS were formed, Figure 5. The ortho-para directing behavior of sulfur in electrophilic aromatic substitution seems to be predominant as expected. The main product from synthesis 2 was 3,3',4',4'tetraCDPS. Also another isomer of tetraCDPS, two trichlorothianthrenes and one tetrachlorothianthrene (not yet identified) were formed (Figure 6). The 'H NMR spectra were run from the fractions 111, 211,311, and 411 of the HPLC fractionation described in Figure 2 and from the fraction 5/2 of the HPLC fractionation described in Figure 3. Amounts of chlorines in these fractions are based on their mass spectra. The other fractions of this mixture gave IH NMR spectra, in which signallnoise was too low for a reliable spectral interpretation.
+
Environ. Sci. Technol., Vol. 27, No. 7, 1993 1321
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Figure 4. Full-scan E1 mass spectra of one (a) trlchlorothlanthrene and (b) tetrachlorothlanthreneisomer.
Tables I11 and IV show collected IH NMR chemical shifts and spin-spin coupling constants of five PCDPSs. The lH NMR spectral interpretation is based on the synthetical knowledge, viz., general directing rules, in electrophilic aromatic substitution reactions as well as comparisons between lH NMR spectra obtained for different isomers. A cornerstone in the present analysis was a comparison between the lH NMR spectra of the fractions 3/1 (triCDPS) and 4/1 (tetraCDPS) obtained from synthesis 1(see Figure 4) and the general knowledge of ortho- and para-directing properties of sulfur in electrophilic substitution of thiophenol or related structures. Interpretation of lH NMR Spectra of CDPSs. Comparison of Fractions 311 and 411 (Synthesis 1 ) . Based on the synthetic procedure, the expected positions 1322 Envlron. Scl. Technol., Vol. 27, No. 7, 1993
for the attack of the chlorine substituent(s) are ortho and para to the sulfur. By comparing the lH NMR spectra of fractions 3/1 and 4/1, it is easy to observe that one part of the 3/1 (triCDPS) spectrum is very similar to the spectrum of 4/1 (tetraCDPS). The simple structure of the 4/1 spectrum reveals that both of the rings in this tetrachloro derivative must be similar. The 411 spectrum consists of a AB quartet (J = 8.55 Hz),in which the less shielded side (6 = 7.21 ppm) is split into a doublet of 2.2 Hz. The same coupling is found in a separated doublet at 6 = 7.49 ppm. These two couplings are very typical between aromatic protons at ortho and meta positions with each other. There exist only three different isomeric dichlorinated phenyl rings, which could produce this observed pattern, viz., 2,4-, 2,5-,and 3,4-dichlorinatedones. Based on the synthetic procedure used, it is now concluded
5
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2AK-TrlCDPS
CI
main DrOdUCt
CI
CI
Cl
2A’.&TrlCDPS
2.2’A-TrlCDPS minor products
Flgure 5. Products from the chlorination of DPS with SO2C12.
that the correct structure is a symmetric bis(2,4-dichlorophenyl) sulfide. Based on spectral similarity, one of the rings in the 311 (triCDPS) fraction has to be 2,4-dichlorinated as in the 411 fraction. The remaining symmetric part of spectrum 311 is very typical for a para-substituted phenyl ring. This means that the third chlorine substituent should locate at position 4l or para to sulfur. By a computer-based iteration, this AzBz pattern could be reproduced exactly the same as it was observed. Thus, the fraction 311 is 2,4,4’-triCDPS. Fraction 211 (triCDPS) exhibits a similar AB quartet as fractions 311 and 411 revealing the presence of a 2,4dichlorinated ring. The other part of the 211 spectrum consists of very complex and strongly overlapping signals, which could not be analyzed by a computer. The lack of more than one strong doublet with a coupling of ca. 2 Hz in the 211 spectrum reveals that all four protons must be in adjacent positions. Consequently, the third chlorine should locate at 2l position. Thus, this fraction is 2,2’,4triCDPS. Fraction 111 (triCDPS) shows a doublet (6 = 7.46 ppm) and a triplet (6 = 7.30) with the same coupling ( J = 8.24 Hz)typical of an AB2 spin system. This can be originated only from 2,6-dichlorinated phenyl moiety with three adjacent protons. The rest of the spectrum again is a characteristic A2B2 pattern originated from a parasubstituted phenyl ring. A computer-based iteration reproduced the observed pattern exactly. Large differences in the chemical shifts of the A2B2 patterns between the 111and 311 fractions can be explained Table 111. proton no.
minor products
Flgure 6. Productsfrom the synthesis starting from 1,2dichkrobenzene and sulfur.
by the steric effects and changed conformational preferences induced by the diortho-substitution in the 111 fraction. AlllH NMR spectral details observed with the fractions obtained from syntheis 1support the hypothesis that in this procedure the positions ortho and para to the sulfur are strongly preferred for the attack of chlorine substituents. Fraction 512 (tetraCDPS, Synthesis 2) again shows a very simple spectrum consisting of an AB quartet (6 = 7.40 and 7.32), in which the more shielded side is split by a coupling (J = 2.14 Hz).The same coupling is also found in a doublet (6 = 7.57). The 512 spectrum differs greatly from that one of the 411 fraction, although their spin systems are similar. As stated above, only three alternatives exist for a symmetrical tetraCDPS with this kind of spin system. Therefore, for the 512 fraction only two isomers,bis (3,4-dichlorophenyl)or bis (2,5-dichlorophenyl) sulfide, are possible. Based on the synthetic procedure, viz., that the only starting material was ortho-dichlorobenzene with adjacent substituents, it is very improbable that the synthesis product could be the 2,bdichlorinated derivative. Thus, the 512 fraction must be bis(3,4dichlorophenyl) sulfide. This conclusion is supported by the general knowledge concerning the directing properties of chlorine substituents in aromatic electrophilic substitution reactions. Owing to the steric reasons, however,
NMR Chemical Shifts (ppm from TMS)of Five PCDPSs Measured for CDzClz Solutions at 30 OC 2
3
4
5
6
G(’H)/ppm 2f
3/
4‘
5/
6’
DPS
6.90 1.23 7.00 7.23 6.90 6.90 7.23 7.00 7.23 6.90(28) 2,4’,6-triC 7.46 7.30 7.46 7.06 7.21 7.21 7.06 a 2,2’,4-triC 7.48 7.18 7.03 2,4,4’-triC 7.43 7.14 6.97 7.33 7.34 7.34b 7.336 2,2’,4,4’-tetraC 7.49 7.21 7.08 1.49 7.21 7.08 3,3’,4,4/-tetraC 7.57 7.40 7.32 7.57 7.40 1.32 Values are missing, because this ring gave a complex spectrum, which partly overlappedwith the signals originatedfrom the 2,4-substituted ring. Assignation can be interchanged. Environ. Sci. Technol., Vol. 27, No. 7,
lgg3
1323
Table V. 13C NMR Chemical Shifts for 2,4-Dichlorinated and 4Whlorinated Rings of Compund 3/1
Table IV. "J(R,EI)Coupling Constants (Hz) of Five PCDPSs Measured for CDzClz Solutions at 30 OC J/Hz protons
2,3
2,4
2,5
2,6
3,4
carbon no.
3,5
3,6
4,5
4,6
5,6
7.87 1.26 0.59 1.94 7.41 1.75 0.59 7.41 1.26 1.87 8.24 8.24 2,4',6 8.60 2,4',6 8.60 2.72 3.10 2.20 8.75 2,2',4 2'-substituted ring is not analyzed 2,2',4 2.22 8.55 2,4,4' 8.47 2,4,4' 8.47 2.03 2.03 8.55 2.30 bis(2,4) 8.39 2.28 bis(3,4)
DPS
the ortho positions to chlorines in ortho-dichlorobenzene are hindered for the attack by sulfur. Therefore, the 3,4dichlorinated derivative is predominant over the 2,3dichlorinated one. 13CNMR of PCDPSs. '3CNMRspectrum of DPS has been assigned in the literature (21). The chemical shifts measured during the present work for 0.5 M CD2Cl2 solution are [the literature values are given in parentheses (2111 as follows: 136.7 (135.8) (i), 131.9 (130.9) (01, 130.1 (129.1) (m), and 127.9 (126.9) (p) ppm, respectively. The chlorine substituent chemical shifts (SCS) calculated by subtracting the 13CNMR chemical shifts of benzene and chlorobenzene (ref 21, p 256) are 6.4 (i),O.2 (o), 1.0 (m),and -2.0 (p) ppm, respectively. These SCSs are used in calculating the 13C NMR chemical shifts for 2,4-dichlorinated and 4'-chlorinated rings of compound 311 and are presented in Table V. As can be seen, the calculated and observed 13CNMR chemical shifts are the same within the accuracy of 1ppm. The only exception forms carbons 2 and 6 in the 4'289.9305
1
DPS
obs 2,4-diC calc 2,4-diC obs 4'4 C ~ 4'4 obs
2
136.7 134.9 135.4 C 134.7 not obs
3
131.9 139.3 138.2 132.9 134.9
4
130.1 127.9 130.5 135.3 130.5 notobs 130.3 134.3 130.6 notobs
5
6
130.1 128.3 128.5 130.3 130.6
131.9 133.9 132.4 132.9 134.9
substituted ring, where the difference is 2 ppm. This discrepancy probably is due to the vicinity of sulfur and the incapability of single substituent effects to take into account the mutual effect of sulfur and chlorine. Based on the intensities of the 13C NMR spectrum of the 3/1 fraction, the above conclusion can be verified. Namely, there exist two groups of protonated carbons characterized by different intensities. The intensity of two lines at 134.9 and 130.6 ppm is twice that of lines at 132.4, 130.5, and 128.5 ppm. The first group is originated from the CzV symmetric 4'-chlorinated ring, and the second group is from the unsymmetric 2,4-dichlorinated one, respectively. "J(H,H)coupling constants are collected in Table IV. They show very typical values for intraaromatic couplings, which can be used as an aid in spectral assignment. The presence of interring couplings have not been observed. Mass Spectrometry of Environmental Samples. All the environmental samples were analyzed with SIM technique with the values of M+ and (M 2)+ ions. All the pulp mill effluent samples, except sample 3, were found to contain at least one triCDPS isomer. The triCDPS model compounds could not all be completely resolved in the GUMS, so the structures of the triCDPSs of the samples could not be determined unambiguously. Three
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+ 2)+ ions of (a) trlCDPSs (289.9305) and (b) tetraCDPSs (323.8915) from pulp mill effluent sample
Envlron. Sci. Technol., Vol. 27, No. 7, 1993
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+ 2)+ Ions of (a) tetraCDPSs (323.8915) and of (b) PeCDPSs (357.8525) from a stack gas sample.
known triCDPS had GC/MS retention times of 26:20 rnin (2,4/,6-triCDPS), 26:17 rnin (2,2’,4-triCDPS), and 26:25 min (2,4,4’-triCDPS). The triCDPS found in the pulp mill effluent samples had a retention time in the area 26: 25-26:28 min. It seems to be the 2,4,4’-triCDPS isomer that is the main product in the sulfuryl chloride chlorination of DPS. The two known tetraCDPSs had the following retention times in GUMS: 2806 min (2,2’,4,4’tetraCDPS) and 28:36 min (3,3/,4,4’-tetraCDPS). No tetraCDPSs were found in the pulp mill effluent samples. One example from the GC/MS chromatograms is presented in Figure 7. The existence of the triCDPSs in the pulp mill effluent samples was verified by increasing the resolution of the MS to more than 20 000. The same peaks with the correct M+/(M + 2)+ ratio (less than 10% deviation from theoretical values) could still be found. Two of the four stack gas samples contained some triand tetraCDPSs. Several samples gave peaks also with the ions 355.8555, 357.8525, 389.8165, and 391.8135 used to screen the occurrence of penta- and hexaCDPSs, but the M+/(M + 2)+ ratios calculated did not correspond to these congeners. Figure 8 describes the GC/MS chromatograms (different GC temperature program) of astack gas sample with the (M + 2)+ ions of tetraCDPSs (323.8915) and pentaCDPSs (357.8525). Conclusions
‘HNMR spectroscopy offers an excellent method in differentiating the PCDPSs. With the present technique, the structures of DPS derivatives can be solved at the microgram level. By using CD2C12as a solvent, it is possible to detect aryl protons without solvent interferences. Based on the synthetical knowledge and comparison of IH NMR spectra of HPLC fractionated isomers and
congeners of PCDPSs, it was possible to determine structures of five derivatives, viz., 2,2‘,4-, 2,4,4’-, and 2,4’,6triCDPSs as well as 2,2‘,4,4’- and 3,3’,4,4’-tetraCDPSs. The amount of 2,4,4’-triCDPS was enough for the 13C NMR spectrum. Its chemical shifts can be assigned by using chlorine-induced single substituent chemical shifts. Isomer-specific structure elucidation is of extreme importance in estimating the synthesis routes and optimizing the selectivity and in directing the effects in aromatic substitution reactions. To assist environmental analysis, it is necessary to produce a larger number of different pure isomers that can be used as model substances, thus enabling the identification of the exact structures of the isomers found in the samples. The toxicity of the PCDPSs is not yet known, but due to their structural similarity with polychlorinated diphenyl ethers, these compounds are suspected to be harmful compounds in our environment. Preparation of new PCDPS compounds and toxicological investigations of the PCDPSs are under progress. Acknowledgments
Mr. R. Kauppinen is thanked for his help in running the NMR spectra. Mr. Philip Lewis, University of Kent, Kent, U.K., is acknowledged for checkingthe English usage in the manuscript. M.Sc. Leena Welling from Institute for Environmental Research, University of Jyviiskyll, is thanked for the stack gas fractions. Literature Cited (1) Karcher, W.; Nelen, A.; Depaus, R.; van Eijk, J.; Glaude, P.; Jacob, J. InPolynuclear Aromatic Hydrocarbons: Chemical Analysis and Biological Fate; Cooke, M., Dennis, R., Eds.; Battelle Press: Columbus, OH, 1981; pp 317-327. (2) Eastmond, A.; Booth, G. M.; Lee, M. L. Arch. Enuiron. Contam. Toxicol. 1984,13, 105. Environ. Sci. Technol., Vol. 27, No. 7, 1993 1325
(3) Arpino, P. J.; Ignatiadis, I.; De Rycke, G. J. Chromatogr. 1987,390,329. (4) Berthou, F.; Dreano, Y. HRC & CC, J. High Resolut. Chromatogr. Chromatogr. Commun. 1988,11, 706. (5) Sinkkonen, S . Ph.D. Dissertation, University of Jyviiskyla, Finland, 1989. (6) Anderson, J. T.; Bobinger, S. Chemosphere 1992,24, 383. (7) Sinkkonen, S.; Koistinen, J. Chemosphere 1990,21, 1161. (8) Sinkkonen, S.; Kolehmainen, E.; Koistinen, J. Int. J. Environ. Anal. Chem. 1992, 47, 7. (9) Sinkkonen, S.; Kolehmainen, E.; Laihia, K.; Koistinen, J.
Int. J . Enuiron. Anal. Chem., in press. (10) Sinkkonen, S.; Paasivirta, J.; Koistinen, J.; Tarhanen, J. Chemosphere 1991,23, 583. (11) Sinkkonen, S.; Paasivirta, J.; Koistinen, J.; Lahtipera, M.; Lammi, R. Chemosphere 1992,24, 1755. (12) Buser, H.-R.; Dolezar, I. S.; Wolfensberger, M.; Rappe, C. Enuiron. Sci. Technol. 1991,25, 1637. (13) Buser, H.-R.; Rappe, C. Anal. Chem. 1991, 63, 1210. (14) M b t y l l , E.; Ahotupa, M.; Nieminen, L.; Paasivirta, J.; Sinkkonen, S. Dioxin '92; 12th International Symposium on Dioxins and Related Compounds, Aug 24-28, 1992,
Tampere; Finnish Institute of Occupational Health: Helsinki, 1992; Vol. 10, pp 161-163.
1326
Envlron. Sci. Technol., Vol. 27,
No. 7, 1993
(15) Kuehl, D. W.; Butterworth, B. C.; DeVita, W. M.; Sauer, C. P. Biomed. Environ. Mass Spectrom. 1987, 14, 443. (16) Rogers, I. H.; Levings, D. C.; Lockhart, W. L.; Norstrom, R. J. Chemosphere 1989, 19, 1853. (17) Nevalainen, T.; Kolehmainen, E.; Rissanen, K.; Stiffm&nen, M.-L.; Kauppinen, R. Magn. Reson. Chem. 1993,31,100,
and references cited therein. (18) LlabrBs, G.; Baiwir, M.; Christiansens, L.; Piette, J.-L. Can. J. Chem. 1979,57, 2967. (19) Chandrasekaran,R.; Perumal, S.;Wilson, D. A. Magn. Reson. Chem. 1987,25,1001. (20) Ogawa, S.; Mataunaga, Y.; Sato, S.; Erata, T.; Furukawa, N. Tetrahedron Lett. 1992, 33, 93. (21) Breitmaier, E.; Voelter, W. Carbon-13 NMR Spectroscopy; 3rd ed.; VCH Verlagsgesellschaft: Weinheim, 1987; p 257. (22) Buckholtz, H. E.; Bose, A. C.; Graham, J. C. U.S. Patent 3 989 715, 1976. (23) Koistinen, J.; Paasivirta, J.; Stirkka, J. Chemosphere 1990, 21, 1371. (24) Laatikainen, R. J. Magn. Reson. 1977, 27, 169.
Received for review August 1 1 , 1992. Revised manuscript received December 7, 1992. Accepted March 25, 1993.
