Synthesis of pyrone carbaldehydes, pyrone sulfonium ylides and related epoxides

Article abstract of DOI:10.1002/jhet.79

Hexaminium salts of 4-pyrones 3a, b were synthesized by treatment of 2-(4-bromomethylphenyl)-6- methyl-4H-pyran-4-one 2a and 2-(4-bromomethylphenyl)- 6-phenyl-4H-pyran-4-one 2b with hexamethyl- enetetramine in chloroform in 71 and 84% yields respectively.

Full text of DOI:10.1002/jhet.79

268
Synthesis of Pyrone Carbaldehydes, Pyrone Sulfonium Ylides and
Related Epoxides
Vol 46
Aziz Shahrisa* and Mahnaz Saraei
Department of Organic Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz 51664, Iran
*E-mail: ashahrisa@yahoo.com
Received September 1, 2008
DOI 10.1002/jhet.79
Published online 13 April 2009 in Wiley InterScience (www.interscience.wiley.com).
Hexaminium salts of 4-pyrones 3a, b were synthesized by treatment of 2-(4-bromomethylphenyl)-6-
methyl-4H-pyran-4-one 2a and 2-(4-bromomethylphenyl)-6-phenyl-4H-pyran-4-one 2b with hexamethyl-
enetetramine in chloroform in 71 and 84% yields respectively. Hydrolysis of 3a and 3b in EtOH:H2O
produced the corresponding aldehydes 4a and 4b in 43 and 58% yields respectively. The reaction of
bromopyrones 2b and 2c with dimethylsulfide in MeOH: CH2Cl2 afforded the corresponding sulfonium
salts 5b and 5c in 66 and 65% yields respectively. Treatment of 5b and 5c with arene carbaldehydes
such as (Ar ¼ p-ClC6H4, o-ClC6H4, p-NO2C6H4, o-NO2C6H4, p-FC6H4, 2-naphthyl, p-MeOC6H4,
C6H5CH¼¼CH, p-MeC6H4, C6H5 and 4-(4-oxo-6-phenyl-4H-pyran-2-yl)-benzaldehyde 4b) in the pres-
ence of sodium hydroxide in CH3CN:H2O afforded eleven trans-epoxides in 61–93% yields.
J. Heterocyclic Chem., 46, 268 (2009).
INTRODUCTION
of our investigations we have synthesized pyrone sulfo-
nium ylides, arene carbaldehydes 4a, b and correspond-
ing trans-epoxides.Arylpyrones 1a and 1b were prepared
according to the literature in two steps [22]. Bromina-
tion of pyrones 1(a–c) with N-bromosuccinimide (NBS)
produced the corresponding bromopyrones 2(a–c) in 55–
70% yields respectively [23]. The hexaminium salts 3a,
b were synthesized by reaction of bromopyrones 2a, b
with hexamethylenetetramine (HMTA) in dry chloro-
form in 71 and 84% yields respectively. Treatment of
3a and 3b with EtOH:H2O under reflux afforded the
corresponding aldehydes 4a and 4b in 43 and 58%
yields respectively (Scheme 1).
For many years, 4-pyrones have been extensively studied
due to a wide range of applications. They are biologically
active and synthetically useful compounds [1–9]. Among
their various biological properties anti-HIV [10,11] and anti-
cancer effects have aroused considerable attention [12,13].
Furthermore epoxides are useful and important synthetic
precursors and have found divers applications in organic
synthesis [14,15]. There are many reports on the synthesis of
epoxides possessing various heterocyclic moieties [16–18].
However synthesis and reactions of pyrone sulfonium salts
and corresponding ylides with arene carbaldehydes have not
been reported as yet. Thus, we became interested in the syn-
thesis, characterization and evaluation of this category of
compounds.
The structures of all new compounds 3a, b and 4a, b
1
were established on the basis of the FT-IR, H NMR,
13C NMR, mass spectral data and elemental analysis.
The sulfonium salts 5b and 5c were synthesized by
reaction of bromopyrones 2b and 2c with dimethylsul-
fide in MeOH:CH2Cl2 in 66 and 65% yields respectively
RESULTS AND DISCUSSION
We are interested in synthesis and developing the
chemistry of pyrone derivatives [19–21]. In continuation
C
V
2009 HeteroCorporation

March 2009
Synthesis of Pyrone Carbaldehydes, Pyrone Sulfonium Ylides, and Related Epoxides
269
Scheme 3
Scheme 1
with hexamethylenetetramine. Aldehyes 4a, b were syn-
thesized by hydrolysis of hexaminium salts. Mono-epox-
ide derivatives of 4-pyrone have been synthesized by
reaction of arene carbaldehydes with 4-pyrone sulfonium
ylide. Ring opening reactions of epoxides are under
investigation.
(Scheme 2). It can be seen from the experimental sec-
tion that all spectroscopic data (FT-IR, 1H NMR, 13C
NMR) and elemental analysis are in full agreement with
proposed structures.
EXPERIMENTAL
1H NMR and 13C NMR spectra were recorded with a FT-
NMR-Bruker spectrometer at 400 and 100 MHz respectively.
FT-IR spectra were obtained using KBr pellets on tensor 27-
Bruker. Mass spectra were recorded on Finnigan-Mat 8400,
70ev mass spectrometer. Elemental analyses were carried out
on a Heareus CHN-Rapid, and were found to agree favorably
with the calculated values. Thin layer chromatography was
performed using silica gel 60 HF254. Melting points were
recorded on Mel-TEMP 1202D apparatus and are uncorrected.
2-(4-Bromomethylphenyl)-6-methyl-4H-pyran-4-one (2a). A
mixture of 2-methyl-6-(4-methylphenyl)-4H-pyran-4-one 1a
(1g, 5 mmol), NBS (0.91g, 5.12 mmol) and catalytic amount
of benzoyl peroxide in CCl4 (20 mL) was heated at reflux for
48 h. The reaction mixture was cooled to room temperature
and the precipitate was collected by filtration. The solid was
dissolved in CH2Cl2 (40 mL), washed with saturated aqueous
NaHCO3 solution (3 ꢀ 10 mL) and water (2 ꢀ 10 mL) then
dried over MgSO4. The crude product was purified by prepara-
tive layer chromatography (PLC) on silica gel using n-hexa-
ne:acetone (2:1) as eluent to produce the title compound.
White solid, 0.77g (55%), mp 170–172ꢁC; FT-IR(KBr): 3041,
2973, 1660 (pyrone C¼¼O), 1596, 1507, 1389, 1233, 917,
Synthesis of epoxides was the final step of this inves-
tigation. Thus treatment of 2,6-bis-sulfonium salt 5c
with eight arene carbaldehydes produced the bis-epox-
ides in 30–73% yields. Solubility of bis-epoxides in var-
ious solvents was very low; consequently purification
and evaluation of these compounds was very difficult,
time consuming and materials intensive. For these rea-
sons we focused our attention on the synthesis of mono-
epoxides. Thus treatment of mono-sulfonium salt of py-
rone 5b with various arene carbaldehydes resulted in the
formation of mono-epoxides 6(b1-b10) and 7 in 61–93%
yields (Scheme 3).
The structures of the epoxides were established on the
1
basis of FT-IR, H NMR, 13C NMR [24], mass spectral
data and elemental analysis and by comparison with lit-
1
erature H NMR data for epoxide protons [25,26]. In a
similar manner the reaction of sulfonium salt 5b with
aldehyde 4b resulted in the formation of epoxide 7 in
61% yield (Scheme 4).
841cmꢂ1; H NMR (CDCl3): d 2.36 (s, 3H, CH3), 4.50 (s, 2H,
1
CH2), 6.17 (d, 1H, J ¼ 1.1 Hz, vinyl-H), 6.68 (d, 1H, J ¼ 2
Hz, vinyl-H), 7.49 (d, 2H, J ¼ 8 Hz, Ar-H), 7.72 (d, 2H, J ¼
8 Hz, Ar-H) ppm; 13C NMR (CDCl3): d 18.81, 31.14, 109.97,
113.40, 125.13, 128.59, 130.20, 139.94, 161.72, 164.35,
178.98 ppm; ms: m/z (%): 280 and 278 (Mþ, 6 and 6), 199
(40), 171 (100), 115 (56). Anal. Calcd. for C13H11BrO2: C,
55.95; H, 3.94. Found: C, 55.59; H, 3.90.
CONCLUSION
In this study, hexaminium salts of 4-pyrones have
been synthesized by reaction of bromomethylpyrones
Scheme 2
Scheme 4
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

270
A. Shahrisa and M. Saraei
Vol 46
¼ 2 Hz, vinyl-H), 6.90 (d, 1H, J ¼ 2 Hz, vinyl-H), 7.55-7.56
(m, 3H, Ar-H), 7.85-7.87 (m, 2H, Ar-H), 8.04 (s, 4H, Ar-H),
10.11 (s, 1H, aldehyde-H) ppm; 13C NMR (CDCl3): d 110.76,
112.08, 124.98, 125.52, 128.25, 129.26, 130.19, 130.68,
135.74, 136.99, 160.70, 162.69, 178.77, 190.14 ppm; ms: m/z
(%): 276 (Mþ, 85), 247 (100), 220 (48), 189 (44), 165 (35),
129 (23), 105 (17), 102 (29), 77 (25). Anal. Calcd. for
C18H12O3: C, 78.31; H, 4.34. Found: C, 77.95; H, 4.50.
General procedure for the synthesis of sulfonium salts
(5b and 5c). To a stirred solution of 2-(4-bromomethyl-
phenyl)-6-phenyl-4H-pyran-4-one 2b (2 g, 5.865 mmol) in dry
MeOH:CH2Cl2 (2:1) was added dimethylsulfide (1.7 mL,
23.46 mmol) in one portion at 35ꢁC under argon and the mix-
ture was stirred for 72 h. The crude product was purified by
concentration, precipitation in cold acetone (0ꢁC), filtration fol-
lowed by vacuum drying to give 5b.
General procedure for synthesis of hexaminium salts (3a
and 3b). 2-(4-Bromomethylphenyl)-6-methyl-4H-pyran-4-one
2a and 2-(4-bromomethylphenyl)-6-phenyl-4H-pyran-4-one 2b
(5.86 mmol) were dissolved in dry CHCl3 (20 mL). Then a so-
lution of hexamethylenetetramine (5.86 mmol) in CHCl3
(20 mL) was added dropwise to the flask. The mixture was
refluxed for 30 min to complete precipitation. The precipitate
collected by was filtered, and washed with chloroform and
dried in vacuo to give hexaminium salts.
Hexaminium salt (3a). White solid, 2.12 g (71%), FT-IR
(KBr): 3046, 2967, 2899, 1656 (pyrone C¼¼O), 1600, 1511,
1390, 1036, 931, 821 cmꢂ1 1H NMR (D2O): d 2.37 (s, 3H,
;
CH3), 4.18 (s, 2H, CH2), 4.59 and 4.62 (AB system, JAB ¼ 12
Hz, 3 ꢀ CH2), 5.15 (s, 6H, 3 ꢀ CH2), 6.19 (d, 1H, J ¼ 1.5
Hz, vinyl-H), 6.69 (d, 1H, J ¼ 2 Hz, vinyl-H), 7.58 (d, 2H, J
¼ 8 Hz, Ar-H), 7.91 (d, 2H, J ¼ 8 Hz, Ar-H) ppm; 13C NMR
(D2O): d 18.02, 59.08, 68.87, 77.12, 108.77, 111.94, 125.71,
126.69, 131.26, 131.97, 162.78, 168.32, 181.59 ppm. Anal.
Calcd. for C19H23O2N4Br: C, 54.45; H, 5.40; N, 13.36. Found:
C, 54.16; H, 5.50; N, 13.30.
In a similar manner, sulfonium salt 5c was prepared by reac-
tion of 2,6-bis (4-bromomethylphenyl)-4H-pyran-4-one 2c (1g,
30 mmol) and dimethylsulfide (1.4 mL, 18.43 mmol).
Dimethyl[4-(4-oxo-6-phenyl-4H-pyran-2-yl)benzyl] sulfonium-
bromide (5b). White powder, 1.56 g (66%), FT-IR (KBr): 3096,
2988, 2923, 2823, 1644 (pyrone C¼¼O), 1428, 1388, 1016, 850
Hexaminium salt (3b). White solid, 2.30g (84%), FT-IR
(KBr): 3056, 2949, 2893, 1646 (pyrone C¼¼O), 1601, 1500,
1
cmꢂ1; H NMR (DMSO-d6): d 2.87 (s, 6H, 2 ꢀ CH3), 4.82 (s,
1
1457, 1437, 1005, 775 cmꢂ1; H NMR (D2O): d 4.04 (s, 2H,
2H, CH2), 7.04 (d, 1H, J ¼ 2 Hz, Vinyl-H), 7.08 (d, 1H, J ¼ 2
Hz, Vinyl-H), 7.56-7.61 (m, 3H, Ph-H), 7.68 (d, 2H, J ¼ 8 Hz,
Ar-H), 8.17 (d, 2H, J ¼ 8 Hz, Ar-H) ppm; 13C NMR (DMSO-
d6): d 23.88, 44.95, 110.98, 111.49, 126.07, 126.86, 129.23,
130.81, 131.49, 131.60, 131.77, 131.97, 161.55, 162.45, 178.92
ppm. Anal. Calcd. for C20H19 BrO2S: C, 59.59; H, 4.71; S, 7.93.
Found: C, 59.30; H, 4.70; S, 7.71.
CH2), 4.60 and 4.62 (AB system, JAB ¼ 16 Hz, 3 ꢀ CH2),
5.11 (s, 6H, 3 ꢀ CH2), 6.32 (d, 1H, J ¼ 2 Hz, vinyl-H), 6.42
(d, 1H, J ¼ 2 Hz, vinyl-H), 7.26 (d, 2H, J ¼ 8 Hz, Ar-H),
7.38-7.44 (m, 5H, Ar-H), 7.63 (d, 2H, J ¼ 8 Hz, Ar-H) ppm;
13C NMR (DMSO-d6): d 58.38, 69.77, 77.73, 110.98, 111.59,
126.01, 126.57, 128.92, 129.21, 130.77, 131.58, 132.47,
133.25, 161.50, 162.41, 178.87 ppm. Anal. Calcd. for
C24H25O2N4Br: C, 59.91; H, 5.14; N, 11.63. Found: C, 59.60;
H, 5.20; N, 11.25.
2,6-Bis[dimethyl(4-methyphenyl)sulfoniumbromide]-4H-
pyran-4-one (5c). Yellow solid, 0.83 g (65%), FT-IR (KBr):
3046, 2996, 2907, 2826, 1643 (pyrone C¼¼O), 1599, 1505,
1420, 1383, 847cmꢂ1
;
1H NMR (D2O): d 2.85 (s, 12H, 4 ꢀ
4-(6-Methyl-4-oxo-4H-pyran-2-yl)benzaldehyde
(4a). A
solution of hexaminium salt 3a (0.1g, 0.24 mmol) in 10 mL of
EtOH:H2O (3:2) was refluxed for 24 h. The reaction mixture
was cooled and solvent was removed under reduced pressure
and then water was added (5 mL). The reaction mixture was
extracted by ethyl acetate (3 ꢀ 10 mL) and dried over
MgSO4. The solvent was removed under reduced pressure and
crude product was purified by PLC on silica gel using n-hexa-
ne:acetone (2:1) as eluent. White solid, 0.022 g (43%), mp
183–85ꢁC. FT-IR (KBr): 3055, 2960, 2857, 2769, 1698 (alde-
hyde C¼¼O), 1662 (pyrone C¼¼O), 1607, 1391, 1171, 956, 825
CH3), 4.62 (s, 4H, 2 ꢀ CH2), 6.52 (s, 2H, vinyl-H), 7.48 (d,
4H, J ¼ 8 Hz, Ar-H), 7.69 (d, 4H, J ¼ 8 Hz, Ar-H) ppm; 13C
NMR (D2O): d 24.35, 46.38, 110.65, 127.25, 131.30, 131.41,
131.87, 163.46, 182.15 ppm. Anal. Calcd. for C23H26Br2O2S2:
C, 49.49; H, 4.65; S, 11.48. Found: C, 49.47; H, 4.69; S,
11.49.
General procedure for the synthesis of epoxides 6(b1-b10)
and 7. To a solution of sulfonium salt 5b (0.248 mmol) and
aromatic aldehyde or pyronecarbaldehyde 4b (0.248 mmol) in
acetonitrile:water (1:1) was added NaOH powder (0.248
mmol) at r.t and was stirred for 1 h to complete reaction. The
resulting precipitates were filtered off and washed with water
to remove remaining sulfonium salt, then dried in vacuum to
give the epoxide.
cmꢂ1 1H NMR (CDCl3): d 2.41 (s, 3H, CH3), 6.23 (s, 1H,
;
vinyl-H), 6.80 (d, 1H, J ¼ 2 Hz, vinyl-H), 7.93 (d, 2H, J ¼
8.4 Hz, Ar-H), 8.0 (d, 2H, J ¼ 8.4 Hz, Ar-H), 10.09 (s, 1H,
aldehyde-H) ppm; 13C NMR (CDCl3):
d 20.31, 112.86,
115.14, 126.76, 130.53, 136.99, 138.30, 162.25, 166.13,
180.13, 191.64 ppm; ms: m/z (%); 214 (Mþ, 28), 186 (94),
129 (100), 77 (38). Anal. Calcd. for C13H10O3: C, 72.92; H,
4.67. Found: C, 72.80; H, 4.80.
2-{4-[3-(4-Chlorophenyl)oxiranyl]phenyl}-6-phenyl-4H-pyran-
4-one (6b1). White solid, 0.08g (81%), mp 208–210ꢁC, FT-IR
(KBr): 3059, 2990, 1645 (pyrone C¼¼O), 1601, 1394, 1085,
832 cmꢂ1
;
1H NMR (CDCl3): d 3.86 (d, 1H, J ¼ 1.6 Hz,
4-(4-Oxo-6-phenyl-4H-pyran-2-yl)-benzaldehyde (4b). A
solution of hexaminium salt 3b (2g, 14.16 mmol) in 50 mL of
EtOH: H2O (3:2) was refluxed for 24 h. The mixture was
cooled and diluted with water. The precipitate was collected
by filtration, washed with water and dried in vacuo. The crude
product was purified by column chromatography on silica gel
using n-hexane:acetone (2:1) as eluent to give the title com-
pound. White solid, 0.66 g (58%), mp 185–187ꢁC. FT-IR
(KBr): 3062, 2830, 2738, 1697 (aldehyde C¼¼O), 1646 (pyrone
epoxide-H), 3.90 (d, 1H, J ¼ 1.6 Hz, epoxide-H), 6.83 (s, 2H,
vinyl-H), 7.26-7.31 (m, 2H, Ar-H), 7.36-7.39 (m, 2H, Ar-H),
7.49-7.56 (m, 5H, Ar-H), 7.85-7.89 (m, 4H, Ar-H) ppm; 13C
NMR (CDCl3):
d 61.21, 61.42, 110.50, 110.55, 124.94,
125.22, 125.23, 125.84, 127.87, 128.17, 130.42, 130.47,
130.55, 133.42, 134.07, 139.37, 161.79, 162.39, 179.08 ppm;
ms: m/z (%): 402 and 400 (Mþ, 13 and 40), 371 (46), 365
(30), 275 (15), 191 (13), 147 (23), 133 (36), 105 (59), 102
(92), 89 (100), 77 (30), 69 (14). Anal. Calcd. for C25H17ClO3:
C, 74.95; H, 4.24. Found: C, 74.62; H, 4.30.
C¼¼O), 1384, 890 cmꢂ1
;
1H NMR (CDCl3): d 6.85 (d, 1H, J
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DOI 10.1002/jhet

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Synthesis of Pyrone Carbaldehydes, Pyrone Sulfonium Ylides, and Related Epoxides
271
130.39, 132.07, 132.38, 132.91, 139.70, 161.74, 162.24,
178.99 ppm; ms: m/z (%): 416 (Mþ, 3), 387 (8), 155 (21), 40
(68), 139 (100), 105 (55), 102 (38), 91 (79), 77 (52), 69 (8).
Anal. Calcd. for C29H20O3: C, 83.69; H, 4.80. Found: C,
83.30; H, 4.90.
2-{4-[3-(2-Chlorophenyl)oxiranyl]phenyl}-6-phenyl-4H-pyran-
4-one (6b2). White solid, 0.039 g (78%), mp 195–196ꢁC, FT-
IR (KBr): 3039, 2987, 1646 (pyrone C¼¼O), 1604, 1391, 1032,
764 cmꢂ1
;
1H NMR (CDCl3): d 3.83 (d, 1H, J ¼ 1.2 Hz,
epoxide-H), 4.23 (d, 1H, J ¼ 1.2 Hz, epoxide-H), 6.85 (s, 2H,
vinyl-H), 7.26-7.40 (m, 4H, Ar-H), 7.54-7.56 (m, 5H, Ar-H),
7.86-7.91 (m, 4H, Ar-H) ppm; 13C NMR (CDCl3): d 59.35,
60.52, 110.43, 110.48, 124.78, 124.97, 125.27, 125.39, 126.16,
128.19, 128.30, 130.38, 130.51, 132.20, 133.61, 139.43,
161.99, 162.49, 179.15 ppm; ms: m/z (%): 402 and 400 (Mþ,
5 and 14), 371 (7), 105 (73), 102 (100), 89 (97), 77 (39).
Anal. Calcd. for C25H17ClO3: C, 74.95; H, 4.24. Found: C,
74.70; H, 4.30.
2-{4-[3-(4-Methoxyphenyl)oxiranyl]phenyl-6-phenyl-4H-py-
ran-4-one (6b7). White solid, 0.06g (62%), mp 170–171ꢁC,
FT-IR (KBr): 3055, 2955, 1644 (pyrone C¼¼O), 1605, 1511,
1388, 1249, 829 cmꢂ1 1H NMR (CDCl3): d 3.82 (s, 3H,
;
OCH3), 3.83 (d, 1H, J ¼ 1.6 Hz, epoxide-H), 3.92 (d, 1H, J
¼ 1.6 Hz, epoxide-H), 6.81 (s, 2H, vinyl-H), 6.92 (d, 2H, J
¼ 8 Hz, Ar-H), 7.26-7.29 (m, 2H, Ar-H), 7.48-7.55 (m, 5H,
Ar-H), 7.84-7.87 (m, 4H, Ar-H) ppm; 13C NMR (CDCl3): d
54.30, 60.99, 62.02, 110.40, 110.42, 113.07, 124.89, 125.11,
125.15, 125.80, 127.47, 128.13, 130.22, 130.37, 130.42,
139.93, 158.93, 161.85, 162.29, 179.07 ppm; ms: m/z (%):
396 (Mþ, 31), 368 (52), 367 (100), 275 (21), 121 (68), 120
(58), 105 (66), 102 (38), 91 (79), 77 (52), 69 (8). Anal.
Calcd. for C26H20O4: C, 78.84; H, 5.04. Found: C, 78.45; H,
5.20.
2-{4-[3-(4-Nitrophenyl)oxiranyl]phenyl}-6-phenyl-4H-pyran-
4-one (6b3). White solid, 0.09 g (89%), mp 228–230ꢁC, FT-IR
(KBr): 3060, 2985, 1645 (pyrone C¼¼O), 1597, 1514 (N¼¼O),
1442, 1393, 1339 (N¼¼O), 846 cmꢂ1
;
1H NMR (CDCl3): d
3.94 (d, 1H, J ¼ 1.2 Hz, epoxide-H), 4.00 (d, 1H, J ¼ 1.2 Hz,
epoxide-H), 6.82 (s, 2H, vinyl-H), 7.50-7.55 (m, 7H, Ar-H),
7.85-7.91 (m, 4H, Ar-H), 8.26 (d, 2H, J ¼ 8 Hz, Ar-H) ppm;
13C NMR (CDCl3): 60.87, 61.62, 110.49, 110.63, 122.96,
124.95, 125.31, 128.20, 130.34, 130.55, 130.86, 138.65,
142.75, 147.02, 161.69, 162.49, 179.03 ppm. Anal. Calcd. for
C25H17NO5: C, 73.05; H, 4.16; N, 3.40. Found: C, 72.80; H,
4.00; N, 3.40.
2-Phenyl-6-[4-(3-styryloxiranyl)phenyl]-4H-pyran-4-one
(6b8). Yellow solid, 0.069g (71%), mp 97–99ꢁC, FT-IR
(KBr): 3057, 2858, 1650 (pyrone C¼¼O), 1600, 1497, 1447,
1
1395, 884 cmꢂ1; H NMR (CDCl3): d 3.54 (dd, 1H, J ¼ 1.6,
8 Hz, epoxide-H), 3.96 (d, 1H, J ¼ 1.6 Hz, epoxide-H), 6.08
(dd, 1H, J ¼ 8, 16 Hz, vinyl-H), 6.82 (s, 2H, C3- and C5-H),
6.85 (d, 1H, J ¼ 16 Hz, vinyl-H), 7.28-7.56 (m, 10H, Ar-H),
7.85-7.88 (m, 4H, Ar-H) ppm; 13C NMR (CDCl3): d 59.12,
62.44, 110.43, 110.46, 124.52, 124.93, 125.14, 125.20, 125.52,
127.32, 127.70, 128.16, 130.28, 130.40, 130.46, 134.00,
134.79, 139.82, 161.89, 162.37, 179.15 ppm; ms: m/z (%):
392 (Mþ, 4), 364 (6), 363 (100), 276 (12), 275 (33), 248 (23),
147 (30), 133 (34), 130 (33), 116 (53), 115 (100), 105 (57),
102 (39), 77 (30), 69 (21). Anal. Calcd. for C27H20O3: C,
82.67; H, 5.09. Found: C, 82.43; H, 4.14.
2-{4-[3-(2-Nitrophenyl)oxiranyl]phenyl}-6-phenyl-4H-pyran-
4-one (6b4). White solid, 0.094 g (93%), mp 240–241ꢁC, FT-
IR (KBr): 3068, 2855, 1643 (pyrone C¼¼O), 1591, 1520
(N¼¼O), 1399, 1340 (N¼¼O), 852 cmꢂ1
;
1H NMR (CDCl3): d
3.87 (d, 1H, J ¼ 2 Hz, epoxide-H), 4.49 (d, 1H, J ¼ 2 Hz,
epoxide-H), 6.81-6.82 (m, 2H, vinyl-H), 7.51-7.57 (m, 6H, Ar-
H), 7.73-7.74 (m, 2H, Ar-H), 7.84-7.90 (m, 4H, Ar-H), 8.19
(d, 1H, J ¼ 8 Hz, Ar-H) ppm; 13C NMR (CDCl3): d 59.40,
60.37, 110.44, 110.55, 123.77, 124.92, 125.25, 125.53, 126.04,
127.92, 128.14, 130.38, 130.43, 130.66, 132.42, 133.44,
138.87, 146.47, 161.86, 162.35, 179.10 ppm. Anal. Calcd. for
C25H17NO5: C, 73.05; H, 4.13; N, 3.40. Found: C, 72.65; H,
4.00; N 3.40.
2-Phenyl-6-[4-(3-p-tolyloxiranyl)phenyl]-4H-pyran-4-one
(6b9). White solid, 0.075g (80%), mp 203–205ꢁC, FT-IR
(KBr): 3058, 2992, 1641 (pyrone C¼¼O), 1614, 1391, 1021,
2-{4-[3-(4-Fluorophenyl)oxiranyl]-phenyl}-6-phenyl-4H-
pyran-4-one(6b5). White solid, 0.083g (88%), mp 186–
187ꢁC, FT-IR (KBr): 3058, 2984, 1645 (pyrone C¼¼O), 1601,
813 cmꢂ1 1H NMR (CDCl3): d 2.37 (s, 3H, CH3), 3.85 (d,
;
1H, J ¼ 1.6 Hz, epoxide-H), 3.93 (d, 1H, J ¼ 1.6 Hz, epox-
ide-H), 6.82 (s, 2H, vinyl-H), 7.19-7.26 (m, 4H, Ar-H), 7.49-
7.55 (m, 5H, Ar-H), 7.85-7.88 (m, 4H, Ar-H) ppm; 13C NMR
(CDCl3): d 20.22, 61.11, 62.16, 110.47, 110.48, 124.46,
124.93, 125.16, 125.20, 128.16, 128.33, 130.31, 130.43,
130.45, 132.52, 137.50, 139.94, 161.89, 162.35, 179.1 ppm;
ms: m/z (%): 380 (Mþ, 46), 351 (59), 275 (33), 133 (25), 114
(53), 105 (100), 102 (88), 89 (27), 77 (55). Anal. Calcd. for
C26H20O3: C, 82.14; H, 5.26. Found: C, 82.00; H, 5.58.
1
1507, 1447, 1392, 1230, 831 cmꢂ1; H NMR (CDCl3): d 3.87
(d, 1H, J ¼ 1.6 Hz, epoxide-H), 3.91 (d, 1H, J ¼ 1.6 Hz,
epoxide-H), 6.83 (s, 2H, vinyl-H), 7.07-7.11 (m, 2H, Ar-H),
7.32-7.35 (m, 2H, Ar-H), 7.49-7.55 (m, 5H, Ph-H), 7.85-7.89
(m, 4H, Ar-H) ppm; 13C NMR (CDCl3): d 61.18, 61.53,
110.54, 114.59, 114.80, 124.96, 125.23, 126.19, 126.27,
128.19, 130.43, 130.50, 131.28, 131.31, 139.52, 160.69,
161.84, 162.40, 163.15, 179.13 ppm; ms: m/z (%): 384 (Mþ,
16), 355 (17), 147 (13), 108 (85), 105 (67), 102 (100), 77
(36), 69 (18). Anal. Calcd. for C25H17FO3: C, 78.16; H, 4.42.
Found: C, 77.77; H, 4.40.
2-Phenyl-6-[4-(3-phenyloxiranyl)phenyl]-4H-pyran-4-one
(6b10). White solid, 0.075g (83%), mp 197–199ꢁC, FT-IR
(KBr): 3059, 2986, 1645 (pyrone C¼¼O), 1603, 1393,
1
879cmꢂ1; H NMR (CDCl3): d 3.88 (d, 1H, J ¼ 1.6 Hz, epox-
2-[4-(3-Naphthalen-2-yl-oxiranyl)-phenyl]-6-phenyl-4H-4-
one (6b6). White solid, 0.086g (84%), mp 187–189ꢁC, FT-IR
(KBr): 3051, 2976, 1642 (pyrone C¼¼O), 1600, 1503, 1390,
ide-H), 3.93 (d, 1H, J ¼ 1.6 Hz, epoxide-H), 6.81 (s, 2H,
vinyl-H), 7.35-7.39 (m, 5H, Ar-H), 7.49-7.54 (m, 5H, Ar-H),
7.84-7.87 (m, 4H, Ar-H) ppm; 13C NMR (CDCl3): d 61.12,
62.05, 110.65, 110.79, 124.45, 124.87, 125.11, 125.18, 127.53,
127.59, 128.11, 130.31, 130.35, 130.41, 135.47, 139.73,
161.80, 162.29, 179.14 ppm; ms: m/z (%): 366 (Mþ, 75), 337
(5), 195 (16), 191 (32), 133 (22), 130 (31) 105 (100), 102
(100), 89 (81), 77 (56), 69 (15). Anal. Calcd. for C25H18O3: C,
82.01; H, 4.91. Found: C, 81.66; H, 5.00.
1
824 cmꢂ1; H NMR (CDCl3): d 4.05 (d, 1H, J ¼ 1.6, epoxide-
H), 4.06 (d, 1H, J ¼ 1.6, epoxide-H), 6.83 (s, 2H, vinyl-H),
7.42-7.57 (m, 8H, Ar-H), 7.48-7.57 (m, 7H, Ar-H), 7.84-7.90
(m, 8H, Ar-H) ppm; 13C NMR (CDCl3): d 61.21, 62.30,
110.41, 110.42, 121.56, 124.15, 124.86, 125.12, 125.20,
125.26, 125.48, 126.75, 126.77, 127.51, 128.10, 130.35,
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

272
A. Shahrisa and M. Saraei
Vol 46
[9] Bransova, J.; Brtko, J.; Uher, M.; Novotny, L. Int J Bio-
chem Cell Biol 1995, 27, 701.
2,3-Bis[4-(4-oxo-6-phenyl-4H-pyran-2-yl)phenyl]oxirane
(7). Yellow powder, 0.081g (61%), mp 282–284ꢁC, FT-IR
(KBr): 3058, 2963, 1648 (pyrone C¼¼O), 1603, 1501, 1386,
[10] Ishibashi, Y.; Ohba, S.; Nishiyama, S.; Yamamura, S. Tetra-
hedron Lett 1996, 37, 2997.
942, 839cmꢂ1 1H NMR (CDCl3): d 3.97 (s, 2H, epoxide-H),
;
[11] Garey, D.; Ramirez, M.; Gonzales, S.; Wertsching, A.; Tith,
S.; Keefe, K.; Pen˜a, M. R. J Org Chem 1996, 61, 4853.
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38, 7761.
6.83 (s, 4H, vinyl-H), 7.52-7.59 (m, 10H, Ar-H), 7.84-7.91 (m,
8H, Ar-H) ppm; 13C NMR (CDCl3): d 61.46, 110.59, 110.66,
124.94, 125.27, 125.28, 128.19, 130.40, 130.50, 130.69,
139.16, 161.72, 162.40, 179.03 ppm; ms: m/z (%): 536 (Mþ,
17), 508 (40), 264 (73), 248 (73), 234 (73), 191 (73), 189
(73), 105 (70), 102 (53), 77 (63). Anal. Calcd. for C36H24O5:
C, 80.61; H, 4.47. Found: C, 80.68; H, 4.51.
[13] Matsumura, Y.; Shirai, K.; Maki, T.; Itakura, Y.; Kodera,
Y. Tetrahedron Lett 1998, 39, 2339.
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[16] Zanardi, J.; Leriverend, C.; Aubert, D.; Julienne, K.; Metz-
ner, P. J Org Chem 2001, 66, 5620.
Acknowledgment. The authors thank the Research Council of
University of Tabriz for financial support.
`
[17] Miniere, S.; Reboul, V.; Metzner, P.; Fochi, M.; Bonini, B.
F. Tetrahedron Asymmetry 2004, 15, 3275.
[18] Aggarwal, V. K.; Winn, C. L. Acc Chem Res 2004, 37,
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Presented in part in the 40th IUPAC Congress, 14–19 August 2005,
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Journal of Heterocyclic Chemistry
DOI 10.1002/jhet