10 2009 10 ACTA POL YMERICA SINICA No. 10 Oct., 2009 { ( + )2 22,52 [ 4 2( ( S)222 ) ] } 3 33 ( 100871) ( + )2 22,52 [4 2( ( S)222 ) ],. 30,Cotton,.,.,,,,.,,,,, [1 3 ].,, [3 7 ].,, [3 ].,,.,,.,.,. Okamoto [8 ]., mm 98 %., [3 ].,.,Percec,,, [9,10 ]., { ( + )22, 52 [ 4 2( ( S )222 ) ] } (MBPS) [11 ].,,., ( + )2 22,52 [4 2( ( S)222 ) ],. 1 111 (AR, ), (AR, ), N2 (NBS, 99 %, Aldrich), N, N, N, N, N 2 ( PMDETA, 99 %, Aldrich ), ( 99 %, 3 2009202216,2009203213 ; ( 20674001) ( 20325415) ( 20080440249) ; 33,E2mail :xhwan @pku. edu. cn 1050
10 : { ( + )2 22,52 [4 2( ( S)222 ) ] } 1051 Aldrich),22 (99 %,Aldrich), (AR,, ), (AR, ), (AR, ). (AR, ) CaH 2. (BPO, CP, ), ; 2, 2 (AIBN,CP). (AR, ) (AR, ). ( THF,AR, ) CaH 2,,. ( + )22,52 [ 4 2 ( ( S)222 ) ] [12 ]. 112 1 H2NMR Bruker ARX400 (400 MHz), CDCl 3, TMS. Finnigan2MAT ZAB2HS. Elemental Vario EL. ( GPC), Waters 515 Waters Styragel HT2 + HT3 + TH4,Waters 2410., 35, THF 110 mlπmin. Jasco Model P21030 25, 1 dm, THF. 2 Varian Cary2300, THF, 1 10-5 molπl. Jasco J2 810, 1 cm,thf, 1 10-5 molπl. 113 11311 1168 g (30 mmol) KOH 20 ml, 2158 g ( 30 mmol). 5113 g(30 mmol) AgNO 3 40 ml. KOH. 10 min,.,, 24 h 3170 g, 6412 %. 11312 ( + )22,52 [ 4 2( ( S )222 ) ] (BPBMA) 6125 g(15 mmol) ( + )22,52 [ 4 2( ( S)222 ) ], 2167 g(15 mmol) NBS 0112 g BPO 200 ml 3 h.,. 25 ml, (3167 g,19 mmol), 75 ml, 50,.,, ( 1Π1 Π ), Π, 4182 g, 6413 %. 1 H2NMR ( CDCl 3, 400 MHz, ) : 0195 0199 (,6H, ),1103 1105 (,6H, ),1124 1132 (,2H, ),1150 1165 (,2H, ),1185 1192 (, 2H, ), 1195 (, 3H, ), 3177 3180 (,2H, ),3184 3187 (, 2H, ),5118 (,2H, ),5156 5157 (, 1H, ), 6112 (, 1H, ),6194 7100 (,4H, ),7129 7136 (,3H, ),7154 7157 (,3H, ),7168 7169 ( d,1h, ). ( C 33 H 40 O 4 ), : C 79120, H 8100 ; : C 79120 ; H8102. ( mπe) :500 (, ),430, 360,274,181,69. [ ] 25 365 = + 5915 ( c = 012 gπdl,thf). 114 11411 60. 0124 g (0148 mmol), 41 L 10 mgπml AIBN, 1 ml. 3,. 60, 24 h., 20 ml THF, 200 ml., 0122 g, 91 %. 11412 (ATRP) 0150 g (110 mmol) 219 mg 98 L 40 mgπml 22 87 L 40 mgπml PMDETA 0150 g. 3,. 90,. THF, 200
1052 2009 300.,. 11413 250 ml 0115 g(013 mmol) 510 g KOH 20 ml THF 20 ml 40 ml, 72 h,,, THF, ( TLC), 5 % 24 h,. 60 48 h, 5 ml. 5 ml 0114 g, 30 min.., 01025 g, 83 %. 2 211 BPBMA 1.,,. NBS..,. Fig. 1 Synthesis of monomer BPBMA,. 2 1 H2NMR. 5, = 0195 1103 ; = 113 116 317 318 c f ; = 119., = 515 611 ; 2 = 210. = 511., k k, = 713 716 3, = 710 717 j l., = 515 611, e, = 018 112., = 414 510 ;,. 212 21211 ( [ ] 25 365 ) 5915, PBPBMA 25 ( 1), 35, PBPBMA. PBPBMA PMBPS Okamoto, PBPBMA. 3 2.,, Cotton, 302 270 nm Cotton,,
10 : { ( + )2 22,52 [4 2( ( S)222 ) ] } 1053 PBPBMA ( CH 2 OOC ), PMBPS.,. 21212 PBPBMA,, 1., 24,. Table 1 Free radical polymerization of BPBMA in different solvents a Solvent M n 10-4 M w 10-4 PDI Yield ( %) [ ] 25 365 ( ) Benzene 913 2811 3101 90 2410 THF 314 1114 3136 90 2417 CHCl 3 616 1916 2195 85 2519 Anisole 1112 2818 2156 91 2515 Anisole b 1619 3013 1179 91 2415 a Polymerization conditions : [ M ] = 015 molπl ; Temperature = 60 ; [AIBN]Π[M] = 1Π200 ;Time = 24 h ; b [AIBN]Π[M] = 3Π1000 2 BPBMA. 113 10 5, 27.. PMBPS.,.. Fig. 2 1 H2NMR spectra of BPBMA (A), PBPBMA (B), and the PMMA derived from PBPBMA (C). PMBPS 302 nm Cotton, PBPBMA. Table 2 Free radical polymerizations of BPBMA at different temperatures a Temperature ( ) M n 10-4 M w 10-4 PDI Yield ( %) [ ] 365 25 ( ) 50 1311 2411 1183 92 2710 60 1514 2615 1172 66 2318 70 1719 2614 1148 45 c 2712 80 2315 3114 1133 53 c 2715 90 1317 2218 1166 45 c 2717 90 b 1615 2410 1146 59 c 2810 a Polymerization conditions : [M] = 015 molπl ;I : AIBN for 50, 60, 70 and BPO for 80, 90, respectively ; [ I ]Π[ M ] = 1Π200 ; Solvent : anisole ;Time = 24 h ; b [ M ] = 1 molπl ; c Precipitates formed during polymerization Fig. 3 UV2Vis absorption and circular dichroism spectra of BPBMA and PBPBMA 21213 [13 ]. PBPBMA, ATRP, 3.,
1054 2009 25 (run 6),.,,. Run Table 3 ATRP of BPBMA in anisole at 90 M n 10-4 M w 10-4 PDI Yield ( %) [ ] 25 365 ( ) 1 0145 0151 1113 52 3316 2 0192 1103 1112 45 2712 3 1102 1114 1112 69 3110 4 1110 1123 1112 88 2816 5 1119 1133 1111 90 2817 6 1122 1142 1117 90 2415 7 1125 1140 1111 86 2717 8 1160 1176 1110 86 2619 9 1173 2102 1117 88 2610 10 1188 2106 1110 89 2811 213 PBPBMA, 1 5,. 2(C) 1 H2NMR., = 6 8 = 5, = 316,,., 2 mmπmrπrr = 10Π30Π60. mm 10 %,. PBPBMA. 3 BPBMA, ATRP PBPBMA. 30, - Cotton,,,., PBPBMA 25. PMBPS,PBPBMA. PBPBMA,,.. BPBMA,. REFERENCES 1 Green M M,Park J W,Sato T,Teramoto A,Lifson S,Selinger R L B,Selinger J V. Angew Chem Int Ed,1999,38 :3138 3154 2 Rowan A E,Nolte R J M. Angew Chem Int Ed,1998,37 :63 68 3 Nakano T,Okamoto Y. Chem Rev,2001,101 :4013 4038 4 Wang Yuechuan( ),Ding Mengxian( ),Xu Jingzhe ( ),Wang Fosong( ). Acta Polymerica Sinica ( ),1988, (4) :317 320 5 Chen Chuanfu( ),Liu Weihong( ),Chen Yongming( ),Ren Changyu( ),Xi Fu( ). Acta Polymerica Sinica ( ),1996, (1) :126 128 6 Lam J W Y,Tang B Z. Acc Chem Res,2005,38 :745 754 7 Lam J W Y,Tang B Z.J Polym Sci Part A :Polym Chem,2003,41 :2607 2629 8 Okamoto Y,Nishikawa M,Nakano T,Yashima E,Hatada K. Macromolecules,1995,28 :5135 5138 9 Kwon Y K,Chvalun S N,Blackwell J,Percec V,Heck J A. Macromolecules,1995,28 :1552 1558 10 Percec V,Ahn C H,Ungar G,Yeardley D J P,Mgller M,Sheiko S S. Nature,1998,391 :161 164 11 Yu Z,Wan X,Zhang H,Chen X,Zhou Q. Chem Commun,2003 :974 975 12 Yu Z,Tu H,Wan X,Chen X,Zhou Q F.J Polym Sci Part A :Polym Chem,2003,41 :1454 1464 13 Nakano T,Okamoto Y,Hatada K.J Am Chem Soc,1992,114 :1318 1329
10 : { ( + )2 22,52 [4 2( ( S)222 ) ] } 1055 SY NTHESIS AND CHARACTERIZATION OF OPTICALLY ACTIVE POLY{ ( + ) 22,52 BIS[4 2( ( S) 2(22METHYL BUTOXYPHENYL) ] BENZYL METHACRYLATE} CUI Jiaxi, CAO Hongqing, LIU Anhua, WAN Xinhua ( Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Department of Polymer Science & Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871) Abstract A chiral vinyl monomer, ( + )22, 52bis [ 4 2( ( S ) 2( 22methylbutoxyphenyl) ] benzyl methacrylate, was synthesized and polymerized via both conventional radical polymerization and atom transfer radical polymerization. The monomer showed a specific optical rotation [ ] 25 365 ( c = 012 gπdl) of 5915 in THF,while the corresponding polymer displayed its [ ] 25 365 value less than that of monomer for about 30. In the UV2Vis absorption regions of ester and p2terphenyl side2groups,the monomer exhibited very weak Cotton effects. In a sharp contrast,the polymer gave negative and positive Cotton effects centered at 302 and 270 nm, respectively. These results suggested the formation of a chiral secondary structure of polymer backbone,the optical rotation of which was opposite to that of monomer. For a vinyl polymer like poly{ ( + )22, 52bis [ 4 2( ( S ) 2( 22methylbutoxyphenyl) ] benzyl methacrylate} ( PBPBMA),the most possible chiral structure was helical conformation of main2chain with an excess helix sense. The reaction temperature and solvent were varied to study the effect of polymerization condition on the [ ] 365 25 value of the polymer. It was found that the [ ] 365 25 value of the polymer was independent on the polymerization conditions employed. The specific optical rotations of polymers decreased with increasing molecular weight at beginning and then leveled off, consistent with the speculation of helical conformation generation. The content of mm dyads of PBPBMA was only about 10 % as estimated with 1 H2NMR by converting the polymer to poly(methyl methacrylate) ( PMMA),which was comparable to that of PMMA obtained via conventional radical polymerization. This might account for the lower optical activity of PBPBMA compared to that of poly { ( + )22, 52bis [ 4 2( ( S )222 methylbutyloxy) phenyl ] styrene},an optically active helical vinyl polymer with similar structure. Keywords Specific optical rotation, Optically active helical polymer, Chirality, Radical polymerization, Atom transfer radical polymerization