Pyrrole Oligomers
368±373
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raphy (10 g silica gel, eluent 1) afforded 5b (85.0 mg, 165 mmol, 33%) as a
oil. tR 0.48 (eluent 1); IR (KBr): nÄ 2980, 2930, 2862 (C H), 1732 (C O),
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pale yellow oil. tR 0.48 (eluent 1); IR (KBr): nÄ 2978, 2932 (C H), 1734
1600, 1524 (C C), 962 cm (C H, (E)-alkene); UV (CH3CN): lmax (log
e) 251.0 nm (4.202), 313.0 (4.345), 341.0 (4.284); 1H NMR (200 MHz,
C6D6): d 1.32 (s, 18H, C(CH3)3), 1.85 (s, 6H, 4''-CH3), 2.07 (s, 6H, 3''-
CH3), 7.09 (dd, J 6.0, 3.5 Hz, 2H, 4-H, 5-H), 7.20 (s, 2H, 5''-H), 7.27 (d, J
16.5 Hz, 2H, 1'-H), 7.82 (dd, J 6.0, 3.5 Hz, 2H, 3-H, 6-H), 7.95 (d, J
16.5 Hz, 2H, 2'-H); 13C NMR (50.3 MHz, CDCl3): d 10.36, 11.46 (3''-CH3,
4''-CH3), 28.09 (C(CH3)3), 82.96 (C(CH3)3), 118.3 (C-5''), 122.1 (C-3''), 122.3
(C-2'), 122.5 (C-4''), 125.9, 127.1, 127.2 (C-3, C-4, C-5, C-6, C-1'), 129.7 (C-
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(C O), 1626, 1594, 1578, 1520 (C C), 960 cm (C H, (E)-alkene); UV
(CH3CN): lmax (log e) 242.5 (4.314), 327.5 nm (4.527); 1H NMR
(300 MHz, [D6]DMSO): d 1.53 (s, 18H, C(CH3)3), 1.96 (s, 6H, 4-CH3),
2.10 (s, 6H, 3-CH3), 6.64 (d, J 16.5 Hz, 2H, 1'-H), 7.07 (s, 2H, 5''-H), 7.31 ±
7.42 (m, 3H, 4-H, 5-H, 6-H), 7.53 (d, J 16.5 Hz, 2H, 2'-H), 7.61 (brs, 1H,
2-H); 13C NMR (50.3 MHz, CDCl3): d 10.38, 11.38 (3-CH3, 4-CH3), 28.11
(C(CH3)3), 82.97 (C(CH3)3), 118.4 (C-5''), 120.7 (C-2'), 122.2, 122.7 (C-3'',
C-4''), 124.3 (C-2), 124.8 (C-4, C-6), 128.8 (C-5), 129.4 (C-2''), 129.7 (C-1'),
2''), 135.9 (C-1, C-2), 149.4 (C O); MS (70 eV): m/z (%): 516 (41) [M] , 416
138.2 (C-1, C-3), 149.5 (C O); MS (70 eV): m/z (%): 516 (23) [M] , 416
(14) [MꢀCO2C4H8] , 315 (46) [M ꢀ CO2C4H8 ꢀ CO2C4H9] , 123 (40)
(16) [M ꢀ CO2C4H8] , 316 (100) [M ꢀ 2 Â CO2C4H8] , 57 (41) [C4H9] ;
[C8H13N] , 57 (100) [C4H9] ; C32H40N2O4 (516.7): HMRS calcd 516.2988;
found 516.2988.
C32H40N2O4 (516.7): HMRS calcd 516.2988; found 516.2988.
(E,E)-1,4-Bis-[2'-(1''-tert-butoxycarbonyl-[1''H]-pyrrol-2''-yl)-vinyl]-ben-
zene (6a): According to general procedure IIa the vinylpyrrole 3a (483 mg,
2.50 mmol, 1.3 equiv) was reacted with 1,4-diiodobenzene (4b, 330 mg,
1.00 mmol, 1.0 equiv) for 20 h at 708C. Column chromatography (40 g silica
gel, eluent 2) afforded 6a (170 mg, 369 mmol, 37%) as yellow crystals. M.p.
(E,E)-1,4-Bis-[2'-(1''-tert-butoxycarbonyl-3'',4''-dimethyl-5''-ethoxycarbon-
yl-[1H]-pyrrol-2''-yl)-vinyl]-benzene (10b): According to general proce-
dure IIb the iodopyrrole 8 (708 mg, 1.80 mmol, 1.5 equiv) was treated with
1,4-divinylbenzene (9, 78.4 mg, 600 mmol, 1.0 equiv) for 2 h at 758C.
Column chromatography (10 g silica gel, eluent 5) afforded 10b (137 mg,
207 mmol, 35%) as yellow crystals. M.p. 1708C; tR 0.47 (eluent 3); IR
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>1808C (dec); tR 0.40 (eluent 2); IR (KBr): nÄ 3004, 2980, 2932 (C H),
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1738 (C O), 1620, 1652, 1510 (C C), 958 cm (C H, (E)-alkene); UV
(CH3CN): lmax (log e) 197.0 (4.532), 244.5 (4.138), 377.0 nm (4.685);
1H NMR (300 MHz, CDCl3): d 1.63 (s, 18H, C(CH3)3), 6.19 (t, J 3.5 Hz,
2H, 4''-H), 6.56 (m, 2H, 3''-H), 6.87 (d, J 16.5 Hz, 2H, 1'-H), 7.28 (dd, J
3.5, 1.5 Hz, 2H, 5'-H), 7.44 (s, 4H, Ph-H), 7.75 (d, J 16.5 Hz, 2H, 2'-H);
13C NMR (50.3 MHz, CDCl3): d 28.0 (C(CH3)3), 83.8 (C(CH3)3), 110.7 (C-
4''), 111.1 (C-3''), 119.3 (C-2'), 122.2 (C-5''), 126.6 (C-2, C-3, C-5, C-6), 127.8
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(KBr): nÄ 2980, 2936, 2906 (C H), 1746 (carbamate-C O), 1692 (ester-
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C O), 1564, 1512 (C C), 960 cm (C H, (E)-alkene); UV (CH3CN): lmax
(log e) 191.0 (4.481), 227.0 (4.144), 377.5 (4.688), 379.5 nm (4.688);
1H NMR (200 MHz, CDCl3): d 1.37 (t, J 7.0 Hz, 6H, CO2CH2CH3), 1.58
(s, 18H, C(CH3)3), 2.16 (s, 6H, 4-CH3), 2.23 (s, 6H, 3-CH3), 4.33 (q, J
7.0 Hz, 4H, CO2CH2CH3), 6.76 (d, J 17.0 Hz, 2H, 1'-H), 7.31 (d, J
17.0 Hz, 2H, 2'-H), 7.45 (s, 4H, Ph-H); 13C NMR (50.3 MHz, CDCl3): d
10.4 (3''-CH3), 11.0 (4''-CH3), 14.4 (CO2CH2CH3), 27.7 (C(CH3)3), 60.5
(CO2CH2CH3), 84.5 (C(CH3)3), 117.9 (C-2'), 120.4, 121.7 (C-3'', C-4''), 126.7
(C-2, C-3, C-5, C-6), 130.2 (C-5''), 132.3 (C-1'), 132.8 (C-2''); 136.8 (C-1,
(C-1'), 134.4 (C-2''), 136.7 (C-1, C-4), 149.4 (C O); MS (70 eV): m/z (%):
460 (30) [M] , 404 (8) [M ꢀ C4H8] , 360 (12) [M ꢀ CO2C4H8] , 348 (100)
[M ꢀ 2 Â C4H8] , 304 (37) [M ꢀ CO2C4H8 ꢀ C4H8] , 259 (31) [M ꢀ
CO2C4H8 ꢀ CO2C4H9] , 57 (13) [C4H9] ; C28H32N2O4 (460.6): calcd C
C-6), 149.9 (carbamate-C O), 161.7 (ester-C O); MS (70 eV): m/z (%):
73.02, H 7.00; found C 73.08, H 7.04.
661 (2) [M] , 561 (7) [M ꢀ CO2C4H8] , 460 (100) [M ꢀ CO2C4H8 ꢀ
CO2C4H9] , 413 (12) [M ꢀ 2 Â CO2C4H9 ꢀ OC2H5] ; C38H48N2O8 (660.8):
(E,E)-1,4-Bis-[2'-(1''-tert-butoxycarbonyl-3'',4''-dimethyl-[1''H]-pyrrol-2''-
yl)-vinyl]-benzene (6b): According to general procedure IIc vinylpyrrole
3b (277 mg, 1.25 mmol, 1.3 equiv) was treated with 1,4-diiodobenzene (4b,
165 mg, 500 mmol, 1.0 equiv) for 4 h at 908C. Column chromatography
(eluent 2) afforded 6b (72.3 mg, 139 mmol, 28%) as yellow crystals. M.p.
calcd C 69.07, H 7.32; found C 68.90, H 7.25.
2-[(E)-2'-(4''-Formylphenyl)-vinyl]-[1H]-1-N-tert-butyloxycarbonyl-pyrrol
(12): According to general procedure IIa the vinylpyrrole 3a (212 mg,
1.10 mmol, 1.1 equiv) was treated with 4-iodobenzaldehyde (11, 232 mg,
1.00 mmol, 1.0 equiv) for 4 h at 908C. Column chromatography (20 g silica
gel, eluent 2) afforded 12 (140 mg, 471 mmol, 47%) as a yellow oil. tR 0.34
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>2008C (dec); tr 0.49 (eluent 1); IR (KBr): nÄ 3002, 2974, 2926 (C H),
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1720 (C O), 1628, 1566, 1506 (C C), 960 cm (C H, (E)-alkene); UV
(CH2Cl2): lmax (log e) 251.0 (4.122), 372.5 nm (4.536); 1H NMR
(200 MHz, CDCl3): d 1.58 (s, 18H, C(CH3)3), 2.00 (s, 6H, 4''-CH3), 2.15
(s, 6H, 3''-CH3), 6.59 (d, J 16.5 Hz, 2H, 1'-H), 7.04 (s, 2H, 5'-H), 7.44 (s,
4H, Ph-H), 7.56 (d, J 16.5 Hz, 2H, 2'-H); 13C NMR (50.3 MHz, CDCl3):
d 10.37, 11.36 (3''-CH3, 4''-CH3), 28.16 (C(CH3)3), 83.00 (C(CH3)3), 118.4
(C-5''), 120.1 (C-2'), 122.2, 122.7 (C-3, C-4), 126.3 (C-2, C-3, C-5, C-6), 129.4
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(eluent 2); IR (neat): nÄ 2980, 2934, 2842, 2732 (C H), 1742 (carbamate-
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C O), 1696 (aldehyde-C O), 1598, 1564 (C C), 962 cm (C H, (E)-
alkene); UV (CH3CN): lmax (log e) 194.0 (4.472), 251.5 (4.042), 360.5 nm
1
(4.346); H NMR (200 MHz, C6D6): d 1.29 (s, 9H, C(CH3)3), 6.10 (t, J
3.5 Hz, 1H, 4-H), 6.52 (m, 1H, 3-H), 6.77 (d, J 16.5 Hz, 1H, 2'-H), 7.26 (d,
J 8.5 Hz, 2H, 2''-H, 6''-H), 7.32 (dd, J 3.5, 1.5 Hz, 1H, 5-H), 7.52 (d, J
8.5 Hz, 2H, 3''-H, 5''-H), 8.17 (d, J 16.5 Hz, 1H, 1'-H), 9.66 (s, 1H, CHO);
13C NMR (50.3 MHz, CDCl3): d 27.84 (C(CH3)3), 83.97 (C(CH3)3), 111.2,
111.8 (C-3, C-4), 122.8 (C-1'), 122.9 (C-5), 126.2 (C-2'), 126.4 (C-2'', C-6''),
(C-1'), 129.4 (C-2''), 136.9 (C-1, C-4), 149.5 (C O); MS (70 eV): m/z (%):
516 (72) [M] , 404 (99) [M ꢀ 2 Â C4H8] , 315 (100) [M ꢀ CO2C4H8 ꢀ
CO2C4H9] , 57 (13) [C4H9] ; C32H40N2O4 (516.7): HMRS calcd 516.2988;
found 516.2988.
129.9 (C-3'', C-5''), 133.5, 134.8 (C-2, C-4''), 143.6 (C-1''), 149.1 (carbamate-
(E,E)-1,2-Bis-[2'-(1''-tert-butoxycarbonyl-[1''H]-pyrrol-2''-yl)-vinyl]-ben-
zene (7a): According to general procedure IId the vinylpyrrole 3a (483 mg,
2.50 mmol, 1.3 equiv) was treated with 1,2-diiodobenzene (4c, 330 mg,
1.00 mmol, 1.0 equiv) for 20 h at 908C. Column chromatography (eluent 2)
afforded 7a (216 mg, 469 mmol, 47%) as a yellow oil. tR 0.39 (eluent 2);
C O), 191.2 (aldehyde-C O); MS (70 eV): m/z (%): 297 (24) [M] , 241
(100) [M ꢀ C4H8] , 197 (61) [M ꢀ CO2C4H8] , 168 (33) [M ꢀ CO2C4H8 ꢀ
CHO] , 57 (78) [C4H9] ; C18H19NO3 (297.4): calcd C 72.71, H 6.44; found C
72.84, H 6.55.
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IR (neat): nÄ 2978, 2932, 2866 (C H), 1742 (C O), 1616, 1548 (C C),
2-[(E)-2'-(4''-Vinylphenyl)-vinyl]-[1H]-1-N-tert-butyloxycarbonyl-pyrrol
(13): According to general procedure I aldehyde 12 (2.12 g, 7.13 mmol) was
subjected to a Wittig reaction. Column chromatography (100 g silica gel,
eluent 4) afforded compound 13 (1.51 g, 5.11 mmol, 72%) as a pale yellow
958 cmꢀ1 (C H, (E)-alkene); UV (CH3CN): lmax (log e) 311.0 nm (3.981);
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1H NMR (200 MHz, C6D6): d 1.29 (s, 18H, C(CH3)3), 6.08 (t, J 3.5 Hz,
2H, 4''-H), 6.50 (m, 2H, 3''-H), 7.05 (dd, J 6.0, 3.5 Hz, 2H, 4-H, 5-H), 7.34
(dd, J 3.5, 1.5 Hz, 2H, 5''-H), 7.48 (d, J 16.0 Hz, 2H, 1'-H), 7.65 (dd, J
6.0, 3.5 Hz, 2H, 3-H, 6-H), 8.03 (d, J 16.0 Hz, 2H, 2'-H); 13C NMR
(50.3 MHz, CDCl3): d 28.02 (C(CH3)3), 83.84 (C(CH3)3), 110.9, 111.0
(C-3'', C-4''), 121.8 (C-2'), 122.2 (C-5''), 125.9, 126.4, 127.4 (C-3, C-4, C-5,
solid. M.p. 778C; tR 0.57 (eluent 2); IR (KBr): nÄ 3040, 3002, 2976, 2932
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(C H), 1744 (C O), 1622, 1602, 1550, 1508 (C C), 966 cm (C H, (E)-
alkene); UV (CH3CN): lmax (log e) 197.0 (4.502), 240.5 (4.019), 344.5 nm
1
(4.494); H NMR (300 MHz, CDCl3): d 1.62 (s, 9H, C(CH3)3), 5.23 (dd,
C-6, C-1'), 134.6, 135.8 (C-1, C-2, C-2''), 149.4 (C O); MS (70 eV): m/z (%):
J 11.0, 1.0 Hz, 1H, trans CH2), 5.74 (dd, J 18.0, 1.0 Hz, 1H, cis CH2),
6.19 (t, J 3.5 Hz, 1H, 4-H), 6.56 (m, 1H, 3-H), 6.70 (dd, J 18.0, 11.0 Hz,
1H, CH CH2), 6.87 (d, J 16.5 Hz, 1H, 2'-H), 7.28 (dd, J 3.5, 1.5 Hz,
1H, 5-H), 7.37, 7.43 (AA'BB'-system, J 8.0 Hz, 4H, Ph-H), 7.76 (d, J
16.5 Hz, 1H, 1'-H); 13C NMR (50.3 MHz, CDCl3): d 28.0 (C(CH3)3), 83.8
460 (44) [M] , 404 (11) [M ꢀ C4H8] , 348 (36) [M ꢀ 2 Â C4H8] , 304 (17)
[M ꢀ CO2C4H8 ꢀ C4H8] , 259 (26) [M ꢀ CO2C4H8 ꢀ CO2C4H9] , 193 (27),
180 (32), 57 (13) [C4H9]; C28H32N2O4 (460.6): calcd C 73.02, H 7.00; found
C 73.00, H 7.00.
(E,E)-1,2-Bis-[2'-(1''-tert-butoxycarbonyl-3'',4''-dimethyl-[1''H]-pyrrol-2''-
yl)-vinyl]-benzene (7b): According to general procedure IIc vinyl pyrrole
3b (553 mg, 2.50 mmol, 1.3 equiv) was treated with 1,2-diiodobenzene (4c,
330 mg, 1.00 mmol, 1.0 equiv) for 5h at 908C. Column chromatography
(10 g silica gel, eluent 1) afforded 7b (52.4 mg, 101 mmol, 10%) as a yellow
(C(CH3)3), 110.7 (C-4), 111.1 (C-3), 113.4 (CH CH2), 119.7 (C-1'), 122.3
(C-5), 126.4 (C-2'', C-3'', C-5'', C-6''), 127.7 (C-2'), 134.3 (C-2), 136.4
(CH CH2), 137.2 (C-1'', C-4''), 149.4 (C O); MS (70 eV): m/z (%): 295 (16)
[M] , 239 (100) [M ꢀ C4H8] , 195 (42) [M ꢀ CO2C4H8] , 57 (32) [C4H9] ;
C19H21NO2 (295.4): HMRS calcd 295.1572; found 295.1572.
Chem. Eur. J. 2001, 7, No. 2
ꢀ WILEY-VCH Verlag GmbH, D-69451 Weinheim, 2001
0947-6539/01/0702-0371 $ 17.50+.50/0
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