1094
Russ.Chem.Bull., Int.Ed., Vol. 60, No. 6, June, 2011
Makarova et al.
3ꢀ(5ꢀMethoxyꢀ1,2ꢀdimethylꢀ1Hꢀindolꢀ3ꢀyl)ꢀ4ꢀ[(E)ꢀoctꢀ1ꢀ
enyl]furanꢀ2,5ꢀdione (5c) was synthesized by analogy with comꢀ
pound 5a from dimethylindole 1 and (E)ꢀdecꢀ3ꢀenoic acid. The
yield was 0.3 g (26.4%), red crystals, m.p. 112—114 °C. IR,
ν/cm–1: 1750, 1820 (C=O). 1H NMR, δ: 0.86 (br.t, 3 H, Me,
J = 7.0 Hz); 1.16—1.35 (m, 6 H, CH2); 1.36—1.48 (m, 2 H, CH2);
2.20 (q, 2 H, CH2, J = 7.0 Hz); 2.42, 3.73, and 3.79 (all s,
3 H each, NMe, C(2)Me, OMe); 6.21 (br.d, 1 H, CH, J = 16.0 Hz);
6.78 (d, 1 H, HAr, J = 2.3 Hz); 7.16—7.30 (m, 2 H, HAr).
Found (%): C, 72.86; H, 7.01; N, 3.54. C23H27NO4. Calculatꢀ
ed (%): C, 73.00; H, 7.15; N, 3.68.
3ꢀ(1ꢀBenzylꢀ5ꢀmethoxyꢀ2ꢀmethylꢀ1Hꢀindolꢀ3ꢀyl)ꢀ4ꢀ[(E)ꢀ
propꢀ1ꢀenyl]furanꢀ2,5ꢀdione (5d) was synthesized by analogy with
compound 5a from 1ꢀbenzylindole 2 and (E)ꢀpentꢀ3ꢀenoic acid.
The yield was 0.29 g (31%), red crystals, m.p. 150—152 °C. IR,
ν/cm–1: 1750, 1820 (C=O). 1H NMR, δ: 1.95 (dd, 3 H, Me,
J1 = 7.0 Hz, J2 = 1.6 Hz); 2.38 (s, 3 H, Me); 3.80 (s, 3 H, OMe);
5.36 (s, 2 H, CH2); 6.24—6.32 (dq, 1 H, CH, J1 = 16.0 Hz,
J2 = 1.6 Hz); 6.82—6.95 (m, 2 H, HAr); 7.00—7.12 (m, 2 H, HAr);
7.14—7.22 (m, 2 H, HAr); 7.24—7.38 (m, 3 H, HAr). Found (%):
C, 74.36; H, 5.41; N, 3.60. C24H21NO4. Calculated (%): C, 74.40;
H, 5.46; N, 3.62.
Experimental
The electronic absorption spectra were measured on a Cary
100 spectrophotometer (Varian); the optical path length was
1 cm. The fluorescence measurements were carried out on a Cary
Eclipse spectrofluorimeter (Varian). The fluorescence quantum
yields were determined by the Parker—Rees method18 with the
use of a solution of 3ꢀmethoxybenzanthrone in toluene as the
reference luminophore.19 The solutions were irradiated in
a quartz cell (l = 1 cm) with a DRShꢀ250 mercury lamp equipped
with a kit of interference light filters to select lines of the mercuꢀ
ry spectrum. The kinetic curves for the photocoloration of soluꢀ
tions of dihetarylethenes were measured directly during irradiaꢀ
tion on a Cary 50 spectrophotometer (Varian) equipped with
a temperatureꢀcontrolled cell holder. A xenon lamp equipped
with a monochromator to produce narrow spectral lines (Newꢀ
port) was used as the radiation source. The optical radiation
intensity was determined with a Newport 2935 optical power
meter. The optical radiation intensity at the wavelengths used
(436 and 546 nm) was 2.94•1015 and 6.30•1015 photon s–1, reꢀ
spectively. To determine the photocolorability (Φ •ε B), the
AB max
slope of the tangent line at the initial instant was calculated from
the kinetic curves for the photocoloration.
3ꢀ(1ꢀBenzylꢀ5ꢀmethoxyꢀ2ꢀmethylꢀ1Hꢀindolꢀ3ꢀyl)ꢀ4ꢀ[(E)ꢀ
butꢀ1ꢀenyl]furanꢀ2,5ꢀdione (5e) was synthesized by analogy with
compound 5a from 1ꢀbenzylindole 2 and (E)ꢀhexꢀ3ꢀenoic acid.
The yield was 0.29 g (30%), red crystals, m.p. 148—149 °C. IR,
ν/cm–1: 1750, 1820 (C=O). 1H NMR, δ: 1.05 (t, 3 H, Me,
J = 7.3 Hz); 2.27 (q.d, 2 H, CH2, J1 = 7.2 Hz, J2 = 1.5 Hz); 2.37
(s, 3 H, Me); 3.80 (s, 3 H, OMe); 5.36 (s, 2 H, CH2); 6.25 (dt, 1 H,
CH, J1 = 16.0 Hz, J2 = 1.5 Hz); 6.82—6.95 (m, 2 H, CH, HAr);
7.00—7.12 (m, 2 H, HAr); 7.14—7.22 (m, 2 H, HAr); 7.28—7.40
(m, 3 H, HAr). Found (%): C, 74.77; H, 5.69; N, 3.44. C25H23NO4.
Calculated (%): C, 74.80; H, 5.77; N, 3.49.
The IR spectra in Nujol mulls were recorded on a Varian
Excalibur 3100 FTꢀIR instrument. The 1H NMR spectra
were measured in CDCl3 on a Varian Unityꢀ300 instrument
(300 MHz) with hexamethyldisiloxane as the external standard.
5ꢀMethoxyꢀ1,2ꢀdimethylindole (1) was synthesized accordꢀ
ing to a known procedure,8 m.p. 67—68 °C.
1ꢀBenzylꢀ5ꢀmethoxyꢀ2ꢀmethylindole (2) was synthesized acꢀ
cording to a procedure published earlier,9 m.p. 114—115 °C.
3ꢀ(5ꢀMethoxyꢀ1,2ꢀdimethylꢀ1Hꢀindolꢀ3ꢀyl)ꢀ4ꢀ[(E)ꢀpropꢀ1ꢀ
enyl]furanꢀ2,5ꢀdione (5a). Oxalyl chloride (0.26 mL, 3 mmol)
was added dropwise to a solution of dimethylindole 1 (0.53 g,
3 mmol) in dry 1,2ꢀdichloroethane (5 mL) at 5 °C. The reaction
mixture was stirred at 5 °C for 10 min. Then a solution of
(E)ꢀpentꢀ3ꢀenoic acid (0.3 mL, 3 mmol) and triethylamine
(1 mL, 3.2 mmol) in 1,2ꢀdichloroethane (7 mL) was added dropꢀ
wise at 5 °C. The reaction mixture was stirred for 1 h, and the
solution was concentrated in vacuo. The residue was purified by
column chromatography on silica gel (chloroform as the eluent).
The yield of the product was 0.26 g (28%), red crystals, m.p.
185—187 °C. IR, ν/cm–1: 1750, 1820 (C=O). 1H NMR, δ: 1.94
(dd, 3 H, Me, J1 = 7.0 Hz, J2 = 1.7 Hz); 2.43 (s, 3 H, Me); 3.74
(s, 3 H, NMe); 3.80 (s, 3 H, OMe); 6.26 (dq, 1 H, CH, J1 = 16.0 Hz,
3ꢀ(1,2ꢀDimethylꢀ1Hꢀindolꢀ3ꢀyl)ꢀ4ꢀ[(E)ꢀpropꢀ1ꢀenyl]furanꢀ
2,5ꢀdione (6) was synthesized according to a known procedure,10
m.p. 199—200 °C.
Xꢀray diffraction study. The unit cell parameters were meaꢀ
sured and the threeꢀdimensional Xꢀray diffraction data set was
collected on an EnrafꢀNonius CADꢀ4 automated diffractometer
(MoꢀKα radiation, graphite monochromator) at room temperaꢀ
ture. Darkꢀred transparent crystals of compound 5b (C19H19NO4,
M = 325.35) are triclinic, space group P–1, a = 10.463(3) Å,
b = 11.118(3) Å, с = 17.107(4) Å, α = 71.66(2)°, β = 76.54(3)°,
γ = 62.72(3)°, V = 1669.6(8) Å3, Z = 4, dcalc = 1.294 g cm–3
,
μ(MoKα) = 0.91 cm–1. The intensities of 6220 reflections were
measured in the angle range 2θ ≤ 50.04° using the ω/2θ scanning
technique from a single crystal of dimensions 0.42×0.25×0.25 mm;
5887 reflections (Rint = 0.071) were independent, 4057 reflecꢀ
tions were with F2 > 4σ(F2). The structure was solved by direct
methods using the SHELXTL program package20 and refined by
the fullꢀmatrix leastꢀsquares method based on F2 with anisotroꢀ
pic displacement parameters for nonhydrogen atoms using the
SHELXTL program package.20 All hydrogen atoms were locatꢀ
ed in difference Fourier maps. Then the atomic coordinates and
the isotropic temperature factors for all H atoms were refined by
the leastꢀsquares method using a riding model. In the last cycle
of the fullꢀmatrix refinement, the absolute shifts of all 434 variꢀ
able parameters of the crystal structure of 5b were smaller than
0.001σ. The final R factors were R1 = 0.054, wR1 = 0.150
based on 4057 observed reflections with I ≥ 2σ(I); R2 = 0.081,
wR2 = 0.163 based on all measured reflections; GOOF = 1.004.
J2 = 1.7 Hz); 6.79 (d, 2 H, HAr, J = 2.4 Hz); 6.90 (dd, 1 H, HAr
,
J1 = 8.9 Hz, J2 = 2.4 Hz); 7.10—7.30 (m, 2 H, HAr). Found (%):
C, 69.32; H, 5.41; N, 4.46. C18H17NO4. Calculated (%): C, 69.44;
H, 5.50; N, 4.50.
3ꢀ[(E)ꢀButꢀ1ꢀenyl]ꢀ3ꢀ(5ꢀmethoxyꢀ1,2ꢀdimethylꢀ1Hꢀindolꢀ4ꢀ
yl)furanꢀ2,5ꢀdione (5b) was synthesized by analogy with comꢀ
pound 5a from dimethylindole 1 and (E)ꢀhexꢀ3ꢀenoic acid. The
yield was 0.32 g (32.7%), red crystals, m.p. 175—177 °C. IR,
ν/cm–1: 1750, 1820 (C=O). 1H NMR, δ: 1.05 (t, 3 H, Me,
J = 7.4 Hz); 2.26 (q.d, 2 H, CH2, J1 = 7.3 Hz, J2 = 1.6 Hz); 2.44
(s, 3 H, Me); 3.75 (s, 3 H, NMe); 3.80 (s, 3 H, OMe); 6.22 (dt, 1 H,
CH, J1 = 16.0 Hz, J2 = 1.6 Hz); 6.78 (d, 1 H, HAr, J = 2.4 Hz);
6.90 (dd, 1 H, HAr, J1 = 8.9 Hz, J2 = 2.4 Hz); 7.16—7.30 (m, 2 H,
HAr). Found (%): C, 70.02; H, 5.63; N, 4.21. C19H19NO4. Calꢀ
culated (%): C, 70.14; H, 5.69; N, 4.30.