Syn- and Anti-Eliminations Forming Nitriles
J . Org. Chem., Vol. 63, No. 14, 1998 4689
) 9.0), 9.05 (s, 1H). Anal. Calcd for C15H12N2O5: C, 60.00;
H, 4.03; N, 9.33. Found: C, 60.00; H, 4.11; N, 9.24.
(E)-p-O2NC6H4CHdNOC(O)C6H4-m -Br (1d c′): yield 44%;
mp 183-185 °C; IR 1764; NMR δ 7.56 (t, 1H, J ) 8.0), 7.92-
8.19 (m, 4H), 8.19 (s, 1H), 8.35 (d, 2H, J ) 7.0), 9.13 (s, 1H).
Anal. Calcd for C14H9BrN2O4: C, 48.16; H, 2.60; N, 8.02.
Found: C, 48.30; H, 2.64; N, 7.94.
(E)-p-O2NC6H4HdNOC(O)C6H4-p-NO2 (1d d ′): yield 58%;
mp 191-193 °C; IR 1742; NMR δ 8.09 (d, 2H, J ) 9.2), 8.30
(d, 2H, J ) 9.0), 8.38 (d, 2H, J ) 9.2), 8.42 (d, 2H, J ) 9.0),
9.16 (s, 1H). Anal. Calcd for C14H9N3O6: C, 53.34; H, 2.88;
N, 13.33. Found: C, 53.50; H, 2.90; N, 13.22.
(Z)-Benzaldehyde O-benzoyloxime derivatives were synthe-
sized by the following procedures. The deuterated compounds
2a b′-d ′-d1 and 2d a ′-d1 were prepared by using benzaldehyde-
d1 and p-nitrobenzaldehyde-d1 by the same procedure.1,3-5
However, compounds 2ba ′, 2bb′, and 2d d ′were too unstable
to isolate from the reaction mixture.
(i) P r oced u r e A. (Z)-Benzaldoximes (5.0 mmol) were
slowly added to a solution containing substituted benzoyl
chloride (1.7 mmol) in 5.0 mL of pyridine at -35 to -40 °C.
The solution was stirred for 1-30 min. To this solution were
added 20 mL of -10 °C methanol and 50 mL of ice-water.
The solid products were dissolved in the minimum amount of
CH2Cl2 and recrystallized by adding 5 mL of MeOH-15 mL
of H2O at -10 to -15 °C. Compounds 2a a ′, 2ba ′, 2ca ′, 2d a ′,
2bc′, 2bd ′, and 2a a ′-d1 were obtained in reasonable yields by
this procedure. Compounds 2d a ′-d1, 2cb′, and 2d b′ were
synthesized by the same procedure except that 2d ,a ′-d1 was
recrystallyzed three times by adding 5 mL of H2O to the
methanolic solution of the product, and 2cb′ and 2d b′ were
crystallized from 10 mL of benzene-30 mL of hexane at -10
to -15 °C, respectively.
(ii) P r oced u r e B. (Z)-Benzaldoximes (0.66 mmol) and
pyridine (0.05 g, 0.06 mmol) were slowly added to a solution
containing substituted benzoyl chloride (0.90 mmol) in 5.0 mL
of THF at -78 °C. The solution was stirred for 5-10 min. To
this solution was added 30 mL of -10 °C methanol and 50
mL of ice-water. The solid product was filtered while it was
cold and recrystallized from 10 mL of MeOH/H2O ) 3/1 at -10
to -15 °C. Compounds 2a c′, 2cc′, 2d c′, 2a d ′, 2cd ′, 2a c′-d1,
and 2a d ′-d1 were prepared by this procedure. 2d d ′ was
prepared by the same procedure except that the product was
recrystallyzed from MeOH at -15 °C.
Anal. Calcd for C14H9DN2O4: C, 62.00; H, 4.08; N, 10.33.
Found: C, 62.07 ; H, 3.83; N, 10.28.
(Z)-p-MeOC6H4CHdNOC(O)C6H5 (2ba ′): yield 43%; mp
56-58 °C; IR 1741; NMR δ 3.87 (s, 3H), 7.00 (d, 2H, J ) 8.8),
7.46-7.53 (m, 2H), 7.61 (t, 1H, J ) 7.4), 7.80 (s, 1H), 7.90 (d,
2H, J ) 8.8), 8.12 (d, 2H, J ) 7.8). Anal. Calcd for C15H13
-
NO3: C, 70.58; H, 5.13; N, 5.49. Found: C, 70.56; H, 5.14; N,
5.57.
(Z)-p-MeOC6H4CHdNOC(O)C6H4-m-Br (2bc′): yield 39%;
mp 84-85 °C; IR 1759; NMR δ 3.89 (s, 3H), 7.02 (d, 2H, J )
8.8), 7.40 (t, 1H, J ) 7.8), 7.75 (d, 1H, J )7.8), 7.81 (s, 1H),
7.83 (d, 2H, J ) 8.8), 8.04 (d, 1H, J ) 7.8), 8.26 (s, 1H). Anal.
Calcd for C15H12BrNO3: C, 53.91; H, 3.62; N, 4.19. Found:
C, 53.94; H, 3.59; N, 3.92.
(Z)-p-MeOC6H4CHdNOC(O)C6H4-p-NO2 (2bd′): yield 25%;
mp 118-119 °C (dec); IR 1758; NMR δ 3.90 (s, 3H), 7.02 (d,
2H, J ) 9.0), 7.85 (d, 2H, J ) 9.0), 7.85 (s, 1H), 8.28 (d, 2H, J
) 8.8), 8.38 (d, 2H, J ) 8.8). Anal. Calcd for C15H12N2O5: C,
60.00; H, 4.03; N, 9.33. Found: C, 60.04; H, 3.85; N, 9.25.
(Z)-m -Br C6H4CHdNOC(O)C6H5 (2ca ′): yield 30%; mp
78-80°C; IR 1749; NMR δ 7.41-7.75 (m, 6H), 7.88 (s, 1H),
8.07-8.16 (m, 3H). Anal. Calcd for C14H10BrNO2: C, 55.29;
H, 3.31; N, 4.61. Found: C, 55.29; H, 3.36; N, 4.42.
(Z)-m-Br C6H4CHdNOC(O)C6H4-p-OMe (2cb′): yield 42%;
mp 86-88 °C; IR 1746; NMR δ 3.90 (s, 3H), 7.00 (d, 2H, J )
8.7), 7.41 (t, 1H, J ) 7.8), 7.66 (d, 1H, J ) 7.8), 7.76 (d, 1H, J
) 7.8), 7.86 (s, 1H), 8.06 (d, 2H, J ) 8.7), 8.15 (s, 1H). Anal.
Calcd for C15H12BrNO3: C, 53.91; H, 3.62; N, 4.19. Found:
C, 53.87; H, 3.63; N, 4.14.
(Z)-m -Br C6H4CHdNOC(O)C6H4-m -Br (2cc′): yield 52.6%;
mp 86.5-88.5 °C; IR 1758; NMR δ 7.31-7.38 (m, 2H), 7.61-
7.71 (m, 3H), 7.83 (s, 1H), 7.96 (d, 1H, J ) 7.9), 8.08 (s, 1H),
8.16 (s, 1H). Anal. Calcd for C14H9Br2NO2: C, 43.9; H, 2.37;
N, 3.66. Found: C, 43.94; H, 2.28; N, 3.45.
(Z)-m -Br C6H4HdNOC(O)C6H4-p-NO2 (2cd ′): yield 48%;
mp 125-127 °C (dec); IR 1758; NMR δ 7.43 (t, 1H, J ) 7.6),
7.71 (d, 2H, J ) 7.6), 7.94 (s, 1H), 8.11 (s, 1H), 8.26 (d, 2H, J
) 8.4), 8.41 (d, 2H, J ) 8.4). Anal. Calcd for C14H9BrN2O4:
C, 48.16; H, 2.60; N, 8.02. Found: C, 48.33; H, 2.75; N, 7.80.
(Z)-p-O2NC6H4HdNOC(O)C6H5 (2d a ′): yield 55%; mp 96-
98 °C; IR 1758; NMR δ 7.52 (dd, 2H, J ) 7.6, 8.7), 7.65 (t, 1H,
J ) 7.6), 8.05 (d, 4H, J ) 8.7), 8.07 (s, 1H), 8.39 (d, 2H, J )
8.8). Anal. Calcd for C14H10N2O4: C, 62.22; H, 3.73; N, 10.37.
Found: C, 62.24; H, 3.77; N, 10.13.
(Z)-p-O2NC6H4CDdNOC(O)C6H5 (2d a ′-d 1): yield 11%; mp
102-104 °C; IR 1760; NMR δ 7.51 (dd, 2H, J ) 7.5, 8.7), 7.66
(t, 1H, J ) 7.5), 8.05 (d, 4H, J ) 8.7), 8.39 (d, 2H, J ) 8.7).
Anal. Calcd for C14H9DN2O4: C, 62.00; H, 4.08; N, 10.33.
Found: C, 62.30; H, 4.05; N, 10.00.
(Z)-p-O2NC6H4CHdNOC(O)C6H4-p-OMe (2db′): yield 40%;
mp 115-117 °C; IR 1762; NMR δ 3.90 (s, 3H), 7.00 (d, 2H, J
) 9.0), 8.01 (d , 2H, J ) 9.0), 8.04 (s, 1H), 8.05 (d, 2H, J )
8.8), 8.39 (d, 2H, J ) 8.8). Anal. Calcd for C15H12N2O5: C,
60.00; H, 4.03; N, 9.33. Found: C, 60.00; H, 4.03; N, 9.16.
(Z)-p-O2NC6H4CHdNOC(O)C6H4-m -Br (2d c′): yield 48%;
mp 104-106 °C; IR 1756; NMR δ 7.34 (dd, 1H, J ) 7.5, 8.1),
7.72 (d, 1H, J ) 8.1), 7.89 (d, 1H, J ) 7.5), 7.82 (d, 2H, J )
8.5), 8.02 (s, 1H), 8.12 (s, 1H), 8.34 (d, 2H, J ) 8.5). Anal.
Calcd for C14H9BrN2O4: C, 48.16; H, 2.60; N, 8.02. Found:
C, 48.35; H, 2.82; N, 7.83.
1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) was redistilled in
vacuo prior to use, and acetonitrile has been purified as
described before.1 Solutions of DBU in MeCN were prepared
by dissolving DBU in MeCN.
Kin etic Stu d ies. Reactions of (E)-benzaldehyde O-ben-
zoyloximes with DBU in MeCN were followed by monitoring
the decrease in the absorption of the reactants at 260-292
nm with a UV-vis spectrophotometer or a stopped-flow spec-
trophotometer as described before.1 On the other hand,
reactions of 1a a ′-c′, 1ba ′-c′, and their deuterated analogs
with DBU were too slow to measure the infinity absorption
values accurately. Therefore, a Guggenheim method was
employed.
The yield (%), melting point (°C), IR (KBr, CdO, cm-1), NMR
(CDCl3), and combustion analysis data for the new compounds
are as follows.
(Z)-C6H5CHdNOC(O)C6H5 (2a a ′): yield 36%; mp 57-58
°C; IR 1742; NMR δ 7.47-7.68 (m, 7H), 7.87-7.92 (m, 2H),
8.08-8.18 (m, 2H). Anal. Calcd for C14H11NO2: C, 74.65; H,
4.92; N, 6.22. Found: C, 74.68; H, 4.95; N, 6.16.
(Z)-C6H5CDdNOC(O)C6H5 (2a a ′-d 1): yield 47%; mp 55-
57 °C; IR 1741; NMR δ 7.47-7.64 (m, 6H), 7.88-7.93 (m, 2H),
8.09-8.13 (m, 2H). Anal. Calcd for C14H10DNO2: C, 74.32;
H, 5.35; N, 6.19. Found: C, 74.43; H, 5.04; N, 5.83.
(Z)-C6H5CHdNOC(O)C6H4-m -Br (2a c′): yield 35%; mp
71-73 °C; IR 1767; NMR δ 7.33 (dd, 1H, J ) 7.8, 8.1), 7.47-
7.49 (m, 3H), 7.70 (d, 1H, J ) 7.8), 7.79-7.82 (m, 2H), 7.88 (s,
1H), 7.96 (d, 1H, J ) 8.1), 8.18 (s, 1H). Anal. Calcd for C14H10
-
BrNO2: C, 55.29; H, 3.31; N, 4.61. Found: C, 55.46; H, 3.45;
N, 4.18.
(Z)-C6H5CDdNOC(O)C6H4-m -Br (2a c′-d 1): yield 16%; mp
72-74 °C; IR 1766; NMR δ 7.33 (dd, 1H, J ) 7.8, 8.1), 7.43-
7.52 (m, 3H), 7.70 (d, 1H, J ) 7.8), 7.78-7.85 (m, 2H), 7.96 (d,
1H, J ) 8.1), 8.18 (s, 1H). Anal. Calcd for C14H9DBrNO2: C,
55.10; H, 3.63; N, 4.59. Found: C, 55.21; H, 3.32; N, 4.34.
(Z)-C6H5CHdNOC(O)C6H4-p-NO2 (2a d ′): yield 45%; mp
119-120 °C (dec); IR 1752; NMR δ 7.50-7.60 (m, 3H), 7.82-
7.86 (m, 2H), 7.98 (s, 1H), 8.26 (d, 2H, J ) 8.7), 8.37 (d, 2H, J
) 8.7). Anal. Calcd for C14H10N2O4: C, 62.22; H, 3.73; N,
10.37. Found: C, 62.23; H, 3.74; N, 10.26.
(Z)-C6H5CDdNOC(O)C6H4-p-NO2 (2a d ′-d 1): yield 51%;
mp 121-123 °C (dec); IR 1752; NMR δ 7.50-7.58 (m, 3H),
7.82-7.88 (m, 2H), 8.26 (d, 2H, J ) 9.0), 8.37 (d, 2H, J ) 9.0).
P r od u ct Stu d ies. The yields of PhCtN from the reactions
of 1a a ′ and 2a a ′ with DBU were determined by GC as