5382 J . Org. Chem., Vol. 61, No. 16, 1996
Patonay et al.
1H), 4.60 (d, J ) 12.3 Hz, 1H), 3.68 (br s, 1H, D2O exchange-
able), 2.39 (s, 3H). Anal. Calcd for C16H14O3 (254.29): C,
75.57; H, 5.55. Found: C, 75.33; H, 5.61.
toluene) to yield 0.40 g (6.5%) enone 8c as a yellow oil and
2,2-dimethylchromanone (2.7 g, 44%) as main product.
8c: IR (neat) 2976, 2913, 1641, 1583, 1466, 1444, 1363,
t r a n s-3′,4′-(E t h y le n e d io x y)-3-h yd r o xy -7-m e t h oxy -
m eth oxyfla va n on e (tr a n s-2i): Yields: 44% (method A,
stirring period: 3 min), 36% (method B, stirring period: 21
h); mp: 153-155 °C (EtOH), colorless crystals. IR 3448, 2928,
2880, 1682, 1610, 1658, 1512, 1446, 1434, 1296, 1254, 1208,
1293, 1242, 1222, 1158, 1014, 796, 756 cm-1
.
1H NMR δ 12.82
(s, 1H, D2O exchangeable), 7.87 (dd, J ) 8.0, 1.7 Hz, 1H), 7.34
(ddd, 1H), 6.97 (dd, J ) 8.4, 1.2 Hz, 1H), 6.87 (ddd, 1H), 6.79
(m, 1H), 2.21 (d, J ) 1.3 Hz, 1H), 2.04 (d, J ) 1.3 Hz, 1H). 13
C
NMR δ 196.6, 163.5, 158.0, 135.9, 135.8, 130.0, 120.7, 120.1,
118.7, 118.5, 28.0. 21.2. MS 176 (M+•, 4), 161 (100), 131 (3).
121 (31), 120 (6), 89 (9), 83 (14), 65 (20).
1154, 1114, 1094, 1064, 1034, 1012, 856, 800 cm-1 1H NMR
.
δ 7.86 (d, J ) 8.4 Hz, 1H), 7.10 (d, J ) 1.4 Hz, 1H), 7.05 (dd,
J ) 8.1, 1.4 Hz, 1H), 6.94 (d, J ) 8.1 Hz), 6.76 (dd, J ) 8.4,
1.5 Hz, 1H), 6.68 (d, J ) 1.5 Hz, 1H), 5.20 (s, 2H), 5.01 (d, J
) 12.1 Hz, 1H), 4.55 (d, J ) 12.1 Hz, 1H), 4.29 (s, 4H), 3.70 (s,
1H, D2O exchangeable), 3.70 (s, 3H). Anal. Calcd for C19H18O7
(358.35): C, 63.68; H, 5.06. Found: C, 63.82; H, 5.03.
1-[2-Hyd r oxy-4-(tosyloxy)p h en yl]-3-m eth yl-2-bu ten -1-
on e (8f). A mixture of 1-(2,4-dihydroxyphenyl)-3-methyl-2-
propen-1-one (8e)27 (956 mg, 5.00 mmol), p-toluenesulfonyl
chloride (1.35 g, 7.08 mmol), powdered anh K2CO3 (800 mg,
5.79 mmol), and absolute acetone (50 mL) was stirred at room
temperature for 18 h, poured into water (500 mL), extracted
with CH2Cl2 (3 × 150 mL), and dried. After concentration
under reduced pressure the obtained residue was submitted
to silica gel chromatography (eluent: hexane-acetone ) 2:1,
v/v) to give 391 mg (23%) of tosylate 8f as pale yellow crystals,
mp 109-111 °C (hexane-absolute EtOH). IR 3060, 3040,
2932, 1640, 1578, 1504, 1494, 1446, 1366, 1308, 1294, 1228,
tr a n s-3,7,3′,4′-Tet r a h yd r oxyfla va n on e or (()-F u st in
(tr a n s-2j). A sample of 545 mg (2.00 mmol) of 2′,4′,3,4-
tetrahydroxychalcone (1j) was treated with DMD (20 mL) in
acetone solution. Fresh batches of dioxirane were added
repeatedly until complete consumption of the starting chal-
cone, and the reaction mixture was concentrated (bath tem-
perature ) 25 °C) and submitted to silica gel chromatography
(toluene-absolute methanol ) 5:1, v/v) to give 291 mg (50%)
of dihydroflavonol 2j; mp 210-220 °C dec (lit.41 mp 211 °C),
brownish powder. IR 3412 br, 3260 br, 1676, 1610, 1522, 1464,
1
1192, 1176, 1122, 1092, 976, 868, 850, 834, 812, 728 cm-1. H
NMR (Me2CO-d6) δ 13.00 (s, 1H, D2O exchangeable), 8.02 (dd,
J ) 9.3, 1.0 Hz, 1H), 7.80 (d, J ) 8.0 Hz, 2H), 7.50 (d, J ) 8.0
Hz, 2H), 6.99 (m, 1H), 6.63 (dd, J ) 9.3, 2.4 Hz, 1H), 6.61 (d,
J ) 1.0 Hz, 1H), 2.47 (s, 3H), 2.22 (d, J ) 2.3 Hz, 3H), 2.06 (d,
3H, overlaps with the solvent signal). Anal. Calcd for
C18H18O5S (346.41): C, 62.41; H, 5.24; S, 9.26. Found: C,
62.19; H, 5.27; S, 9.38.
Gen er a l P r oced u r e for th e Oxid a tion of 1-(2-Hyd r oxy-
p h en yl)-2-p r op en -1-on es 8 by Dim eth yld ioxir a n e. To a
solution of enone 8 (2.00-2.50 mmol) in CH2Cl2 (10 mL) was
added DMD (20 mL) as acetone solution (0.08-0.10 M) and
allowed to stand at 0-5 °C. Addition of DMD was repeated
in 12 h intervals, and the reaction was monitored by TLC
(hexane-acetone ) 4:1, v/v). The solvent was removed in
vacuo (bath temperature ) 25 °C), and the residue was
submitted to silica gel chromatography. Further experimental
details are given in Table 3.
3-Hyd r oxych r om a n on e (10a ) a n d 2-(h yd r oxym eth yl)-
3-cou m a r a n on e (11a ), cf. Ta ble 3, en tr y 2, were obtained
from 8a (370 mg, 2.50 mmol) according to the above general
procedure with 8:1 (v/v) toluene-ethyl acetate mixture as
eluent.
10a : Yield: 5.1%; mp 56-57.5 °C (lit.24 mp 57-58 °C); Rf
) 0.24. 1H NMR δ 7.88 (dd, J ) 7.8, 1.7 Hz, 1H), 7.53 (ddd,
1H), 7.07 (t, 1H), 6.91 (d, J ) 8.3 Hz), 5.65 (ABX m, 2H), 4.15
(ABX dd, 1H), 3.65 (s, 1H, D2O exchangeable).
1322, 1266 br, 1160, 1108, 1016, 992, 806 cm-1
.
1H NMR
(DMSO-d6) δ 10.60 (s, 1H, D2O exchangeable), 9.00, 8.96 (2 ×
s, 2H, D2O exchangeable), 7.92 (d, J ) 8.7 Hz, 1H), 6.89 (m,
1H), 6.75 (m, 2H), 6.53 (dd, J ) 8.7, 2,2 Hz, 1H), 6.30 (d, J )
2.2 Hz, 1H), 5.49 (d, J ) 5.5 Hz, 1H, D2O exchangeable), 4.97
(d, J ) 11.4 Hz, 1H), 4.41 (dd, J ) 11.4, 5.5 Hz, 1H).
tr a n s-3,7-Dih yd r oxy-3′,4′-(et h ylen ed ioxy)fla va n on e
(tr a n s-2k ). A mixture of 156 mg (0.435 mmol) trans-3′,4′-
(ethylenedioxy)-3-hydroxy-7-(methoxymethoxy)flavanone (trans-
2i), Amberlyst 15 (0.3 g) and methanol (10 mL) was stirred at
50 °C for 3.5 h. The resin was removed by filtration and
washed with hot methanol (3 × 10 mL), and the combined
filtrate was concentrated under reduced pressure. The residue
was crystallized from diisopropyl ether to afford 104 mg (76%)
brownish powder, mp 227-230 °C. IR 3446, 2938, 2878, 1676,
1654, 1612, 1510, 1466, 1436, 1384, 1310, 1260, 1156, 1106,
1064, 1008, 924, 890, 808 cm-1
.
1H NMR (DMSO-d6) δ 10.62
(br s, 1H, D2O exchangeable), 7.53 (d, J ) 9.1 Hz, 1H), 7.05
(d, J ) 1.4 Hz, 1H), 6.99 (dd, J ) 9.1, 1.4 Hz, 1H), 6.88 (d, J
) 9.1 Hz, 1H), 6.53 (dd, J ) 9.3, 2.4 Hz, 1H), 6.32 (d, J ) 2.4
Hz, 1H), 5.05 (d, J ) 11.6 Hz, 1H), 4.48 (d, J ) 11.6 Hz, 1H).
Anal. Calcd for C17H14O6 (314.30): C, 64.97; H, 4.49. Found:
C, 64.95; H, 4.43.
1-(2-Hyd r oxyp h en yl)-2-p r op en -1-on e (8a ). A mixture of
2′-hydroxyacetophenone (6.0 mL, 49.8 mmol), dimethylammo-
nium chloride (5.55 g, 68.0 mmol), paraformaldehyde (2.01 g),
2-propanol (10 mL), and concd hydrochloric acid (0.2 mL) was
refluxed for 1 h and was allowed to stand in the refrigerator
overnight. The colorless precipitate was collected by filtration,
washed with diethyl ether (4 × 30 mL), dissolved in water (750
mL), and steam-distilled. The distillate was extracted with
CH2Cl2 (3 × 150 mL), dried, and concentrated under reduced
pressure. Silica gel chromatography (eluent: toluene) of the
residue afforded 1.20 g (16%) of enone 8a as a yellow oil (lit.25
bp 67-68 °C/1-2 Torr). IR (neat) 3046 br, 1644, 1634, 1614,
1592, 1486, 1446, 1410, 1358, 1288, 1240, 1208, 1158, 1000,
11a : Yield: 53%; mp 95-98 °C (hexane-ethyl acetate); Rf
) 0.10. IR 3424, 2922, 1712, 1616, 1478, 1326, 1310, 1196,
1146, 1092, 1022, 758 cm-1
.
1H NMR δ 7.59-7.68 (m, 2H),
7.06-7.19 (m, 2H), 4.68 (ABX dd, 1H), 4.10 (ABX m, 2H), 2.24
(s, 1H, D2O exchangeable). 13C NMR δ 184.2, 173.0, 138.1,
123.9, 121.8, 121.0, 113.3, 85.9, 61.5. Anal. Calcd for C9H8O3
(164.16): C, 65.85; H, 4.91. Found: C, 65.67; H, 4.79.
cis,t r a n s-3-H yd r oxy-7-m e t h oxy-2-m e t h ylch r om a n -
on e (10b) a n d er yth r o,th r eo-2-(1-h yd r oxyeth yl)-6-m eth -
oxy-3-cou m a r a n on e (11b), cf. Ta ble 3, en tr y 3, were
obtained from 8b26 (384 mg, 2.00 mmol) according to the above
general procedure with 4:1 (v/v) hexane-acetone mixture as
eluent.
976, 832, 752, 716 cm-1
.
1H NMR δ 12.53 (s, 1H, D2O
exchangeable), 7.80 (dd, J ) 8.0, 1.5 Hz, 1H), 7.55 (ddd, 1H),
7.50 (dd, J ) 16.9, 10.5 Hz, 1H), 6.87-7.03 (m, 2H), 6.56 (dd,
J ) 16.9, 1.6 Hz, 1H), 5.96 (dd, J ) 10.5, 1.6 Hz, 1H). Anal.
Calcd for C9H8O2 (148.16): C, 72.96; H, 5.44. Found: C, 73.11;
H, 5.19.
cis,tr a n s-10b: Yield: 4.9%; colorless crytals; mp 126-148
°C (lit.17a mp 152 °C for trans-10b diastereomer, but stereo-
chemistry based only on chemical properties); Rf ) 0.24. IR
3410, 2986, 2942, 2844, 1668, 1616, 1574, 1446, 1384, 1252,
1198, 1164, 1102, 1070, 996, 980, 840 cm-1 1H NMR: trans-
.
1-(2-Hydr oxyph en yl)-3-m eth yl-2-bu ten -1-on e (8c). Phen-
yl 3-methyl-2-butenoate (6.20 g, 35.18 mmol) was treated with
AlCl3 (6.51 g, 48.82 mmol) according to the literature proce-
dure.29 After workup and removal of the diethyl ether the
residue was submitted to column chromatography (eluent:
10b δ 4.12 (d, J ) 11.8 Hz, 1H), 3.84 (s, 3H), 1.64 (d, J ) 6.1
Hz, 3H); cis-10b δ 3.91 (d, J ) 3.7 Hz, 1H), 3.81 (s, 3H), 1.51
(d, J ) 5.2 Hz, 3H). Unassigned signals: δ 7.81 (d, J ) 8.8
Hz, 1H), 6.63 (dd, J ) 8.8, 2.4 Hz, 1H), 6.44 (d, J ) 2.4 Hz,
1H), 4.22 (m, 1H). The diastereomeric ratio trans-10b:cis-10b
) 85:15 was determined by 1H NMR analysis of the 7-MeO
and 2-Me signals. Anal. Calcd for C11H12O4 (208.22): C, 63.45;
H, 5.81. Found: C, 63.27; H, 5.90.
(41) Fourie, T. G.; Ferreira, D.; Roux, D. G. J . Chem. Soc., Perkin
Trans. 1 1977, 125.