Mar-Apr 2008
Synthesis of Azirines Containing Aldehyde Functionality and their Utilization
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was stirred for 15 min at 10 ºC and then for 5 min at rt (25-30
ºC). Then the reaction mixture was decomposed with water and
the aqueous portion was extracted with DCM. Removal of the
solvent under reduced pressure followed by purification by
preparative TLC [silica gel GF-254, hexane-ethyl acetate (7:1)
as eluent] gave 2-formyl-azirines 3 (60-68 %) and the isoxazoles
4 (6-8 %) as the only isolable products. Bis-2H-azirines 7 were
prepared in a similar manner.
(200 MHz, CDCl3): δ = 2.87 (d, J = 6.4 Hz, 1H, NCH), 7.61 (d,
J = 8.1 Hz, 2H, Ar-H), 7.85 (d, J = 8.2 Hz, 2H, Ar-H), 8.95 (d, J
= 6.7 Hz, 1H, CHO); 13C NMR (50 MHz, CDCl3): δ = 38.92,
122.49, 129.45, 130.51, 134.35, 159.31, 199.86.
2,3-Diphenyl-2H-azirine-2-carbaldehyde 3f. White solid,
mp 99-102 °C (from DCM); IR (KBr) νmax: 1764, 1707, 1599,
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1447, 1232 cm-1; H NMR (200 MHz, CDCl ): δ = 7.17-7.84
3
(m, 2H, Ar-H), 7.63-7.94 (m, 8H, Ar-H), 9.32 (s, 1H, CHO); 13
C
NMR (50 MHz, CDCl3): δ = 127.59, 128.14, 128.30, 128.48,
128.84, 129.32, 129.63, 130.20; 130.68, 133.34, 134.02, 134.41,
141.81, 150.05, 193.85; Mass (ES+): m/z 222.07 (MH +, 100 %).
4,5-Diphenyl-isoxazole 4f. Yellow viscous compound; IR
3-Phenyl-2H-azirine-2-carbaldehyde 3a. Yellow solid; mp
47-50 °C (from ether) (lit mp 49-51 °C) [7]; IR (KBr) νmax 1773,
1710, 1451, 1116 cm-1; 1H NMR (200 MHz, CDCl 3): δ = 2.53 (d,
J = 6.5 Hz, 1H, NCH), 6.75-6.99 (m, 3H, Ar-H), 7.15-7.34 (m,
2H, Ar-H), 8.70 (d, J = 6.4 Hz, 1H, CHO); 13C NMR (50 MHz,
CDCl3): δ = 39.01, 122.49, 129.32, 130.51, 134.35, 159.32,
199.86; Mass (ES+): m/z 146 [MH+, 100%], 117 [M+-CO].
3-Phenyl isoxazole 4a. Pale yellow viscous liquid; IR (KBr)
νmax 3050, 2967, 1670, 1608 cm-1; 1H NMR (200 MHz, CDCl 3):
δ = 6.66 (d, J = 1.7 Hz, 1H, NCCH), 7.42-7.47 (m, 3H, Ar-H),
7.80-7.85 (m, 2H, Ar-H), 8.45 (d, J = 1.7 Hz, 1H, OCH); 13C
NMR (50 MHz, CDCl3): δ = 102.43, 126.89, 128.80, 128.93,
130.02, 158.85, 161.51; Mass (ES+): m/z 146 [MH+, 100%];
HRMS (ES+) calcd for C9H7NO (MH+) 146.0528 found
146.0663.
3-(p-Tolyl)-2H-azirine-2-carbaldehyde 3b. Pale yellow
solid; mp 32-34 °C (from ether) (lit mp 31-32 °C) [8]; IR (KBr)
νmax 1773, 1710, 1451, 1116 cm-1; 1H NMR (200 MHz, CDCl3):
δ = 2.52 (s, 3H, CH3), 2.87 (d, J = 6.7 Hz, 1H, NCH), 7.45- 7.50
(m, 2H, Ar-H), 7.87-8.03 (m, 2H, Ar-H), 8.99 (d, J = 6.6 Hz,
1H, CHO); 13C NMR (50 MHz, CDCl3): δ = 22.02, 39.01,
122.49, 129.32, 130.51, 144.35, 159.32, 199.86; Mass (ES+):
m/z 160.07 [MH+, 100%].
1
(KBr) νmax: 2960, 1610, 1575, 1440 cm-1; H NMR (200 MHz,
CDCl 3) [28]: δ = 7.26-7.42 (m, 6H, Ar-H), 7.75 (d, J = 7.6 Hz,
2H, Ar-H), 7.89 (s, 1H, OCH), 8.04-8.06 (m, 2H, Ar-H); Mass
(ES+): m/z 222 (MH+, 100 %); Elemental analysis calcd for
C15H11NO: C, 81.43; H, 5.01; N, 6.33. Found C, 81.51; H, 5.29;
N, 6.38.
3-Azido-2-methyl-3-phenyl propenal 2g. Pale yellow oil; IR
(KBr) νmax: 2114, 1773, 1701, 1654, 1560, 1508, 1458 cm-1; 1H
NMR (200 MHz, CDCl3): δ = 1.87 (s, 3H, CH3), 7.45-7.87 (m,
3H, Ar-H), 7.26-7.37 (m, 2H, Ar-H), 9.27 (s, 1H, CHO); 13C
NMR (50 MHz, CDCl3): δ = 40.79, 128.40, 128.89, 129.39,
130.14, 156.26, 164.90, 200.38; Mass (ES+): m/z 160 (MH+-N2,
100 %); Elemental analysis calcd for C10H9N3O: C, 64.16; H,
4.85; N, 22.45. Found C, 63.89; H, 4.79; N, 22.38.
2-Methyl-3-phenyl-2H-azirine-2-carbaldehyde 3g. Yellow
1
oil; IR (KBr) νmax: 1760, 1703, 1599, 1440; H NM (200 MHz,
CDCl 3): δ = 1.51 (s, 3H, CH3), 7.55-7.72 (m, 3H, Ar-H), 7.83
(d, J = 1.9 Hz, 1H, Ar-H), 7.87 (d, J = 1.43 Hz, 1H, Ar-H), 8.84
(s, 1H, CHO); Elemental analysis calcd for C10H9NO: C, 75.45;
H, 5.70; N, 8.80. Found C, 75.53; H, 4.81; N, 9.02.
Bis-4,4'-[ 3-(2H-azirine-2-formyl)]phenylmethane 7a. Pale
yellow solid mp 89-91 °C (from DCM); IR (KBr) νmax: 1738,
1618 cm-1; 1H NMR (200 MHz, CDCl3): δ = 2.87 (d, J = 6.4 Hz,
2H, NCH), 4.21 (s, 2H, CCH2C), 7.44 (d, J = 8.1 Hz, 4H, Ar-H),
7.88 (d, J = 8.1 Hz, 4H, Ar-H), 8.95 (d, J = 6.4 Hz, 2H, CHO);
13C NMR (50 MHz, CDCl3): δ = 29.67, 38.95, 42.19, 129.34,
130.63, 146.70, 158.93, 200.00; DEPT-135: 38.95 (CH2), 42.18
(NCH); Mass (FAB): m/z 303 [M++H, 40%]; HRMS (ES+) calcd
for C19H14N2O2 (MH+) 303.1056 found 303.1113.
3-(p-Tolyl)isoxazole 4b. Colorless solid; mp 53-55 °C (from
DCM) (Lit. 55-56 °C) [27]; IR (KBr): 3030, 2921, 1612, 1557,
1
1520, 1121 cm-1; H NMR (200 MHz, CDCl3): δ = 2.30 (s, 3H,
CH3), 6.63 (d, J = 1.6 Hz, 1H, NCCH), 7.28 (d, J = 8.1 Hz, 2H, Ar-
H), 7.76 (d, J = 8.1 Hz, 2H, Ar-H), 8.43 (d, J = 1.6 Hz, 1H, OCH).
3-Naphthalen-2-yl-2H-azirine-2-carbaldehyde 3c. Yellow
solid, mp 60-62 °C (from DCM); IR (KBr) νmax: 1771, 1706,
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1279, 1110, 819 cm-1; H NMR (200 MHz, CDCl3) [12]: δ =
2.89 (d, J = 2.7 Hz, 1H, NCH), 7.53-7.63 (m, 3H, Ar-H), 7.86-
7.97 (m, 4H, Ar-H) 8.92 (d, J = 6.7 Hz, 1H, CHO); 13C NMR
(50 MHz, CDCl3): δ = 26.63, 123.86, 126.73, 127.74, 128.40,
129.51, 130.14, 132.49, 134.48, 135.56, 198.06; Mass (ES+):
m/z 196[MH+, 100%], 167[M+-CO]; HRMS (ES+) calcd for
C13H9NO (MH+) 196.0684 found 196.0785.
Bis-4,4'-(3-isoxazole)phenylmethane 8a. Pale yellow
1
semisolid; (KBr) νmax 3010, 1601, 1556 cm-1; H NMR (200
MHz, CDCl 3): δ = 4.07 (s, 2H, CCH2C), 6.62 (d, J = 1.5 Hz,
2H, NCCH), 7.28 (d, J = 10.3 Hz, 4H, Ar-H), 7.75 (d, J = 10.3
Hz, 4H, Ar-H), 8.43 (d, J = 1.5 Hz, 2H, OCH); 13C NMR (50
MHz, CDCl3): δ = 39.02, 119.17, 130.07, 157.89, 159.78; Mass
(ES+): m/z 303 (MH+); Elemental analysis calcd for C19H14N2O2:
C, 75.48; H, 4.67; N, 9.27. Found C, 75.55; H, 4.68; N 9.19.
Bis-4,4'-[ 3-(2H-azirine-2-formyl)]phenylether 7b. Yellow
solid, mp 93-95 °C (from DCM); IR (KBr) νmax: 1706, 1592,
3-Naphthalen-2-yl-isoxazole 4c. Yellow viscous liquid; IR
1
(KBr) νmax 3040, 2968, 1611, 1561cm-1; H NMR (200 MHz,
CDCl3): δ = 6.80 (d, J = 1.5 Hz, 1H, NCCH), 7.51-7.59 (m, 2H,
Ar-H), 7.87-7.97 (m, 4H, Ar-H), 8.27 (s, 1H, Ar-H), 8.50 (d, J =
1.5 Hz, 1H, OCH),; Mass (ES+): m/z 196 [MH+, 100%];
Elemental analysis calcd for C13H9NO: C, 80.07; H, 4.65; N,
7.18. Found C, 79.92; H, 4.70; N, 7.2.
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1494, 1244 cm-1; H NMR (200 MHz, CDCl 3): δ = 2.90 (d, J =
3-(p-chlorophenyl)-2H-azirine-2-carboxaldehyde 3d. Pale
yellow solid, mp 87-90 °C (from ether) (lit mp 88-89 °C) [8]; IR
6.2 Hz, 2H, NCH), 7.25-7.30 (m, 4H, Ar-H) , 7.92-7.97 (m, 4H,
Ar-H), 8.98 (d, J = 6.3 Hz, 2H, CHO); 13C NMR (50 MHz,
CDCl3): δ = 30.67, 43.19, 128.34, 132.63, 150.70, 156.93,
198.00; Mass (ES+): m/z 305 (MH+); HRMS (ES+) calcd for
C18H12N2O3 (MH+) 305.0848 found 305.0921.
1
(KBr) νmax: 1770, 1710, 1680, 1125, 990 cm-1; H NMR (200
MHz, CDCl3): δ = 2.87 (d, J = 6.4 Hz, 1H, NCH), 7.63 (d, J =
8.0 Hz, 2H, Ar-H), 7.86 (d, J = 8.1 Hz, 2H, Ar-H), 8.95 (d, J =
6.7 Hz, 1H, CHO); 13C NMR (50 MHz, CDCl3): δ = 38.92,
122.49, 129.45, 130.51, 139.35, 159.31, 199.86.
3-(p-bromophenyl)-2H-azirine-2-carboxaldehyde 3e. Pale
yellow solid, mp 107-109 °C (from ether) (lit mp 109-110 °C)
[8]; IR (KBr) νmax: 1773, 1715, 1690, 1119, 988 cm-1; 1H NMR
Bis-4,4'-(3-isoxazole)phenylether 8b. Yellow viscous liquid;
IR (KBr) νmax 3035, 1620, 1560 cm-1; 1H NMR (200 MHz, CDCl
3): δ = 6.66 (d, J = 1.5 Hz, 2H, NCCH), 7.12-7.22 (m, 4H, Ar-
H), 7.86-7.95 (m, 4H, Ar-H), 8.48 (d, J = 1.8 Hz, 2H, OCH); 13
C
NMR (50 MHz, CDCl3): δ = 120.07, 132.07, 158.29, 160.70,;