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dropwise 20% (w/v) NaOH (1.5 ml, 7.5 mmol). The mixture was stirred at
room temperature and monitored with TLC. When the reaction finished, the
residue was poured into saturated NH4Cl solution and filtered. The precipi-
tate was washed with water, cold ethanol, and then cold acetone and dried in
vacuum. The solid was purified by chromatography over silica gel using
CH2Cl2/CH3OH as the eluent to afford compounds 01, 02, 03, 04, 06, 08, 09,
10 and 12.
(2E,5E)-2,5-Bis(4-ethoxybenzylidene)cyclopentanone (A01): The product
was recrystallized from ethanol/water (9 : 1). Orange powder, 76% yield, mp
191—192 °C. 1H-NMR (CDCl3) d: 1.44 (6H, t, Jꢁ7 Hz, CH3ꢂ2), 3.08 (4H,
s, CH2–CH2), 4.09 (4H, q, Jꢁ7 Hz, O–CH2ꢂ2), 6.95 (4H, d, Jꢁ8.8 Hz, Ar–
H2,6ꢂ2), 7.54 (2H, s, Ar–CHꢁCꢂ2), 7.56 (4H, d, Jꢁ8.8 Hz, Ar–H3,5ꢂ2).
ESI-MS m/z: 349.15 (Mꢀ1)ꢀ, Calcd for C23H24O3: 348.43.
(2E,5E)-2,5-Bis(4-fluorobenzylidene)cyclopentanone (A02): The product
was recrystallized from ethanol/water (9 : 1). Yellow crystal, 88% yield, mp
239—240 °C. 1H-NMR (CDCl3) d: 3.10 (4H, s, CH2–CH2), 7.14 (4H, t,
Jꢁ8.4 Hz, Ar–H2,6ꢂ2), 7.59 (4H, t, Jꢁ9 Hz, Ar–H3,5ꢂ2), 7.61 (2H, s,
Ar–CHꢁCꢂ2). ESI-MS m/z: 297.13 (Mꢀ1)ꢀ, Calcd for C19H14F2O:
296.31.
COꢂ2), 7.52 (4H, d, Jꢁ8.4 Hz, Ar–H), 7.68 (2H, d, Jꢁ15.6 Hz, Ar–CHꢁ
Cꢂ2). ESI-MS m/z: 321.18 (Mꢀ1)ꢀ, Calcd for C21H24N2O: 320.43.
(1E,4E)-1,5-Bis(2-bromophenyl)penta-1,4-dien-3-one (B06): Orange pow-
1
der, 59% yield, mp 97 °C. H-NMR (CDCl3) d: 7.03 (2H, d, Jꢁ16 Hz, Cꢁ
CH–COꢂ2), 7.22—7.63 (8H, m, Ar–H), 8.09 (2H, d, Jꢁ16 Hz, Ar–CHꢁ
Cꢂ2). ESI-MS m/z: 393.10 (Mꢀ1)ꢀ, Calcd for C17H12Br2O: 392.08.
(1E,4E)-1,5-Bis(5-bromofuran-2-yl)penta-1,4-dien-3-one (B09): Yellow
powder, 79% yield, mp 138 °C. 1H-NMR (CDCl3) d: 6.44 (2H, d, Jꢁ3.6 Hz,
Ar–H4ꢂ2), 6.63 (2H, d, Jꢁ3.6 Hz, Ar–H3ꢂ2), 6.89 (2H, d, Jꢁ15.6 Hz, Cꢁ
CH–COꢂ2), 7.36 (2H, d, Jꢁ15.6 Hz, Ar–CHꢁCꢂ2). ESI-MS m/z: 372.88
(Mꢀ1)ꢀ, Calcd for C13H8Br2O3: 372.01.
(1E,4E)-1,5-Bis(3-bromophenyl)penta-1,4-dien-3-one (B10): Yellow pow-
der, 63% yield, mp 117 °C. 1H-NMR (CDCl3) d: 7.06 (2H, d, Jꢁ16 Hz, Cꢁ
CH–COꢂ2), 7.22—7.52 (8H, m, Ar–H), 7.65 (2H, d, Jꢁ16 Hz, Ar–CHꢁ
Cꢂ2). ESI-MS m/z: 392.95 (Mꢀ1)ꢀ, Calcd for C17H12Br2O: 392.08.
(1E,3E,6E,8E)-1,9-Diphenylnona-1,3,6,8-tetraen-5-one (B15): Yellow
powder, 90% yield, mp 142 °C. 1H-NMR (CDCl3) d: 6.58 (2H, d, Jꢁ15.2
Hz, CꢁCH–COꢂ2), 6.97—7.00 (4H, m, CꢁCH–CHꢁCꢂ2), 7.27—7.52
(12H, m, Ar–H). ESI-MS m/z: 287.07 (Mꢀ1)ꢀ, Calcd for C21H18O: 286.37.
(2E,6E)-2,6-Bis(4-ethoxybenzylidene)cyclohexanone (C01): Yellow pow-
der, 77% yield, mp 147-149 °C. 1H-NMR (CDCl3) d: 1.56 (6H, t, Jꢁ7.4 Hz,
CH3), 1.81 (2H, q, Jꢁ11.8 Hz, CH2), 3.08 (4H, t, Jꢁ6 Hz, C–CH2ꢂ2), 3.89
(4H, q, Jꢁ7.4 Hz, O–CH2ꢂ2), 6.79—7.21 (8H, m, Ar–H), 7.73 (2H, s,
Ar–CHꢁCꢂ2). ESI-MS m/z: 363.18 (Mꢄ1)ꢀ, Calcd for C24H26O3: 362.46.
(2E,6E)-2,6-Bis(4-fluorobenzylidene)cyclohexanone (C02): Yellow pow-
der, 69% yield, mp 156 °C. 1H-NMR (CDCl3) d: 1.81 (2H, q, Jꢁ12 Hz,
CH2), 2.90 (4H, t, Jꢁ5.4 Hz, CH2ꢂ2), 7.12 (4H, m, Ar–H2,6ꢂ2), 7.45 (4H,
m, Ar–H3,5ꢂ2), 7.76 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 311.11 (Mꢀ1)ꢀ,
Calcd for C20H16F2O: 310.34.
(2E,5E)-2,5-Bis(3,4,5-trimethoxybenzylidene)cyclopentanone (A03): Yel-
low powder, 90% yield, mp 202—204 °C. 1H-NMR (CDCl3) d: 3.15 (4H, s,
CH2–CH2), 3.91 (18H, s, O–CH3ꢂ6), 6.85 (4H, s, Ar–H2,6ꢂ2), 7.53 (2H, s,
Ar–CHꢁCꢂ2). ESI-MS m/z: 441.16 (Mꢀ1)ꢀ, Calcd for C25H28O7: 440.49.
(2E,5E)-2,5-Bis(4-(dimethylamino)benzylidene)cyclopentanone (A04):
1
Red powder, 71.1% yield, mp ꢃ260 °C. H-NMR (CDCl3) d: 2.54 (4H, s,
CH2–CH2), 2.98 (12H, s, N–CH3ꢂ4), 6.74 (4H, d, Jꢁ8.8 Hz, Ar–H2,6ꢂ2),
7.41 (4H, d, Jꢁ8.8 Hz, Ar–H3,5ꢂ2), 7.77 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z:
347.21 (Mꢀ1)ꢀ, Calcd for C23H26N2O: 346.47.
(2E,5E)-2,5-Bis(2-bromobenzylidene)cyclopentanone (A06): Yellow pow-
der, 87% yield, mp 163 °C. 1H-NMR (CDCl3) d: 2.98 (4H, s, CH2–CH2),
7.22 (2H, q, Jꢁ3.8 Hz, Ar–H4ꢂ2), 7.36 (2H, q, Jꢁ7.4 Hz, Ar–H6ꢂ2), 7.53
(2H, q, Jꢁ3.8 Hz, Ar–H5ꢂ2), 7.66 (2H, q, Jꢁ4 Hz, Ar–H3ꢂ2), 7.86 (2H, s,
Ar–CHꢁCꢂ2). ESI-MS m/z: 418.94 (Mꢀ1)ꢀ, Calcd for C19H14Br2O: 418.12.
(2E,5E)-2,5-Bis(2-fluoro-3-(trifluoromethyl)benzylidene)cyclopentanone
(A08): Yellow powder, 91% yield, mp 223 °C; 1H-NMR (CDCl3) d: 3.05
(4H, s, CH2–CH2), 7.32 (2H, t, Jꢁ8 Hz, Ar–H6ꢂ2), 7.64 (2H, t, Jꢁ7 Hz,
Ar–H5ꢂ2), 7.66 (2H, t, Jꢁ7 Hz, Ar–H4ꢂ2), 7.79 (2H, s, Ar–CHꢁCꢂ2).
ESI-MS m/z: 430.92 (Mꢄ1)ꢄ, Calcd for C21H12F8O: 432.31.
(2E,5E)-2,5-Bis((5-bromofuran-2-yl)methylene)cyclopentanone (A09): Yel-
low powder, 77% yield, mp 176 °C. 1H-NMR (CDCl3) d: 3.06 (4H, s,
CH2–CH2), 6.47 (2H, d, Jꢁ3.6 Hz, Ar–H4ꢂ2), 6.65 (2H, d, Jꢁ3.6 Hz,
Ar–H3ꢂ2), 7.25 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 398.81 (Mꢀ1)ꢀ,
Calcd for C15H10Br2O3: 398.05.
(2E,6E)-2,6-Bis(3,4,5-trimethoxybenzylidene)cyclohexanone (C03): Yel-
low powder, 71% yield, mp 196 °C. 1H-NMR (CDCl3) d: 1.83 (2H, t, Jꢁ5.6
Hz, CH2), 2.97 (4H, t, Jꢁ5.2 Hz, C–CH2ꢂ2), 3.90 (18H, s, O–CH3ꢂ6), 6.71
(4H, s, Ar–H), 7.73 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 455.15 (Mꢀ1)ꢀ,
Calcd for C26H30O7: 454.51.
(2E,6E)-2,6-Bis(4-(dimethylamino)benzylidene)cyclohexanone (C04): Yel-
1
low powder, 55% yield, mp 160 °C. H-NMR (CDCl3) d: 1.82 (2H, t, Jꢁ6
Hz, CH2), 2.93 (4H, t, Jꢁ5.6 Hz, C–CH2ꢂ2), 3.01 (12H, s, N–CH3ꢂ4), 6.72
(4H, d, Jꢁ8.8 Hz, Ar–H2.6ꢂ4), 7.45 (4H, d, Jꢁ8.8 Hz, Ar–H3.5ꢂ4), 7.76
(2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 361.24 (Mꢀ1)ꢀ, Calcd for C24H28N2O:
360.49.
(2E,6E)-2,6-Bis(2-bromobenzylidene)cyclohexanone (C06): Yellow pow-
der, 83% yield, mp 120 °C. 1H-NMR (CDCl3) d: 1.75 (2H, q, Jꢁ9.3 Hz,
CH2), 2.75 (4H, t, Jꢁ6.1 Hz, C–CH2ꢂ2), 7.18—7.35 (6H, m, Ar–H), 7.64
(2H, m, Ar–H), 7.86 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 432.98 (Mꢀ1)ꢀ,
Calcd for C20H16Br2O: 432.15.
(2E,5E)-2,5-Bis(3-bromobenzylidene)cyclopentanone (A10): Yellow pow-
der, 91% yield, mp 186 °C. 1H-NMR (CDCl3) d: 3.12 (4H, s, CH2–CH2),
7.30 (2H, t, Jꢁ15.6 Hz, Ar–H5ꢂ2), 7.50—7.52 (6H, m), 7.73 (2H, s, Ar–
CHꢁCꢂ2). ESI-MS m/z: 418.98 (Mꢀ1)ꢀ, Calcd for C19H14Br2O: 418.12.
(2E,5E)-2,5-Bis(4-(3-(dimethylamino)propoxy)benzylidene)cyclopen-
(2E,6E)-2,6-Bis((5-bromofuran-2-yl)methylene)cyclohexanone
(C09):
Yellow powder, 61% yield, mp 127 °C. 1H-NMR (CDCl3) d: 1.90 (2H, q, Jꢁ
9.4 Hz, CH2), 2.92 (4H, m, Jꢁ6.2 Hz, C–CH2ꢂ2), 6.44 (2H, d, Jꢁ3.6 Hz,
Ar–H4ꢂ2), 6.66 (2H, d, Jꢁ3.6 Hz, Ar–H3ꢂ2), 7.43 (2H, s, Ar–CHꢁCꢂ2).
ESI-MS m/z: 412.87 (Mꢀ1)ꢀ, Calcd for C16H12Br2O3: 412.07.
1
tanone (A12): Yellow powder, 72% yield, mp 154 °C. H-NMR (CDCl3) d:
1.98 (4H, m, CH2ꢂ2), 2.26 (12H, s, N–CH3ꢂ4), 2.46 (4H, t, Jꢁ7.4 Hz,
CH2–Nꢂ2), 3.08 (4H, s, CH2–CH2), 4.07 (4H, t, Jꢁ6.2 Hz, O–CH2ꢂ2),
6.96 (4H, d, Jꢁ8.8 Hz, Ar–H2,6ꢂ2), 7.73 (2H, s, Ar–CHꢁCꢂ2), 7.56 (4H,
d, Jꢁ8.8 Hz, Ar–H3,5ꢂ2). ESI-MS m/z: 463.33 (Mꢀ1)ꢀ, Calcd for
C29H38N2O3: 462.62.
(2E,6E)-2,6-Bis(3-bromobenzylidene)cyclohexanone (C10): Yellow pow-
der, 52% yield, mp 112 °C. 1H-NMR (CDCl3) d: 1.81 (2H, s, CH2), 2.90
(4H, s, C–CH2ꢂ2), 7.28 (2H, t, Jꢁ7.8 Hz, Ar–H5ꢂ2), 7.37 (2H, d, Jꢁ7.6
Hz, Ar–H6ꢂ2), 7.47 (2H, d, Jꢁ7.6 Hz, Ar–H4ꢂ2), 7.59 (2H, s, Ar–H2ꢂ2),
7.70 (2H, s, Ar–CHꢁCꢂ2). ESI-MS m/z: 433.32 (Mꢀ1)ꢀ, Calcd for
C20H16Br2O: 432.15.
General Procedure of 07 and 11 A solution of 3,4-dihydro-a-pyran
(22 mmol) in dichloromethane (20 ml) was added dropwise onto a well-
stirred suspension of hydroxyl benzaldehyde (14.4 mmol) and pyridinium p-
toluenesulfonate (0.16 mmol) in the same solvent (40 ml). The mixture was
stirred at room temperature and monitored by TLC, then was washed with
saturated NaHCO3 solution (50 mlꢂ3) and brine (50 mlꢂ3) and dried over
Na2SO4. Evaporation of the solvent gave crude product which was purified
by column chromatography on silica gel (hexane/ethyl acetate, 7 : 3, as elu-
ent) to obtain the mediate 4-(tetrahydropyran-2-yloxy) benzaldehyde as a
lightly yellow oil (69—78% yield).
(2E,5E)-2,5-Bis((E)-3-phenylallylidene)cyclopentanone (A15): Yellow pow-
der, 81.1% yield, mp 229 °C. 1H-NMR (CDCl3) d: 2.93 (4H, s, CH2–CH2),
6.98 (4H, t, Jꢁ6.8 Hz, Ar–H3,5ꢂ2), 7.26—7.39 (8H, m), 7.53(4H, t). ESI-MS
m/z: 313.11 (Mꢀ1)ꢀ, Calcd for C23H20O: 312.40.
(1E,4E)-1,5-Bis(4-ethoxyphenyl)penta-1,4-dien-3-one (B01): Yellow pow-
der, 77% yield, mp 123 °C. 1H-NMR (CDCl3) d: 1.39 (6H, t, Jꢁ8.2 Hz,
CH3ꢂ2), 4.10 (4H, q, Jꢁ8.2 Hz, O–CH2ꢂ2), 6.99 (4H, m, Jꢁ7.2, Ar–H),
7.14 (2H, d, Jꢁ16 Hz, CH–CꢁOꢂ2), 7.68—7.74 (6H, m). ESI-MS m/z:
323.16 (Mꢀ1)ꢀ, Calcd for C21H22O3: 322.40.
(1E,4E)-1,5-Bis(4-fluorophenyl)penta-1,4-dien-3-one (B02): The product
was recrystallized from ethanol/water (9 : 1). Yellow crystal, 67% yield, mp
152 °C [lit.22) 152—154 °C].
(1E,4E)-1,5-Bis(3,4,5-trimethoxyphenyl)penta-1,4-dien-3-one (B03): Yel-
low powder, 81% yield, mp 136 °C. H-NMR (CDCl3) d: 3.89 (18H, s, O–
CH3ꢂ6), 6.84 (4H, s, Ar–H), 6.98 (2H, q, Jꢁ16 Hz, CH–CꢁOꢂ2), 7.65
(2H, q, Jꢁ16 Hz, Ar–CHꢁCꢂ2). ESI-MS m/z: 415.14 (Mꢀ1)ꢀ, Calcd for
C23H26O7: 414.45.
(1E,4E)-1,5-Bis(4-(dimethylamino)phenyl)penta-1,4-dien-3-one (B04): Red
powder, 91% yield, mp 185 °C. 1H-NMR (CDCl3) d: 3.04 (12H, s, N–
CH3ꢂ4), 6.69 (4H, d, Jꢁ8.4 Hz, Ar–H), 6.90 (2H, d, Jꢁ15.6 Hz, CꢁCH–
A mixture of protected derivative (6.94 mmol) and ketone (3.47 mmol) in
C2H5OH (10 ml) was stirred at room temperature for 20 min; then 20% (w/v)
NaOH (0.7 ml, 3.47 mmol) was added dropwise. After stirring for 60 min,
the mixture was treated with 100 ml cold water and filtered. The residue was
washed with ethanol and acetone and dried in vacuum. The product was pu-
rified by column chromatography on silica gel (hexane/ethyl acetate 9 : 1) to
obtain 07 and 11.
1
(2E,5E)-2,5-Bis(4-(tetrahydro-2H-pyran-2-yloxy)benzylidene)cyclopen-