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Synthesis and Surfactant Properties of Novel Fluoroalkylated 4-Vinylpyridinium Chloride Oligomers
JOURNAL OF COLLOID AND INTERFACE SCIENCE ARTICLE NO.
178, 379–381 (1996)
0131
LETTER TO THE EDITOR Synthesis and Surfactant Properties of Novel Fluoroalkylated 4-Vinylpyridinium Chloride Oligomers
New perfluoropropylated and perfluoro-oxaalkylated 4-vinylpyridinium chloride oligomers with carbon – carbon bond formation were prepared by the reactions of the corresponding fluoroalkanoyl peroxides with 4-vinylpyridinium chloride in excellent to moderate yields under very mild conditions. These fluorinated oligomers were effective for reducing the surface tension of water to around 10 mN m01 with a break point resembling a CMC ( critical micelle concentration ) , and are applicable to new fluorinated cationic oligosurfactants. q 1996 Academic
N-oxide oligomers were obtained as the reaction products as illustrated in the scheme
Press, Inc.
Key Words: fluoroalkylated pyridinium oligomers; surface tension; cationic surfactants; fluoroalkanoyl peroxides.
Recently, hydrophobically modified polyelectrolytes ( polysoaps or micellar polymers ) have been receiving increasing attention owing to their high potential in various industrial, biological, and environmental applications ( 1 ) . Physicochemical behavior of polysoaps, especially cationic polysoaps such as quaternized poly ( 4-vinylpyridines ) ( 2 ) and poly ( alkylmethyldiallylammonium bromides ) ( 3 ) have been studied in detail. Recent attention has been also focused on the interactions involving cationic polysoaps and surfactants in aqueous solutions as model systems for understanding biological binding processes ( 3 ) , and these cationic polysoaps are known to form hydrophobic microdomains in aqueous solution ( 2, 3 ) . In general, studies of the synthesis and properties of various polysoaps have been mainly concentrated on hydrocarbons. In contrast, the exploration of fluoroalkylated polysoaps ( polyelectrolytes modified by fluoroalkyl segments ) with not ester or amide but carbon – carbon bond formation has hitherto been limited, owing to the direct introduction of fluoroalkyl groups into organic molecules being not so easy. However, these fluoroalkylated compounds have been the subjects of considerable research of both a fundamental and applied nature. We have been actively studying the reaction behaviors of various of fluoroalkanoyl peroxides ( 4 ) , and we have succeeded in preparing a series of vinylsilane ( 5 ) , acrylic acid ( 6 ) , allyl alcohol ( 7 ) , and vinyl alcohol ( 8 ) oligomers containing two fluoroalkyl end-groups by using fluoroalkanoyl peroxides as key materials. It is of much interest to synthesize novel polysoaps ( oligomeric soaps or oligosoaps ) with fluoroalkanoyl peroxides. In this Letter, we report the synthesis and surfactant properties of novel fluorinated cationic oligosoaps: fluoroalkylated 4-vinylpyridinium chloride oligomers by using fluoroalkanoyl peroxides. First, we tried to prepare directly fluoroalkylated 4-vinylpyridine oligomers from the reactions of 4-vinylpyridine with fluoroalkanoyl peroxides. We were not able to isolate the expected oligomers; however, not only 4-vinylpyridine N-oxide but also fluoroalkylated 4-vinylpyridine
Previously, we reported that styrene reacts with fluoroalkanoyl peroxides to afford not the radical polymerizable products but 1:1 adducts [PhCH(OCORF )CH2RF ] via a single electron transfer from styrene to peroxide (9). The formation of 4-vinylpyridine N-oxide means that the nucleophilic attack of an N-lone pair of 4-vinylpyridine on an O–O bond of peroxide should be more preferential than an electron transfer reaction from 4-vinylpyridine to peroxide as observed in the reaction with styrene. We have already reported a similar nucleophilic attack of an N-lone pair of pyridine on an O–O bond of fluoroalkanoyl peroxide (10). On the other hand, it is considered that fluoroalkylated 4-vinylpyridine N-oxide oligomers would be obtained by the oligomerization of 4-vinylpyridine N-oxide with fluoroalkanoyl peroxides. Thus, we tried to react fluoroalkanoyl peroxides with 4-vinylpyridinium chloride which has no nucleophilic property. As shown in the following scheme, the oligomerization of 4-vinylpyridine with various fluoroalkanoyl peroxides was found to proceed under very mild conditions to afford the expected fluoroalkylated 4-vinylpyridinium chloride oligomers in excellent to moderate isolated yields:
A typical experiment for the synthesis of fluoroalkylated 4-vinylpyridinium chloride oligomers is as follows. Perfluoro-2,5-dimethyl-3,6-dioxanonanoyl peroxide (3 mmol) in 1,1,2-1,2,2-trichlorotrifluoroethane (39 g) was added to the aqueous solution (50%, w/w) of 4-vinylpyridinium chloride (8 mmol). The heterogeneous solution was stirred vigorously at 457C for 5 h under nitrogen. After evaporating the solvent, the obtained crude product was reprecipitated from water–tetrahydrofuran to give bis(perfluoro-1,4dimethyl-2,5-dioxaoctylated) 4-vinylpyridinium chloride oligomers (1.38
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0021-9797/96 $18.00 Copyright q 1996 by Academic Press, Inc. All rights of reproduction in any form reserved.
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LETTER TO THE EDITOR
TABLE 1 Reactions of Fluoroalkanoyl Peroxides with 4-Vinylpyridinium Chloride (4-VPC) RF –(4-VPC)n –RF RF in peroxide (mmol) C3F7 4 CF(CF3)OC3F7 2 CF(CF3)OCF2CF(CF3)OC3F7 5 3 2 2 CF(CF3)OCF2CF(CF3)OCF2CF(CF3)OC3F7 4 a
4-VPC (mmol)
Yield (%)a
Mn (Mw/Mn)
12
43
10400 (4.38)
17
74
7010 (2.47)
8 8 12 18
7 36 38 68
5090 2850 6800 6250
12
40
4700 (1.93)
(1.27) (1.80) (2.33) (2.77)
The yields are based on the starting materials [4-vinylpyridinium chloride and the decarboxylated peroxide unit (RF –RF)].
g). This oligomer showed the following spectral data: IR n (cm01 ) 3051, 1508 (NH), 1350 (CF3 ), 1242 (CF2 ); 1H NMR (D2O) d 1.44–2.25 (CH2 ), 2.55–2.85 (CH), 7.26–7.78 (aromatic protons, 2H), 8.25–8.65 (aromatic protons, 2H); 19F NMR (D2O, ext. CF3CO2H) d 01.0– 06.4 (26F), 044.8 (6F), 070.0 (2F); average molar mass (Mn) Å 2850, Mw/Mn Å 1.80 (determined by gel permeation chromatography calibrated with standard poly(ethylene glycol) by using 30% acetonitrile solution containing 0.2 M acetic acid and 0.2 M sodium acetate as the eluent). Other perfluorooxaalkylated and perfluoropropylated 4-vinylpyridinium chloride oligomers were obtained under similarly mild conditions. These results were listed in Table 1.
FIG. 1. Surface tension of aqueous solution of RF – (VPC)n – RF : s, RF Å C3F7 ; Mn Å 10400; l, RF Å CF(CF3 )OC3F7 ; Mn Å 7010; h, RF Å CF(CF3 )OCF2CF(CF3 )OC3F7 ; Mn Å 6800.
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In the reactions of 4-vinylpyridinium chloride with peroxides, we could not isolate the 1:1 adduct with a single electron transfer reaction at all as well as the case of styrene ( 11 ) . However, as shown in Table 1, it was clarified that not only perfluoropropylated but also perfluorooxaalkylated 4-vinylpyridinium chloride oligomers were obtained in similar isolated yields under mild conditions. The oligomerization of 4vinylpyridinium chloride with fluoroalkanoyl peroxides was considered to proceed via a primary radical termination or a radical chain transfer to the peroxide under our oligomeric conditions, in which the concentration of the peroxide was almost the same as that of 4-VPC ( molar ratio of 4-VPC / peroxide Å 2 – 9 ) , to afford mainly oligomers containing two fluoroalkylated end-groups. Fluoroalkylated 4-vinylpyridinium oligomers thus obtained were easily soluble in water and methanol. The surface properties of these new cationic oligomers were evaluated by measuring the surface tension of aqueous solutions by the Wilhelmy plate method at 307C. As shown in Fig. 1, the degree of reduction in surface tension of water depends on the length of fluoroalkyl groups in oligomers as well as the usual fluorinated surfactants ( 12 ) ; perfluoro-oxaalkylated oligomers were more effective for reducing the surface tension of water to around 10 mN m01 than those perfluoropropylated. Thus, these fluoroalkylated cationic oligomers were found to become novel high-molecular-mass surfactants which can reduce the surface tension of water effectively. Interestingly, these oligomers were clarified to possess a break point resembling a CMC ( critical micelle concentration ) and to be useful as new fluorinated oligosoaps, although hydrocarbon polysoap solutions are well known to not exhibit a CMC or a break point resembling a CMC ( 13 ) . This finding is considered to be a unique future in these fluoroalkylated oligomeric surfactants. In particular, each break point of perfluoro-oxaalkylated oligomers is likely to be observed in oligomer content ( ca. 0.5 g dm03 ) lower than that of perfluoropropylated oligomers. A particular future of our fluorinated oligomers in aqueous solutions cannot be explained in detail at the present time; however, these oligomers are suggested to form the intra- or intermolecular aggregates in aqueous solutions owing to exhibiting a clear break point resembling a CMC. Very recently, we have also found that fluoroalkyl end-capped allyl- and diallylammonium chloride oligomers are effective for reducing the surface tension of water to around 10 mN m01 , and a break point resembling a CMC is observed in their solutions ( 14 ) . In addition, we succeeded in preparing perfluoro-oxaalkylated 4-vinylpyridine oligomers in 34% [RF Å CF(CF3 )OC3F7 ] and 45% [RF Å
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LETTER TO THE EDITOR CF(CF3 )OCF2CF(CF3 )OC3F7 ] isolated yields by the reactions of the corresponding 4-vinylpyridinium chloride oligomers with aq. KOH as in the scheme
These fluoroalkylated 4-vinylpyridine oligomers were not soluble in water, but soluble in polar solvents such as methanol, ethanol, and N,N-dimethylformamide. Especially, these oligomers are expected to become useful precursors for preparing various fluoroalkylated 4-vinylpyridine oligomers quaternized by long alkyl groups. In this way, our new fluoroalkylated pyridinium oligomers were clarified to exhibit unique properties imparted by fluorine, although these compounds are fluoroalkyl end-capped hydrocarbon oligomers where fluoroalkyl segments were introduced into only two end-sites in one oligomer. Further studies of the synthesis and properties of cationic oligomers with fluoroalkanoyl peroxides are now actively in progress.
8. Sawada, H., Yamaguchi, K., Mitani, M., Nakajima, H., Nishida, M., and Moriya, Y., Polymer 35, 444 (1994). 9. Yoshida, M., Moriya, K., Sawada, H., and Kobayshi, M., Chem. Lett. 755 (1985). 10. Sawada, H., Yoshida, M., Hagii, H., Aoshima, K., and Kobayashi, M., Bull. Chem. Soc. Jpn. 59, 215 (1986). 11. This finding indicates that an interaction between the HOMO energy level of 4-VPC ( 014.017 eV; calculated value with MNDO-PM3 semiemprical MO method: Stewart, J. J. P., and Fujitsu Ltd. MOPAC 93, Tokyo, Japan) and LUMO (peroxide) weaker than that of 4-vinylpyridine ( 09.688 eV) or styrene ( 09.132 eV) causes a new interaction between HOMO (4-VPC) and SOMO of the fluoroalkyl radical (RFr) to derive not an electron transfer from 4-VPC to peroxide but an usual radical oligomerization. 12. Abe, M., Morikawa, K., Ogino, K., Sawada, H., Matsumoto, T., and Nakayama, M., Langmuir 8, 763 (1992). 13. Anton, P., Koberle, P., and Laschewsky, A., Makromol. Chem. 194, 1 (1993). 14. Sawada, H., Tanba, K.-I., Oue, M., Kawase, T., Hayakawa, Y., Mitani, M., Minoshima, Y., Nishida, M., and Moriya, Y., Polymer 36, 2103 (1995). HIDEO SAWADA * ,1 ATSUHITO WAKE * MASATOSHI OUE * TOKUZO KAWASE† YOSHIO HAYAK AWA‡ YOSHIHIRO MINOSHIMA§ MOTOHIRO MITANI§
REFERENCES 1. Dubin, P. B. (Ed.), ‘‘Microdomains in Polymer Solutions.’’ Plenum, New York, 1986. 2. Shinkai, S., Hirakawa, S., Shimomura, M., and Kunitake, T., J. Org. Chem. 46, 868 (1981). 3. (a) Wang, G.-J., and Engberts, J. B. F. N., Langmuir 10, 2583 (1994); (b) Yang, Y.-J., and Engberts, J. B. F. N., J. Org. Chem. 56, 4300 (1991). 4. (a) Sawada, H., J. Fluorine Chem. 61, 253 (1993); (b) Sawada, H., ‘‘Reviews on Heteroatom Chemistry’’ (S. Oae, Ed.), Vol. 8, p. 205. Myu, Tokyo, 1993; (c) Sawada, H., Matsumoto, T., and Nakayama, M., Yuki Gosei Kagaku Kyokaishi 50, 592 (1992). 5. Sawada, H., and Nakayama, M., J. Chem. Soc. Chem. Commun. 677 (1991). 6. Sawada, H., Gong, Y.-F., Minoshima, Y., Matsumoto, T., Nakayama, M., Kosugi, M., and Migita, T., J. Chem. Soc. Chem. Commun. 537 (1992). 7. Sawada, H., Tanba, K., Oue, M., Kawase, T., Mitani, M., Minoshima, Y., Nakajima, H., Nishida, M., and Moriya, Y., Polymer 35, 4028 (1994).
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*Department of Chemistry Nara National College of Technology Yata, Yamatokoriyama, Nara, 639-11, Japan †Faculty of Science of Living Osaka City University Sugimoto, Sumiyoshi-ku, Osaka, 558, Japan ‡National Industrial Research Institute of Nagoya Kita-ku, Nagoya, 462, Japan §Tsukuba Research Laboratory NOF Corporation Tokodai, Tsukuba, Ibaraki, 300-26, Japan Received March 30, 1995; accepted September 22, 1995 1
To whom correspondence should be addressed.
coidas
AP: Colloid
178, 379–381 (1996)
0131
LETTER TO THE EDITOR Synthesis and Surfactant Properties of Novel Fluoroalkylated 4-Vinylpyridinium Chloride Oligomers
New perfluoropropylated and perfluoro-oxaalkylated 4-vinylpyridinium chloride oligomers with carbon – carbon bond formation were prepared by the reactions of the corresponding fluoroalkanoyl peroxides with 4-vinylpyridinium chloride in excellent to moderate yields under very mild conditions. These fluorinated oligomers were effective for reducing the surface tension of water to around 10 mN m01 with a break point resembling a CMC ( critical micelle concentration ) , and are applicable to new fluorinated cationic oligosurfactants. q 1996 Academic
N-oxide oligomers were obtained as the reaction products as illustrated in the scheme
Press, Inc.
Key Words: fluoroalkylated pyridinium oligomers; surface tension; cationic surfactants; fluoroalkanoyl peroxides.
Recently, hydrophobically modified polyelectrolytes ( polysoaps or micellar polymers ) have been receiving increasing attention owing to their high potential in various industrial, biological, and environmental applications ( 1 ) . Physicochemical behavior of polysoaps, especially cationic polysoaps such as quaternized poly ( 4-vinylpyridines ) ( 2 ) and poly ( alkylmethyldiallylammonium bromides ) ( 3 ) have been studied in detail. Recent attention has been also focused on the interactions involving cationic polysoaps and surfactants in aqueous solutions as model systems for understanding biological binding processes ( 3 ) , and these cationic polysoaps are known to form hydrophobic microdomains in aqueous solution ( 2, 3 ) . In general, studies of the synthesis and properties of various polysoaps have been mainly concentrated on hydrocarbons. In contrast, the exploration of fluoroalkylated polysoaps ( polyelectrolytes modified by fluoroalkyl segments ) with not ester or amide but carbon – carbon bond formation has hitherto been limited, owing to the direct introduction of fluoroalkyl groups into organic molecules being not so easy. However, these fluoroalkylated compounds have been the subjects of considerable research of both a fundamental and applied nature. We have been actively studying the reaction behaviors of various of fluoroalkanoyl peroxides ( 4 ) , and we have succeeded in preparing a series of vinylsilane ( 5 ) , acrylic acid ( 6 ) , allyl alcohol ( 7 ) , and vinyl alcohol ( 8 ) oligomers containing two fluoroalkyl end-groups by using fluoroalkanoyl peroxides as key materials. It is of much interest to synthesize novel polysoaps ( oligomeric soaps or oligosoaps ) with fluoroalkanoyl peroxides. In this Letter, we report the synthesis and surfactant properties of novel fluorinated cationic oligosoaps: fluoroalkylated 4-vinylpyridinium chloride oligomers by using fluoroalkanoyl peroxides. First, we tried to prepare directly fluoroalkylated 4-vinylpyridine oligomers from the reactions of 4-vinylpyridine with fluoroalkanoyl peroxides. We were not able to isolate the expected oligomers; however, not only 4-vinylpyridine N-oxide but also fluoroalkylated 4-vinylpyridine
Previously, we reported that styrene reacts with fluoroalkanoyl peroxides to afford not the radical polymerizable products but 1:1 adducts [PhCH(OCORF )CH2RF ] via a single electron transfer from styrene to peroxide (9). The formation of 4-vinylpyridine N-oxide means that the nucleophilic attack of an N-lone pair of 4-vinylpyridine on an O–O bond of peroxide should be more preferential than an electron transfer reaction from 4-vinylpyridine to peroxide as observed in the reaction with styrene. We have already reported a similar nucleophilic attack of an N-lone pair of pyridine on an O–O bond of fluoroalkanoyl peroxide (10). On the other hand, it is considered that fluoroalkylated 4-vinylpyridine N-oxide oligomers would be obtained by the oligomerization of 4-vinylpyridine N-oxide with fluoroalkanoyl peroxides. Thus, we tried to react fluoroalkanoyl peroxides with 4-vinylpyridinium chloride which has no nucleophilic property. As shown in the following scheme, the oligomerization of 4-vinylpyridine with various fluoroalkanoyl peroxides was found to proceed under very mild conditions to afford the expected fluoroalkylated 4-vinylpyridinium chloride oligomers in excellent to moderate isolated yields:
A typical experiment for the synthesis of fluoroalkylated 4-vinylpyridinium chloride oligomers is as follows. Perfluoro-2,5-dimethyl-3,6-dioxanonanoyl peroxide (3 mmol) in 1,1,2-1,2,2-trichlorotrifluoroethane (39 g) was added to the aqueous solution (50%, w/w) of 4-vinylpyridinium chloride (8 mmol). The heterogeneous solution was stirred vigorously at 457C for 5 h under nitrogen. After evaporating the solvent, the obtained crude product was reprecipitated from water–tetrahydrofuran to give bis(perfluoro-1,4dimethyl-2,5-dioxaoctylated) 4-vinylpyridinium chloride oligomers (1.38
379
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0021-9797/96 $18.00 Copyright q 1996 by Academic Press, Inc. All rights of reproduction in any form reserved.
coidas
AP: Colloid
380
LETTER TO THE EDITOR
TABLE 1 Reactions of Fluoroalkanoyl Peroxides with 4-Vinylpyridinium Chloride (4-VPC) RF –(4-VPC)n –RF RF in peroxide (mmol) C3F7 4 CF(CF3)OC3F7 2 CF(CF3)OCF2CF(CF3)OC3F7 5 3 2 2 CF(CF3)OCF2CF(CF3)OCF2CF(CF3)OC3F7 4 a
4-VPC (mmol)
Yield (%)a
Mn (Mw/Mn)
12
43
10400 (4.38)
17
74
7010 (2.47)
8 8 12 18
7 36 38 68
5090 2850 6800 6250
12
40
4700 (1.93)
(1.27) (1.80) (2.33) (2.77)
The yields are based on the starting materials [4-vinylpyridinium chloride and the decarboxylated peroxide unit (RF –RF)].
g). This oligomer showed the following spectral data: IR n (cm01 ) 3051, 1508 (NH), 1350 (CF3 ), 1242 (CF2 ); 1H NMR (D2O) d 1.44–2.25 (CH2 ), 2.55–2.85 (CH), 7.26–7.78 (aromatic protons, 2H), 8.25–8.65 (aromatic protons, 2H); 19F NMR (D2O, ext. CF3CO2H) d 01.0– 06.4 (26F), 044.8 (6F), 070.0 (2F); average molar mass (Mn) Å 2850, Mw/Mn Å 1.80 (determined by gel permeation chromatography calibrated with standard poly(ethylene glycol) by using 30% acetonitrile solution containing 0.2 M acetic acid and 0.2 M sodium acetate as the eluent). Other perfluorooxaalkylated and perfluoropropylated 4-vinylpyridinium chloride oligomers were obtained under similarly mild conditions. These results were listed in Table 1.
FIG. 1. Surface tension of aqueous solution of RF – (VPC)n – RF : s, RF Å C3F7 ; Mn Å 10400; l, RF Å CF(CF3 )OC3F7 ; Mn Å 7010; h, RF Å CF(CF3 )OCF2CF(CF3 )OC3F7 ; Mn Å 6800.
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In the reactions of 4-vinylpyridinium chloride with peroxides, we could not isolate the 1:1 adduct with a single electron transfer reaction at all as well as the case of styrene ( 11 ) . However, as shown in Table 1, it was clarified that not only perfluoropropylated but also perfluorooxaalkylated 4-vinylpyridinium chloride oligomers were obtained in similar isolated yields under mild conditions. The oligomerization of 4vinylpyridinium chloride with fluoroalkanoyl peroxides was considered to proceed via a primary radical termination or a radical chain transfer to the peroxide under our oligomeric conditions, in which the concentration of the peroxide was almost the same as that of 4-VPC ( molar ratio of 4-VPC / peroxide Å 2 – 9 ) , to afford mainly oligomers containing two fluoroalkylated end-groups. Fluoroalkylated 4-vinylpyridinium oligomers thus obtained were easily soluble in water and methanol. The surface properties of these new cationic oligomers were evaluated by measuring the surface tension of aqueous solutions by the Wilhelmy plate method at 307C. As shown in Fig. 1, the degree of reduction in surface tension of water depends on the length of fluoroalkyl groups in oligomers as well as the usual fluorinated surfactants ( 12 ) ; perfluoro-oxaalkylated oligomers were more effective for reducing the surface tension of water to around 10 mN m01 than those perfluoropropylated. Thus, these fluoroalkylated cationic oligomers were found to become novel high-molecular-mass surfactants which can reduce the surface tension of water effectively. Interestingly, these oligomers were clarified to possess a break point resembling a CMC ( critical micelle concentration ) and to be useful as new fluorinated oligosoaps, although hydrocarbon polysoap solutions are well known to not exhibit a CMC or a break point resembling a CMC ( 13 ) . This finding is considered to be a unique future in these fluoroalkylated oligomeric surfactants. In particular, each break point of perfluoro-oxaalkylated oligomers is likely to be observed in oligomer content ( ca. 0.5 g dm03 ) lower than that of perfluoropropylated oligomers. A particular future of our fluorinated oligomers in aqueous solutions cannot be explained in detail at the present time; however, these oligomers are suggested to form the intra- or intermolecular aggregates in aqueous solutions owing to exhibiting a clear break point resembling a CMC. Very recently, we have also found that fluoroalkyl end-capped allyl- and diallylammonium chloride oligomers are effective for reducing the surface tension of water to around 10 mN m01 , and a break point resembling a CMC is observed in their solutions ( 14 ) . In addition, we succeeded in preparing perfluoro-oxaalkylated 4-vinylpyridine oligomers in 34% [RF Å CF(CF3 )OC3F7 ] and 45% [RF Å
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LETTER TO THE EDITOR CF(CF3 )OCF2CF(CF3 )OC3F7 ] isolated yields by the reactions of the corresponding 4-vinylpyridinium chloride oligomers with aq. KOH as in the scheme
These fluoroalkylated 4-vinylpyridine oligomers were not soluble in water, but soluble in polar solvents such as methanol, ethanol, and N,N-dimethylformamide. Especially, these oligomers are expected to become useful precursors for preparing various fluoroalkylated 4-vinylpyridine oligomers quaternized by long alkyl groups. In this way, our new fluoroalkylated pyridinium oligomers were clarified to exhibit unique properties imparted by fluorine, although these compounds are fluoroalkyl end-capped hydrocarbon oligomers where fluoroalkyl segments were introduced into only two end-sites in one oligomer. Further studies of the synthesis and properties of cationic oligomers with fluoroalkanoyl peroxides are now actively in progress.
8. Sawada, H., Yamaguchi, K., Mitani, M., Nakajima, H., Nishida, M., and Moriya, Y., Polymer 35, 444 (1994). 9. Yoshida, M., Moriya, K., Sawada, H., and Kobayshi, M., Chem. Lett. 755 (1985). 10. Sawada, H., Yoshida, M., Hagii, H., Aoshima, K., and Kobayashi, M., Bull. Chem. Soc. Jpn. 59, 215 (1986). 11. This finding indicates that an interaction between the HOMO energy level of 4-VPC ( 014.017 eV; calculated value with MNDO-PM3 semiemprical MO method: Stewart, J. J. P., and Fujitsu Ltd. MOPAC 93, Tokyo, Japan) and LUMO (peroxide) weaker than that of 4-vinylpyridine ( 09.688 eV) or styrene ( 09.132 eV) causes a new interaction between HOMO (4-VPC) and SOMO of the fluoroalkyl radical (RFr) to derive not an electron transfer from 4-VPC to peroxide but an usual radical oligomerization. 12. Abe, M., Morikawa, K., Ogino, K., Sawada, H., Matsumoto, T., and Nakayama, M., Langmuir 8, 763 (1992). 13. Anton, P., Koberle, P., and Laschewsky, A., Makromol. Chem. 194, 1 (1993). 14. Sawada, H., Tanba, K.-I., Oue, M., Kawase, T., Hayakawa, Y., Mitani, M., Minoshima, Y., Nishida, M., and Moriya, Y., Polymer 36, 2103 (1995). HIDEO SAWADA * ,1 ATSUHITO WAKE * MASATOSHI OUE * TOKUZO KAWASE† YOSHIO HAYAK AWA‡ YOSHIHIRO MINOSHIMA§ MOTOHIRO MITANI§
REFERENCES 1. Dubin, P. B. (Ed.), ‘‘Microdomains in Polymer Solutions.’’ Plenum, New York, 1986. 2. Shinkai, S., Hirakawa, S., Shimomura, M., and Kunitake, T., J. Org. Chem. 46, 868 (1981). 3. (a) Wang, G.-J., and Engberts, J. B. F. N., Langmuir 10, 2583 (1994); (b) Yang, Y.-J., and Engberts, J. B. F. N., J. Org. Chem. 56, 4300 (1991). 4. (a) Sawada, H., J. Fluorine Chem. 61, 253 (1993); (b) Sawada, H., ‘‘Reviews on Heteroatom Chemistry’’ (S. Oae, Ed.), Vol. 8, p. 205. Myu, Tokyo, 1993; (c) Sawada, H., Matsumoto, T., and Nakayama, M., Yuki Gosei Kagaku Kyokaishi 50, 592 (1992). 5. Sawada, H., and Nakayama, M., J. Chem. Soc. Chem. Commun. 677 (1991). 6. Sawada, H., Gong, Y.-F., Minoshima, Y., Matsumoto, T., Nakayama, M., Kosugi, M., and Migita, T., J. Chem. Soc. Chem. Commun. 537 (1992). 7. Sawada, H., Tanba, K., Oue, M., Kawase, T., Mitani, M., Minoshima, Y., Nakajima, H., Nishida, M., and Moriya, Y., Polymer 35, 4028 (1994).
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m4860$$191
02-07-96 00:32:45
*Department of Chemistry Nara National College of Technology Yata, Yamatokoriyama, Nara, 639-11, Japan †Faculty of Science of Living Osaka City University Sugimoto, Sumiyoshi-ku, Osaka, 558, Japan ‡National Industrial Research Institute of Nagoya Kita-ku, Nagoya, 462, Japan §Tsukuba Research Laboratory NOF Corporation Tokodai, Tsukuba, Ibaraki, 300-26, Japan Received March 30, 1995; accepted September 22, 1995 1
To whom correspondence should be addressed.
coidas
AP: Colloid