8308 J . Org. Chem., Vol. 63, No. 23, 1998
Cho et al.
mL of THF at -78 °C. The solution was stirred for 10 min.
To this solution was added 30 mL of MeOH, which was cooled
below -30 °C. The precipitated product was filtered and
washed with cold methanol. The deuterated compounds 1a a ′-
d 1, 1a c′-d 1, 1a d ′-d 1, and 1ea ′-d 1 were prepared by the same
procedure using the thiophene-2-carboxaldehyde-d1 and 4-ni-
trothiophene-2-carboxaldehyde-d1, respectively.16-19 In most
cases, the products were analytically pure and used without
further purification. The spectral and analytical data of the
compounds were consistent with the proposed structures. The
yield (%), melting point (°C), IR (KBr, CdO, cm-1), NMR
(CDCl3), and combustion analysis data for the new compounds
are as follows (all J values are in Hz).
(Z)-C4H3(S)CHdNOC(O)C6H5 (1a a ′): yield 50%; mp 68-
70 °C; IR 1744; NMR δ 8.32-8.25 (m, 2H), 8.16 (s, 1H), 7.76-
7.62 (m, 2H), 7.58-7.48 (m, 3H), 7.21-7.16 (m, 1H). Anal.
Calcd for C12H9NO2S: C, 62.32; H, 3.92; N, 6.06; S, 13.86.
Found: C, 62.44; H, 4.10; N, 6.12; S, 13.90.
(Z)-C4H3(S)CDdNOC(O)C6H5 (1a a -d 1): yield 65%; mp 68-
70 °C; IR 2239 (C-D), 1742; NMR δ 8.32-8.26 (m, 2H), 7.76-
7.60 (m, 2H), 7.58-7.48 (m, 3H), 7.20-7.16 (m, 1H). Anal.
Calcd for C12H8DNO2S: C, 62.05; H, 4.34; N, 6.03; S, 13.80.
Found: C, 62.30; H, 4.15; N, 5.92; S, 13.59.
(Z)-C4H3(S)CHdNOC(O)C6H4-m -Br (1a b′): yield 52%; mp
94-95 °C; IR 1757; NMR δ 8.42 (s, 1H), 8.22 (d, 1H, J ) 8.0),
8.17 (s, 1H), 7.81-7.75 (m, 2H), 7.55 (d, 1H, J ) 4.0), 7.43 (t,
1H, J ) 8.0), 7.21 (t, 1H, J ) 4.0). Anal. Calcd for C12H8-
NO2SBr: C, 46.47; H, 2.60; N, 4.52; S, 10.34. Found: C, 46.57;
H, 2.69; N, 4.52; S, 10.20.
(Z)-C4H3(S)CHdNOC(O)C6H4-m -Br (1a b′-d 1): yield 42%;
mp 94-95 °C; IR 2235 (C-D), 1759; NMR δ 8.43 (s, 1H), 8.22
(d, 1H, J ) 8.0), 7.80-7.75 (m, 2H), 7.56 (d, 1H, J ) 4.0), 7.43
(t, 1H, J ) 8.0), 7.21 (t, 1H, J ) 4.0). Anal. Calcd for C12H7-
DNO2SBr: C, 46.32; H, 2.92; N, 4.50; S, 10.32. Found: C,
46.56; H, 2.65; N, 4.41; S, 10.32.
(Z)-C4H3(S)CHdNOC(O)C6H4-p-NO2 (1a c′): yield 62%; mp
146-147 °C; IR 1749; NMR δ 8.46 (d, 2H, J ) 8.4), 8.40 (d,
2H, J ) 8.4), 8.20 (s, 1H), 7.78 (d, 1H, J ) 4.2), 7.58 (d, 1H, J
) 4.2), 7.22 (t, 1H, J ) 4.2). Anal. Calcd for C12H8N2O4S: C,
52.17; H, 2.92; N, 10.14; S, 11.60. Found: C, 51.87; H, 3.03;
N, 10.16; S, 11.88.
(Z)-C4H3(S)CDdNOC(O)C6H4-p-NO2 (1a c′-d 1): yield 79%;
mp 147-148 °C; IR 2239 (C-D), 1759; NMR δ 8.44 (d, 2H, J
) 8.4), 8.38 (d, 2H, J ) 8.4), 7.79 (d, 1H, J ) 4.2), 7.58 (d, 1H,
J ) 4.2), 7.22 (t, 1H, J ) 4.2). Anal. Calcd for C12H7DN2O4S:
C, 51.98; H, 2.65; N, 10.10; S, 11.56. Found: C, 52.02; H, 2.98;
N, 10.07; S, 11.47.
(Z)-5-O2NC4H2(S)CHdNOC(O)C6H4-p-NO2 (1ec′): yield
50%; mp 134-135 °C; IR 1757; NMR δ 8.45 (d, 2H, J ) 8.0),
8.38 (d, 2H, J ) 8.0), 8.23 (s, 1H), 7.99 (d, 1H, J ) 4.2), 7.49
(d, 1H, J ) 4.2). Anal. Calcd for C12H7N3O6S: C, 44.86; H,
2.20; N, 13.08; S, 9.98. Found: C, 45.12; H, 2.14; N, 13.09; S,
9.63.
(Z)-Furan-2-carbaldehyde oximes were prepared by reflux-
ing a solution of the substituted furan-2-carbaldehyde (20
mmol) and an excess amount of NH2OH in MeOH by the
literature procedure.20-25 All of the (Z)-furan-2-carbaldehyde
O-benzoyloximes were synthesized by the same procedure as
employed for the synthesis of (Z)-thiophene-2-carbaldehyde
O-benzoyloximes except that the reaction temperature was
lowered to -50 °C. The products were obtained as white or
yellow solids. The deuterated compounds 2ba ′-d 1, 2bc′-d 1,
2bd ′-d 1, and 2ea ′-d 1 were prepared by the same procedure
from the 5-methylfuran-2-carbaldehyde-d1 and 5-nitrofuran-
2-carbaldehyde-d1, respectively.16-19 The spectral and analyti-
cal data of the compounds were consistent with the proposed
structures. The yield (%), melting point (°C), IR(KBr, CdO,
cm-1), NMR (CDCl3), and combustion analysis data for the new
compounds are as follows.
(Z)-5-MeC4H2(O)CHdNOC(O)C6H5 (2ba ′): yield 50%; mp
77-78 °C; IR 1794; NMR δ 8.16 (d, 2H, J ) 7.3), 7.82 (s, 1H),
7.62-7.50(m, 3H), 7.21(d, 1H, J ) 3.0), 6.23 (d, 1H, J ) 3.0),
2.39 (s, 3H). Anal. Calcd for C13H11NO3: C, 68.11; H, 4.84;
N, 6.11. Found: C, 68.44; H, 4.50; N, 6.12.
(Z)-5-MeC4H2(O)CDdNOC(O)C6H5 (2ba ′-d 1): yield 55%;
mp 77-78 °C; IR 2239 (C-D), 1793; NMR δ 8.19 (d, 2H, J )
7.3), 7.68-7.45 (m, 3H), 7.21 (d, 1H, J ) 3.0), 6.23 (d, 1H, J )
3.0), 2.43 (s, 3H). Anal. Calcd for C13H10DNO3: C, 67.82; H,
5.25; N, 6.08. Found: C, 67.47; H, 4.95; N, 5.87.
(Z)-5-MeC4H2(O)CHdNOC(O)C6H4-m-Br (2bb′): yield 51%;
mp 99 °C; IR 1747; NMR δ 8.36 (s, 1H), 8.11 (d, 1H, J ) 5.4),
7.78 (s, 1H), 7.75 (d, 1H, J ) 5.4), 7.40 (t, 1H, J ) 5.4), 7.11
(d, 1H, J ) 2.0), 6.23 (d, 1H J ) 2.0), 2.49 (s, 3H). Anal. Calcd
for C13H10BrNO3: C, 50.67; H, 3.27; N, 4.55. Found: C, 50.57;
H, 3.59; N, 4.52.
(Z)-5-MeC4H2(O)CDdNOC(O)C6H4-m -Br (2bb′-d 1): yield
41%; mp 99 °C; IR 2236 (C-D), 1748; NMR δ 8.36 (s, 1H),
8.11 (d, 1H, J ) 5.4), 7.75 (d, 1H, J ) 5.4), 7.40 (t, 1H, J )
5.4), 7.11 (d, 1H, J ) 2.0), 6.24 (d, 1H J ) 2.0), 2.49 (s, 3H).
(Z)-5-MeC4H2(O)CHdNOC(O)C6H4-p-NO2 (2bc′): yield
21%; mp 135-136 °C; IR 1748; NMR δ 8.44-8.32 (m, 4H), 7.84
(s, 1H), 7.13 (d, 1H, J ) 3.0), 6.27 (d, 1H, J ) 3.0), 2.44 (s,
3H). Anal. Calcd for C13H10N2O5: C, 56.94; H, 3.68; N, 10.22.
Found: C, 56.87; H, 3.53; N, 10.16.
(Z)-5-MeC4H2(O)CHdNOC(O)C6H4-p-NO2 (2bc′-d 1): yield
53%; mp 135 °C; IR 2239 (C-D), 1748; NMR δ 8.45-8.29 (m,
4H), 7.17 (d, 1H, J ) 3.0), 6.25 (d, 1H, J ) 3.0), 2.42 (s, 3H).
(Z)-5-MeOC4H2(O)CHdNOC(O)C6H5 (2ca ′): yield 25%;
mp 81-82 °C; IR 1736; NMR δ 8.16 (d, 2H, J ) 7.2), 7.70 (s,
1H), 7.64-7.48 (m, 3H), 7.24 (d, 1H, J ) 3.6), 5.46 (d, 1H, J )
3.6), 3.90 (s, 3H).
(Z)-5-Br C4H2(O)CHdNOC(O)C6H5 (2d a ′): yield 40%; mp
97-98 °C; IR 1757; NMR δ 8.44-8.32 (m, 4H), 7.84 (s, 1H),
7.13 (d, 1H, J ) 3.0), 6.27 (d, 1H, J ) 3.0), 2.44 (s, 3H). Anal.
Calcd for C12H8BrNO3: C, 48.91; H, 2.93; N, 4.75. Found: C,
49.29; H, 2.93; N, 4.57.
(Z)-5-O2NC4H2(O)CHdNOC(O)C6H5 (2ea ′): yield 51%; mp
110-111 °C; IR 1752; NMR δ 8.22 (d, 2H, J ) 7.2), 7.80 (s,
1H), 7.70-7.52 (m, 3H), 7.43 (d, 1H, J ) 3.6), 7.38 (d, 1H, J )
3.6). Anal. Calcd for C12H8N2O5: C, 55.38; H, 3.10; N, 10.77.
Found: C, 55.56; H, 3.09; N, 10.60.
(Z)-5-O2NC4H2(O)CDdNOC(O)C6H5 (2ea ′-d 1): yield 45%;
mp 111-113 °C; IR 2239 (C-D), 1752; NMR δ 8.23 (d, 2H, J
) 7.2), 7.70-7.50 (m, 3H), 7.43 (d, 1H, J ) 3.6), 7.39 (d, 1H,
J ) 3.6).
(Z)-5-MeOC4H2(S)CHdNOC(O)C6H5 (1ca ′): yield 61%; mp
89-91 °C; IR 1736; NMR δ 8.25 (d, 2H, J ) 8.0), 7.93 (s, 1H),
7.69-7.50 (m, 3H), 7.24 (d, 1H, J ) 4.0), 6.30 (d, 1H, J ) 4.0),
3.99 (s, 3H). Anal. Calcd for C13H11NO2S: C, 59.76; H, 4.24;
N, 5.36; S, 12.27. Found: C, 59.61; H, 4.36; N, 5.35; S, 12.00.
(Z)-5-Br C4H2(S)CHdNOC(O)C6H5 (1d a ′): yield 40%; mp
83-85 °C; IR 1757; NMR δ 8.25 (d, 2H, J ) 8.0), 8.04 (s, 1H),
7.72-7.53 (m, 3H), 7.29 (d, 1H, J ) 4.0), 7.17 (d, 1H, J ) 4.0).
Anal. Calcd for C12H8NO2SBr: C, 46.47; H, 2.60; N, 4.52; S,
10.34. Found: C, 46.37; H, 2.65; N, 4.46; S, 10.14.
(Z)-5-O2NC4H2(S)CHdNOC(O)C6H5 (1ea ′): yield 51%; mp
105-107 °C; IR 1752; NMR δ 8.24 (d, 2H, J ) 8.0), 8.18 (s,
1H), 7.97 (d, 1H, J ) 4.2), 7.75-7.56 (m, 3H), 7.45 (d, 1H, J )
4.2). Anal. Calcd for C12H8N2O4S: C, 52.17; H, 2.92; N, 10.14;
S, 11.60. Found: C, 52.21; H, 3.04; N, 10.25; S, 11.57.
(Z)-5-O2NC4H2(S)CHdNOC(O)C6H5 (1ea ′-d 1): yield 79%;
mp 106-107 °C; IR 2258 (C-D), 1751; NMR δ 8.24 (d, 2H, J
) 8.0), 8.18 (s, 1H), 7.97 (d, 1H, J ) 4.2), 7.75-7.56 (m, 3H),
7.45 (d, 1H, J ) 4.2). Anal. Calcd for C12H8N2O4S: C, 52.17;
H, 2.92; N, 10.14; S, 11.60. Found: C, 52.21; H, 3.04; N, 10.25;
S, 11.57.
(Z)-5-O2NC4H2(S)CHdNOC(O)C6H4-m -Br (1eb′): yield
56%; mp 123-125 °C; IR 1751; NMR δ 8.40 (s, 1H), 8.19 (s,
1H), 8.18 (d, 1H, J ) 8.0), 7.97 (d, 1H, J ) 4.2), 7.84 (d, 1H, J
) 8.0), 7.49 (t, 1H, J ) 8.0), 7.47 (d, 1H, J ) 4.2). Anal. Calcd
for C12H7N2O4SBr: C, 40.58; H, 1.99; N, 7.89; S, 9.03. Found:
C, 40.51; H, 1.96; N, 7.77; S, 8.89.
(Z)-5-O2NC4H2(O)CHdNOC(O)C6H4-m -Br (2eb′): yield
30%; mp 123-125 °C; IR 1747; NMR δ 8.33 (s, 1H), 8.20 (d,
1H, J ) 8.0), 7.97 (s, 1H), 7.83 (d, 1H, J ) 7.4), 7.51-7.47 (m,
1H), 7.46 (d, 1H, J ) 3.8), 7.31 (d, 1H, J ) 3.8). Anal. Calcd
for C12H7BrN2O5: C, 42.50; H, 2.08; N, 8.26. Found: C, 42.51;
H, 2.10; N, 8.31.