New method for the synthesis of indenes
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 11, November, 2002 2095
from the residue by chromatography (CH2Cl2 as the eluent).
The yield was 50%, colorless oil. Found (%): C, 54.75; H, 5.79.
124.92; 127.61; 127.74; 128.10; 129.24; 129.28; 133.12; 133.31;
133.90; 134.48; 140.65; 140.90; 141.05; 142.43; 146.75; 160.55.
C18H22O3SSi. Calculated (%): C, 54.51; H, 5.72. IR, ν/cm–1
1698 (HC=O). 1H NMR, δ: 0.34 (s, 9 H, SiMe3); 3.24 (dd, 1 H,
CH2CH, J = 11.9 Hz, J = 1.3 Hz); 3.40 (dd, 1 H, CH2CH, J =
11.9 Hz, J = 8.8 Hz); 3.42 (dd, 1 H, CH2CH, J = 8.8 Hz, J =
1.3 Hz); 6.72 (d, 1 H, H of thiophene, J = 5.0 Hz); 7.26—7.31
(m, 2 H, Ar); 7.38 (d, 1 H, H of thiophene, J = 5.0 Hz);
7.39—7.43 (m, 1 H, Ar); 7.53—7.55 (m, 2 H, Ar); 9.70 (s, CHO).
13C NMR, δ: –0.98 (SiMe3); 26.05 (CH2CH); 55.88 (CH2CH);
126.95; 128.74; 130.85; 132.53; 134.07; 137.89; 141.59; 146.49;
181.66 (CHO).
Cyclization of aldehydes 3—9 (general procedure). A solution
of the corresponding aldehyde (1 mmol) in THF (5 mL) was
added to a solution of ButOK (0.235 g, 2.1 mmol) in THF
(10 mL). The course of the reaction was monitored by TLC. The
reaction mixture was stirred for 5 min, poured into 0.5 M hydroꢀ
chloric acid (20 mL), and extracted with ether (2×10 mL). The
extract was dried with CaCl2 and concentrated in vacuo. The
product was purified by passing through a short column with
silica gel (CH2Cl2—hexane, 3 : 1, as the eluent).
:
5,6ꢀDimethoxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (13). The yield
was 71%, colorless crystals, m.p. 126—128 °C. Found (%):
C, 64.54; H, 5.10. C17H16O4S. Calculated (%): C, 64.40; H, 5.24.
1H NMR, δ: 3.53 (d, 2 H, CH2, J = 1.8 Hz); 3.85 (s, 6 H, 5ꢀ and
6ꢀMeO); 6.95 (s, 1 H, H(7)); 6.99 (s, 1 H, H(4)); 7.46—7.50 (m,
2 H, Ph); 7.52—7.56 (m, 1 H, Ph); 7.60 (t, 1 H, H(3), J =
1.8 Hz); 7.91—7.94 (m, 2 H, Ph). 13C NMR, δ: 38.04 (CH2);
56.00 (MeO); 55.10 (MeO); 112.65; 115.25; 127.80; 129.75;
133.62; 140.90; 141.12; 141.82; 144.86; 146.28; 148.29; 153.36.
A mixture of 4,5,6ꢀtrimethoxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene
(14a) and 5,6,7ꢀtrimethoxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (14b)
(1 : 1.4). The yield was 70%, colorless oil. Found (%): C, 62.41;
H, 5.24. C18H18O5S. Calculated (%): C, 62.52; H, 5.38.
1H NMR, δ: 3.56 (dd, 2 H, CH2 (14a), J = 1.8 Hz, J = 0.8 Hz);
3.58 (d, 2 H, CH2 (14b), J = 1.8 Hz); 3.82, 3.83, 3.84, 3.85,
3.92, and 3.99 (all s, 3 H each, MeO); 6.75 (s, 1 H, H(7) (14a));
6.82 (s, 1 H, H(4) (14b)); 7.48—7.53 (m, 4 H, Ph (14a), Ph
(14b)); 7.54—7.59 (m, 3 H, H(3) (14b), Ph (14a), Ph (14b));
7.78 (t, 1 H, H(3) (14a), J = 1.8 Hz); 7.93—7.96 (m, 4 H, Ph
(14a), Ph (14b)). 13C NMR, δ: 35.31 (CH2 (14a)); 38.57
(CH2 (14b)); 55.48; 56.84; 58.25; 59.10; 60.22; 60.81; 105.64;
107.32; 115.47; 118.44; 128.21; 128.52; 129.72; 129.85; 133.42;
133.64; 140.25; 140.67; 141.28; 141.56; 146.75; 147.14; 151.12;
151.27; 152.13; 152.53.
5,6ꢀMethylenedioxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (15). The
yield was 71%, colorless crystals, m.p. 176—178 °C. Found (%):
C, 64.01; H, 4.12. C16H12O4S. Calculated (%): C, 63.99; H, 4.03.
1H NMR, δ: 3.52 (dd, 2 H, CH2, J = 2.1 Hz, J = 0.8 Hz); 5.97
(s, 2 H, OCH2O); 6.88 (s, 1 H, H(7)); 6.93 (s, 1 H, H(4));
7.49—7.53 (m, 2 H, Ph); 7.55—7.59 (m, 2 H, Hp (Ph), H(3));
7.93—7.96 (m, 2 H, Ph). 13C NMR, δ: 37.94 (CH2); 102.58
(OCH2O); 112.84; 113.45; 127.65; 129.36; 133.58; 141.05;
141.28; 141.67; 143.95; 145.93; 147.48; 151.22.
A mixture of 5ꢀphenylsulfonylꢀ4Hꢀcyclopenta[b]thiophene
(16a) and 5ꢀphenylsulfonylꢀ6Hꢀcyclopenta[b]thiophene (16b)
(1.7 : 1). The yield was 60%, colorless oil. Found (%): C, 59.52;
H, 3.84. C13H10O2S2. Calculated (%): C, 59.60; H, 4.06.
1H NMR, δ: 3.49 (d, 2 H, CH2 (16a), J = 1.8 Hz); 3.62 (d, 2 H,
CH2 (16b), J = 1.8 Hz); 7.03 (d, 1 H, H of thiophene (16a), J =
4.8 Hz); 7.05 (d, 1 H, H of thiophene (16b), J = 5.2 Hz); 7.31
(d, 1 H, H of thiophene (16b), J = 5.2 Hz); 7.43 (d, 1 H, H of
thiophene (16a), J = 4.8 Hz); 7.49—7.54 (m, 4 H, Ph (16a), Ph
(16b)); 7.56—7.60 (m, 2 H, Ph (16a), Ph (16b)); 7.66 (t, 1 H,
=CH (16b), J = 1.8 Hz); 7.70 (t, 1 H, =CH (16a), J = 1.8 Hz);
7.94—7.97 (m, 4 H, Ph (16a), Ph (16b)). 13C NMR, δ: 35.27
(CH2 (16a)); 35.87 (CH2 (16b)); 120.11; 122.29; 127.52; 128.01;
129.28; 129.49; 131.33; 133.14; 136.39; 137.36; 141.20; 141.25;
141.56; 144.84; 145.96; 146.37; 147.83; 151.32.
2ꢀPhenylsulfonylꢀ1Hꢀindene (10). The yield was 94%, colorꢀ
less crystals, m.p. 121—122 °C (cf. lit. data27: m.p. 120—122 °C).
1H NMR, δ: 3.63 (d, 2 H, CH2, J = 1.7 Hz); 7.31—7.36 (m, 2 H);
7.42—7.44 (m, 1 H); 7.51—7.55 (m, 3 H); 7.58—7.62 (m, 1 H,
Ar); 7.70 (t, 1 H, J = 1.7 Hz); 7.97—7.99 (m, 2 H, Ar). 13C NMR,
δ: 37.86 (CH2); 124.00; 124.35; 127.39; 127.74; 128.28; 129.30;
133.35; 140.62; 140.86; 141.00; 144.30; 145.26.
A mixture of 5ꢀfluoroꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (11a) and
6ꢀfluoroꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (11b) (1 : 1.6). The yield
was 84%, colorless crystals, m.p. 115—117 °C. Found (%):
C, 65.90; H, 4.07. C15H11FO2S. Calculated (%): C, 65.68;
H, 4.04. 1H NMR, δ: 3.60 (d, 2 H, CH2 (11a), J = 1.1 Hz); 3.62
(br.s, 2 H, CH2 (11b)); 7.00—7.07 (m, 2 H, H(6) (11a), H(5)
3
(11b)); 7.13 (dd, 1 H, H(7) (11b), JH,F = 9.1 Hz, J = 1.9 Hz);
7.19 (dd, 1 H, H(4) (11a), 3JH,F = 8.5 Hz, J = 2.5 Hz); 7.36 (dd,
4
1 H, H(7) (11a), J = 8.2 Hz, JH,F = 4.9 Hz); 7.46 (dd, 1 H,
H(4) (11b), J = 8.2 Hz, 4JH,F = 4.9 Hz); 7.52—7.56 (m, 4 H, Ph
(11a), Ph (11b)); 7.58—7.62 (m, 3 H, H(3) (11a), Ph (11a), Ph
(11b)); 7.64 (t, 1 H, H(3) (11b), J = 1.1 Hz); 7.96—7.99 (m,
4 H, Ph (11a), Ph (11b)). 13C NMR, δ: 37.29 (CH2 (11a));
4
38.01 (d, CH2 (11b), JC,F = 2.6 Hz); 110.80 (d, C(6) (11a),
3
3JC,F = 23.5 Hz); 112.09 (d, C(7) (11b), JC,F = 23.5 Hz);
3
114.87 (d, C(5) (11b), JC,F = 23.5 Hz); 115.37 (d, C(4) (11a),
4
3JC,F = 23.5 Hz); 125.10 (d, C(4) (11b), JC,F = 10.4 Hz);
4
125.38 (d, C(7) (11a), JC,F = 9.1 Hz); 127.72; 127.81; 129.34;
1
129.36; 133.42; 133.53; 140.10; 162.96 (d, C(5) (11a), JC,F
–217.8 Hz); 165.56 (d, C(6) (11b), 1JC,F = –242.6 Hz).
=
A mixture of 5ꢀmethoxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (12a)
and 6ꢀmethoxyꢀ2ꢀphenylsulfonylꢀ1Hꢀindene (12b) (1 : 2.5). The
yield was 72%, colorless oil. 1H NMR, δ: 3.56 (dd, 2 H, CH2
(12a), J = 1.9 Hz, J = 0.6 Hz); 3.59 (d, 2 H, CH2 (12b), J =
1.9 Hz); 3.81 (s, 6 H, MeO (12b), MeO (12a)); 6.86—6.90 (m,
2 H, H(4) (12a), H(5) (12b)); 7.03 (m, 1 H, H(6) (12a)); 7.30
(dd, 1 H, H(7) (12a), J = 8.3 Hz); 7.41 (d, 1 H, H(4) (12b), J =
8.6 Hz); 7.50—7.55 (m, 4 H, Ph (12a), Ph (12b)); 7.56—7.60
(m, 3 H, H(3) (12a), Hp, Ph (12a), Hp, Ph (12b)); 7.64 (t, 1 H,
H(3) (12b), J = 1.9 Hz); 7.95—7.98 (m, 4 H, Ph (12a), Ph
(12b)); 7.98 (d, 1 H, H(7) (12b), J = 1.8 Hz). 13C NMR, δ:
37.19 (CH2 (12a)); 37.91 (CH2 (12b)); 55.10 (MeO (12a));
55.55 (MeO (12b)); 108.69; 110.28; 113.62; 115.14; 124.78;
Reaction of 2ꢀphenylsulfonylꢀ1Hꢀindene (10) with methylꢀ
magnesium iodide. A solution of MeI (0.93 mL, 2.12 g, 15 mmol)
in THF (5 mL) was added dropwise with stirring to a suspension
of Mg (0.73 g, 15 mmol) in anhydrous THF (5 mL) and the
reaction mixture was refluxed for 30 min. Then Ni(acac)2
(0.129 g, 0.5 mmol) or Fe(acac)3 (0.177 g, 0.5 mmol) and a
solution of indene 10 (1.28 g, 5 mmol) in THF (10 mL) were
added. The reaction mixture was refluxed with stirring for 12 h,
decomposed with hydrochloric acid, and extracted with ether
(2×15 mL). The extract was dried with CaCl2 and concentrated
in vacuo. The product was isolated from the residue by passing