Cyanoethynylethenes
FULL PAPER
1601, 1528, 1459, 1441, 1365, 1280, 1234, 1188, 1103, 981, 943, 813 cmꢁ1
;
(Z)- and (E)-2-{[4-(Dimethylamino)phenyl]ethynyl}-3-[(triisopropylsilyl)-
ethynyl]-5-(trimethylsilyl)pent-2-en-4-ynenitrile ((Z)-14 and (E)-14):
iPr2NH (58 mL, 0.41 mmol), [PdCl2(PPh3)2] (4.8 mg, 0.0069 mmol), and
CuI (2.0 mg, 0.010 mmol) were added to a degassed solution (Ar) of 41
UV/Vis (CHCl3): l (e)=296 (25600), 347 (4000), 524 nm (47300); UV/
Vis (CHCl3/hexane 1:1): l (e)=293 (25100), 326 (sh, 7300), 345 (sh,
3200), 508 nm (49000); UV/Vis (CHCl3/hexane 1:9): l (e)=287 (25500),
323 (sh, 7300), 339 (sh, 2700), 489 nm (55500); fluorescence (reference
rhodamine 6G; CHCl3/hexane 1:9): fF =0.012; fluorescence (reference
rhodamine 6G; CHCl3/hexane 1:1): fF =0.002; FT-MALDI-MS (DHB):
m/z: 364 [M]+, 387 [M+Na]+; elemental analysis calcd (%) for C24H20N4
(364.45): C 79.10, H 5.53, N 15.37; found: C 79.14, H 5.64, N 15.22.
(50 mg,
0.14 mmol)
and
N,N-dimethyl-4-ethynylaniline
(40 mg,
0.28 mmol) in benzene (5 mL). After stirring for 13 h, the solvent was
evaporated. Subsequent CC (CH2Cl2/hexane 1:1) resulted in (Z)-14
(27 mg, 42%) and (E)-14 (38 mg, 58%), both as red oils that solidify
upon standing. Each isomer contains ~15% of the other isomer, even
after multiple purifications.
Data for (Z)-14: M.p. 82–848C; 1H NMR (300 MHz, CDCl3): d=0.29 (s,
9H), 1.14 (m, 21H), 3.04 (s, 6H), 6.64 (d, J=9.0 Hz, 2H), 7.37 ppm (d,
J=9.0 Hz, 2H); 13C NMR (75 MHz, CDCl3): d=ꢁ0.40, 11.17, 18.54,
40.04, 83.80, 100.04, 101.58, 105.64, 106.15, 107.67, 108.52, 109.02, 111.58,
115.21, 120.69, 133.42, 151.04 ppm; IR (neat): n˜ =2944, 2864, 2186, 2138,
1600, 1533, 1458, 1441, 1374, 1340, 1266, 1250, 1194, 1124, 1071, 1010,
998, 947, 922, 885, 845, 807, 758, 742 cmꢁ1; UV/Vis (CHCl3): l (e)=290
(17900), 325 (15300), 471 nm (25600); FT-MALDI-MS (DHB): m/z: 473
[M+H]+, 495 [M+Na]+; elemental analysis calcd (%) for C29H40N2Si2
(472.82): C 73.67, H 8.53, N 5.92; found: C 73.63, H 8.60, N 5.71.
Data for (E)-14: M.p. 94–978C; 1H NMR (300 MHz, CDCl3): d=0.27 (s,
9H), 1.14 (m, 21H), 3.03 (s, 6H), 6.62 (d, J=9.0 Hz, 2H), 7.36 ppm (d,
J=9.0 Hz, 2H); 13C NMR (75 MHz, CDCl3): d=ꢁ0.39, 11.34, 18.71,
40.10, 83.60, 100.04, 101.80, 105.91, 106.92, 107.51, 107.69, 108.23, 111.41,
115.30, 120.43, 133.30, 150.84 ppm; IR (neat): n˜ =2939, 2863, 2185, 2139,
1602, 1532, 1461, 1444, 1367, 1341, 1264, 1251, 1232, 1194, 1122, 1064,
1011, 998, 944, 922, 884, 845, 809, 757, 742 cmꢁ1; UV/Vis (CHCl3): l (e)=
292 (20800), 322 (17500), 470 nm (26600); FT-MALDI-MS (DHB): m/z:
473 [M+H]+, 495 [M+Na]+; elemental analysis calcd (%) for
C29H40N2Si2 (472.82): C 73.67, H 8.53, N 5.92; found: C 73.54, H 8.44, N
5.72.
3,8-Bis{[4-(dimethylamino)phenyl]ethynyl}-2,9-dicyanodeca-2,8-diene-
4,6-diynedinitrile (20): MeOH/THF 1:1 (20 mL) was added to 15 (75 mg,
0.24 mmol). After stirring for 30 min at RT, CH2Cl2 (20 mL) and H2O
(20 mL) were added. The aqueous layer was extracted with CH2Cl2, and
the collected organic layers were washed twice with sat. NaCl solution.
After drying with MgSO4 and concentration to ~20 mL, Hay catalyst
(0.325 mL, 0.042 mmol) was slowly added. After stirring for 30 min, the
mixture was subjected to CC (CH2Cl2). Recrystallization from CH2Cl2/
hexane and subsequent CC (CH2Cl2) afforded 20 (10.8 mg, 19%) as a
1
black solid. M.p.>4108C; H NMR (300 MHz, CDCl3): d=3.12 (s, 12H),
6.67 (d, J=9.0 Hz, 4H), 7.55 ppm (d, J=9.0 Hz, 4H); 13C NMR
(75 MHz, CDCl3): d=40.17, 81.24, 85.17, 89.60, 90.41, 105.00, 111.78,
112.60, 112.65, 119.12, 130.99, 135.81, 152.74 ppm; IR (KBr): n˜ =3447,
2920, 2224, 2159, 2142, 1599, 1534, 1472, 1440, 1379, 1361, 1243, 1191,
1131, 1120, 976, 939, 816 cmꢁ1; UV/Vis (CHCl3): l (e)=311 (26300), 403
(16300), 600 nm (30700); FT-MALDI-MS (DHB): m/z: 511 [M+Na]+,
489 [M+H]+, 474 [M+HꢁMe]+; HR-FT-MALDI-MS: m/z calcd for
C32H20N6+: 488.1749; 488.1739 [M]+.
3,12-Bis{[4-(dimethylamino)phenyl]ethynyl}-2,13-dicyanotetradeca-2,12-
diene-4,6,8,10-tetraynedinitrile (21): THF/MeOH 1:1 (10 mL) was added
to 16 (15 mg, 0.044 mmol). After stirring for 30 min at RT, CH2Cl2
(20 mL) and H2O (20 mL) were added. The aqueous layer was extracted
with CH2Cl2, and the collected organic layers were washed twice with sat.
NaCl solution. After drying with MgSO4, the solvent was evaporated in
vacuo. The residue was redissolved in THF (5 mL) and Cu(OAc)2 was
added. The mixture was stirred for five days at RT. Subsequent CC
(CH2Cl2) afforded 21 (9.3 mg, 79%) as a black metallic solid. M.p.>
4108C, but partially polymerized; 1H NMR (300 MHz, CDCl3): d=3.10
(s, 12H), 6.67 (d, J=9.2 Hz, 4H), 7.52 ppm (d, J=9.2 Hz, 4H); 13C NMR
(75 MHz, CDCl3): d=40.09, 65.79, 72.09, 74.07, 87.13, 89.53, 90.83,
105.01, 111.84, 112.67, 112.74, 118.41, 131.07, 135.83, 152.83 ppm; IR
(neat): n˜ =2924, 2854, 2140, 1598, 1532, 1465, 1442, 1367, 1252, 1172,
1108, 1044, 997, 942, 817, 788 cmꢁ1; UV/Vis (CHCl3): l (e)=297 (36400),
317 (39600), 332 (34100), 358 (34600), 386 (30100), 419 (25300), 457
(21000), 608 nm (41800); FT-MALDI-MS (DCTB): m/z: 536 [M]+; HR-
FT-MALDI-MS: m/z calcd for C36H20N6+: 536.1749; found: 536.1749
[M]+.
2-Cyano-3-(6-[4-(dimethylamino)phenyl]-4-{[4-(dimethylamino)phenyl]-
ethynyl}-3-[(triisopropylsilyl)ethynyl]hex-3-ene-1,5-diynyl)but-2-enedini-
trile (22): CuOAc (6.8 mg, 0.055 mmol) was added to a degassed solution
of 42 in THF/CH3CN 6:1 (7 mL). The mixture was heated to 508C for
1 h and TCNE (64 mg, 0.050 mmol) subsequently added. After stirring
for 2 h 40 min, the mixture was filtered through a plug (CH2Cl2). CC
(CH2Cl2/hexane 2:1) yielded 22 (5.6 mg, 21%) as a green solid. M.p.>
4108C (decomp); 1H NMR (300 MHz, CDCl3): d=1.16 (s, 21H), 3.06 (s,
6H), 3.08 (s, 6H), 6.65 (d, J=9.0 Hz, 2H), 6.67 (d, J=9.0 Hz, 2H), 7.47
(d, J=9.0 Hz, 2H), 7.54 ppm (d, J=9.0 Hz, 2H); 13C NMR (75 MHz,
CDCl3): d=11.29, 18.72, 40.06, 40.08, 89.95, 90.95, 94.01, 94.16, 100.85,
103.11, 106.12, 107.43, 107.84, 110.26, 110.76, 110.82, 111.34, 111.50,
111.54, 111.67, 119.65, 119.80, 129.59, 134.49, 134.83, 151.51, 151.57 ppm;
IR (CCl4): n˜ =2959, 2926, 2861, 2153, 2127, 1602, 1524, 1445, 1364, 1243,
1188, 1152, 1102, 1022, 1000, 945 cmꢁ1; UV/Vis (CHCl3): l (e)=307
(24600), 372 (sh, 13000), 417 (21900), 484 (sh, 8100), 677 (27700),
734 nm (27600); FT-MALDI-MS (DHB): m/z: 620 [M+H]+; HR-FT-
MALDI-MS: m/z calcd for C40H41N5Si+: 619.3131; found: 619.3134 [M]+.
2-{[4-(Dimethylamino)phenyl]ethynyl}-5-(triisopropylsilyl)-3-[(triisopro-
pylsilyl)ethynyl]pent-2-en-4-ynenitrile (13): iPr2NH (98 mL, 0.70 mmol),
[PdCl2(PPh3)2] (8.2 mg, 0.012 mmol), and CuI (3.3 mg, 0.017 mmol) were
added to a degassed solution (Ar) of 40 (105 mg, 0.233 mmol) and N,N-
dimethyl-4-ethynylaniline (102 mg, 0.702 mmol) in benzene (7 mL). After
stirring for 16 h at RT, the solvent was evaporated. Subsequent CC
(CH2Cl2/hexane 1:1) resulted in 13 (123 mg, 94%) as a red oil that solidi-
fied upon standing. M.p. 908C; 1H NMR (300 MHz, CDCl3): d=1.14 (m,
42H), 3.03 (s, 6H), 6.63 (d, J=9.0 Hz, 2H), 7.36 ppm (d, J=9.0 Hz, 2H);
13C NMR (75 MHz, CDCl3): d=11.10, 11.14, 18.49, 18.55, 39.99, 83.52,
102.09, 102.26, 105.11, 105.80, 106.66, 107.51, 107.60, 111.46, 115.34,
120.77, 133.37, 150.95 ppm; IR (neat): n˜ =2943, 2864, 2190, 2140, 1605,
1532, 1459, 1444, 1368, 1343, 1259, 1232, 1194, 1125, 1074, 1013, 1000,
946, 920, 883, 810, 744 cmꢁ1; UV/Vis (CHCl3): l (e)=293 (22900), 324
(18700), 344 (sh, 14300), 470 nm (30100); UV/Vis (hexane): l (e)=284
(21200), 317 (16800), 324 (sh, 16500), 335 (sh, 13200), 435 (sh, 29100),
458 nm (34800); fluorescence (reference anthracene; hexane): fF =0.39;
FT-MALDI-MS (DHB): m/z: 557 [M+H]+, 579 [M+Na]+; HR-FT-
MALDI-MS: m/z calcd for C35H53N2Si2: 557.3747; found: 557.3717
[M+H]+; elemental analysis calcd (%) for C35H52N2Si2 (556.98): C 75.48,
H 9.41, N 5.03; found: C 75.04, H 9.42, N 4.95;
2-(1,6-Bis[(triisopropylsilyl)ethynyl]-9-[4-(dimethylamino)phenyl]-7-{[4-
(dimethylamino)phenyl]ethynyl}non-6-ene-2,4,8-triynylidene)malononi-
trile (23): THF/MeOH 1:1 (15 mL), 42 (8.8 mg, 0.017 mmol), and Cu-
(OAc)2 (16.6 mg, 0.0914 mmol) were added to 6 (9.3 mg, 0.026 mmol).
After stirring for 6 h at RT, the mixture was passed through a plug
(CH2Cl2). Subsequent GPC (CH2Cl2) yielded 23 (1.7 mg, 13%) as a
green solid. M.p.>4108C; 1H NMR (300 MHz, CDCl3): d=1.15 (m,
42H), 3.036 (s, 6H), 3.044 (s, 6H), 6.65 (pseudo t, J=9.0 Hz, 4H), 7.43
(d, J=9.0 Hz, 2H), 7.46 ppm (d, J=9.0 Hz, 2H); 13C NMR (75 MHz,
CDCl3): d=11.18, 11.48, 18.61, 18.83, 40.12, 40.15, 79.49, 80.23, 87.74,
88.05, 93.36, 93.58, 95.57, 99.17, 101.60, 102.33, 105.23, 106.09, 108.06,
108.10, 108.40, 111.39, 111.76, 111.93, 112.10, 115.52, 126.39, 132.89,
133.63, 133.82, 150.78, 150.92 ppm; IR (CCl4): n˜ =2944, 2926, 2866, 2163,
2140, 1605, 1524, 1463, 1446, 1356, 1262, 1230, 1187, 1168, 1119, 1076,
1018, 998, 948, 883 cmꢁ1; UV/Vis (CHCl3): l (e)=311 (35700), 416
(22400), 434 (sh, 22000), 474 (sh, 18500), 554 (18100), 649 nm (sh,
14100); FT-MALDI-MS (DCTB): m/z: 798 [M]+; HR-FT-MALDI-MS:
m/z calcd for C52H62N4Si2+: 798.4513; found: 798.4516 [M]+.
Chem. Eur. J. 2005, 11, 3325 – 3341
ꢃ 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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