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J 5 18.3, 9.3 Hz; ACH2CH(AC)CH2COOA), 2.48 (dd, 2H,
J 5 18.3, 4.4 Hz; ACH2CH(AC)CH2COOA), 2.01 (m, 2H), 1.81
(m, 2H), 1.52 (m, 4H); 13C NMR (100 MHz, CDCl3, d): 172.2,
114.5, 44.6, 37.5, 37.2, 35.6, 32.1, 26.5, 22.2; IR (neat):
m 5 2940 (m), 2866 (w), 1783 (s), 1426 (w), 1269 (m), 1229
(m), 1144 (m), 979 (m), 940 (m), 895 (w), 865 cm21 (w).
1H NMR (400 MHz, CDCl3, d): 6.10 (s, 1H; CH2@C), 5.56 (s,
1H; CH2@C), 4.15 (t, 2H, J 5 6.5 Hz; ACOOCH2A), 3.10 (m,
1H; ACH2CH(AC)CH2A), 3.01 (dd, 2H, J 5 18.2, 9.4 Hz;
ACH2CH(AC)CH2COOA), 2.56 (dd, 2H, J 5 18.3, 4.3 Hz;
ACH2CH(AC)CH2COOA), 2.01 (m, 2H), 1.71 (m, 2H), 1.47–
1.56 (m, 4H); 13C NMR (100 MHz, CDCl3, d): 172.3, 167.5,
136.4, 125.4, 114.6, 64.2, 37.4, 37.2, 35.6, 28.4, 25.7, 22.5,
18.3; IR (neat): m 5 2949 (w), 1785 (s), 1708 (s), 1634 (m),
1454 (w), 1427 (w), 1322 (m), 1297 (m), 1243 (m), 1161
(s), 1060 (w), 983 (m), 935 (m), 893 (w), 867 (w), 816 (m),
786 cm21 (w). HRMS (m/z): calcd for C15H21O6, 297.1338;
found, 297.1341 [M 1 H]1.
HRMS (m/z): calcd for
247.0733 [M 1 H]1.
C11H16O4Cl, 247.0737; found,
Synthesis of Methacrylates 1b–1d
A typical procedure: Bislactone 3d (160 mg, 649 lmol),
sodium iodide (20 mg, 133 lmol), and sodium methacrylate
(168 mg, 1.55 mmol) were dissolved in dry DMF (1.6 mL)
and heated at 80 8C under N2 for 15 h. The mixture was con-
centrated under reduced pressure and the resulting residue
was dissolved in AcOEt (30 mL). The solution was washed
with saturated aqueous solution of ammonium chloride
(20 mL), dried over sodium sulfate, filtered, and evaporated
under reduced pressure. The crude product was purified by
silica gel column chromatography (eluent 5 AcOEt 1 hexane
3/1) to give 1d (103 mg, 54%).
Synthesis of Bislactone 5
To a solution of BPA (2.92 g, 16.2 mmol) in CHCl3 (15 mL),
DCC (1.67 g, 8.09 mmol) was added at RT, and the mixture
was stirred for 3 h. The mixture was filtered by washing the
precipitate with dichloromethane (10 mL), and the filtrate
was concentrated under reduced pressure. The resulting oil
was dissolved with toluene (20 mL), and the solution was fil-
tered and concentrated under reduced pressure to obtain
anhydride 4 (2.75 g).
Methacrylates 1b and 1c were synthesized from bislactones
3b and 3c, respectively, and isolated in a similar manner.
Anhydride 4 was dissolved in 1,4-dioxane (15 mL), and to
the resulting solution, 4-dimethylaminopyridine (DMAP)
(16 mg, 131 lmol) and PTA (476 mg, 2.70 mmol) were
added. The mixture was heated with refluxing for 3 h at
120 8C. After cooling to RT, the solution was concentrated
under reduced pressure. The residue was dissolved with
chloroform (30 mL), washed with saturated aqueous solution
of sodium bicarbonate (20 mL, twice), 1 M of hydrochloric
acid (20 mL), and brine (20 mL), dried over sodium sulfate,
and filtered. The filtrate was concentrated under reduced
pressure, and the residue was purified by silica gel column
(eluent 5 AcOEt 1 hexane 1/1) to afford 5 (374 mg, 17%) as
a viscous oil.
Bislactone 1b
It is colorless oil.
1H NMR (400 MHz, CDCl3, d): 6.10 (s, 1H; CH2@C), 5.59 (s,
1H; CH2@C), 4.23 (t, 2H, J 5 6.2 Hz; ACOOCH2A), 3.10 (m,
1H; ACH2CH(AC)CH22), 3.02 (dd, 2H, J 5 18.4, 9.3 Hz;
ACH2CH(AC)CH2COOA), 2.57 (dd, 2H, J 5 18.3, 4.2 Hz;
ACH2CH(AC)CH2COOA), 2.09 (m, 2H), 1.95 (m, 5H;
CH32C@CA, and ACOOACH2ACH2A); 13C NMR (100 MHz,
CDCl3, d): 172.0, 167.3, 136.1, 125.8, 114.1, 63.5, 37.7, 35.5,
34.2, 22.5, 18.3; IR (neat): m 5 2958 (w), 2927 (w), 2853
(w), 1784 (s), 1709 (s), 1635 (m), 1451 (w), 1425 (w), 1379
(m), 1321 (m), 1297 (w), 1160 (s), 1139 (s), 972 (s), 939
(s), 896 (m), 855 (m), 855 cm21 (w). HRMS (m/z): calcd for
1H NMR (400 MHz, CDCl3, d): 7.33 (m, 5H; ArH), 4.46 (s, 2H;
ArACH22OA), 3.68 (t, 2H, J 5 5.7 Hz; BnOACH2A), 3.44 (m,
1H; ACH2ACH(C) ACH22), 2.95 (dd, 2H, J 5 18.6, 10.0 Hz;
ACH2CH(AC)CH2COOA), 2.44 (dd, 2H, J 5 18.7, 4.5 Hz;
C
13H17O6, 269.1025; found, 269.1027 [M1H]1.
ACH2CH(AC)CH2COOA),
2.35
(t,
2H,
J 5 5.7
Hz;
Bislactone 1c
BnOCH2CH2A); 13C NMR (100 MHz, CDCl3, d): 172.8, 137.2,
128.6, 128.1, 127.9, 114.0, 73.6, 64.9, 37.8, 36.6, 35.6; IR
(neat): m 5 2933 (w), 2875 (w), 1791 (s), 1496 (w), 1453
(w), 1423 (w), 1367 (w), 1306 (w), 1261 (w), 1214 (m),
1137 (m), 1016 (w), 978 (m), 944 (m), 892 (w), 865 (m),
742 cm21 (w). HRMS (m/z): calcd for C15H16O5, 276.0998;
found, 276.0998 [M]1.
It is pale yellow oil.
1H NMR (400 MHz, CDCl3, d): 6.10 (s, 1H; CH2@C), 5.57 (s,
1H; CH2@C), 4.18 (t, 2H, J 5 6.3 Hz; ACOOCH2A), 3.57 (t,
2H, J 5 6.4 Hz; ClCH2A), 3.11 (m, 1H; ACH2CH(AC)CH2A),
3.00 (dd, 2H, J 5 18.2, 9.4 Hz; ACH2CH(AC)CH2COOA), 2.56
(dd, 2H, J 5 18.3, 4.4 Hz; ACH2CH(AC)CH2COOA), 2.04 (m,
2H), 1.94 (s, 3H; CH32C@CA), 1.76 (m, 2H), 1.63 (m, 2H);
13C NMR (100 MHz, CDCl3, d): 172.2, 167.4, 136.2, 125.6,
114.4, 63.8, 37.5, 36.8, 35.5, 28.2, 19.5, 18.3; IR (neat):
m 5 2957 (m), 1790 (s), 1713 (m), 1635(w), 1428 (w), 1322
(w), 1298 (w), 1261 (w), 1167 (m), 982 (m), 944 (m),
864 cm21 (w). HRMS (m/z): calcd for C14H18O6, 282.1103;
found, 282.1105 [M]1.
Synthesis of Methacrylate 1a
To a mixture of bislactone 5 (184 mg, 835 lmol) and metha-
cryloyl chloride (86 lL, 837 lmol), a 1-M solution of SnCl4
in dichloromethane (84 lL, 84 mmol) was added and stirred
for 1 h at 0 8C, then warmed to RT, and then stirred for addi-
tional 3 h. To the reaction mixture, saturated aqueous solu-
tion of ammonium chloride (10 mL) was added, and the
mixture was extracted with dichloromethane (20 mL). The
organic layer was dried over sodium sulfate, filtered, and
Bislactone 1d
It is colorless oil.
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JOURNAL OF POLYMER SCIENCE, PART A: POLYMER CHEMISTRY 2015, 53, 2462–2468