8302 J . Org. Chem., Vol. 63, No. 23, 1998
Miura et al.
brine and dried (MgSO4). Evaporation, column chromatogra-
phy on silica gel with 9:1 ethyl acetate-EtOH, and crystal-
lization (hexane-benzene) gave 11 in 42% yield (1.36 g, 4.20
mmol) as light brown prisms with mp 142-143 °C: IR (KBr)
addition, the mixture was stirred for 2 h at 0 °C, filtered,
evaporated, and column chromatographed on alumina with
benzene. Recrystallization from hexane-benzene gave 6 in
52% yield (0.88 g, 2.08 mmol) as colorless prisms with mp 120-
122 °C: IR (KBr) 3150 cm-1 (NH); 1H NMR (CDCl3) δ 5.62 (s,
1H), 6.84 (d, J ) 8.3 Hz, 1H), 7.05 (dd, J ) 8.3 and 2.0 Hz,
1H), 7.10 (d, J ) 2.0 Hz, 1H), 7.33-7.39 (m, 10 H), 8.27 (s, 2
H). Anal. Calcd for C23H16Cl2N2S: C, 65.25; H, 3.81; N, 6.62.
Found: C, 65.63; H, 4.20; N, 6.25.
Isola tion of Ra d ica ls. To a stirred solution of 200 mg of
4 or 5 in 20 mL (4a and 4b) or 40 mL (5a and 5b) of benzene
was added 2.0 g of K2CO3. PbO2 (7.00 g for 3a and 3b, and
8.0 g for 5a and 5b) was then added in 6-8 portions during 2
min, and stirring was continued for additional 1 min. After
filtration, the solvent was removed by freeze-drying, and the
greenish crystalline residue was crystallized from hexanes-
ethyl acetate (1a , 1b, 2b) or EtOH (2a ).
N -[(4-Nit r op h e n yl)t h io]-2,6-d ip h e n yl-4-(3-p yr id yl)-
p h en yla m in yl (1a ): dark green fine prisms; yield 19%; mp
170-171 °C. Anal. Calcd for C29H20N3O2S: C, 73.40; H, 4.25;
N, 8.85. Found: C, 73.27; H, 4.14; N, 8.81.
N-[(2,4-Dich lor oph en yl)th io]-2,6-diph en yl-4-(3-pyr idyl)-
p h en yla m in yl (1b): dark green needles; yield 25%; mp 135-
137 °C. Anal. Calcd for C29H19Cl2N2S: C, 69.88; H, 3.84; N,
5.62. Found: C, 69.59; H, 3.92; N, 5.55.
1
3380 and 3300 cm-1 (NH2); H NMR (CDCl3) δ 3.83 (s, 2H),
7.41 (s, 2H), 7.30 (t, J ) 7.3 Hz, 1H), 7.39-7.44 (m, 4H), 7.58
(d, J ) 7.3 Hz, 2H), 7.90 (dt, J ) 8.30 and 2.0 Hz, 2H), 8.65
(dd, J ) 4.9 and 2.0 Hz, 2H), 8.81 (d, J ) 2.0 Hz, 2H). Anal.
Calcd for C22H17N3: C, 81.71; H, 5.30; N, 12.99. Found: C,
81.90; H, 5.70; N, 12.90.
N -[(4-Nit r op h e n yl)t h io]-4-p h e n yl-2,6-d i(3-p yr id yl)-
a n ilin e (5a ). To a stirred solution of 0.97 g (3.00 mmol) of
11 and 2.0 mL of Et3N in 80 mL of anhydrous THF at 0 °C
was added dropwise a solution of 6.0 mmol of 4-nitroben-
zenesulfenyl chloride in 20 mL of anhydrous THF. After the
completion of addition, the mixture was stirred for 2 h at 0
°C, filtered, evaporated, and column chromatographed on
alumina with 1:2 ethyl acetate-benzene. Crystallization from
hexane-benzene gave 5a in 68% yield (0.972 g, 2.04 mmol)
as yellow prisms with mp 186-188 °C: IR (KBr) 3220 cm-1
(NH); 1H NMR (CDCl3) δ 5.19 (s, 1H), 6.93 (d, J ) 8.8 Hz,
2H), 7.24 (dd, J ) 8.5 and 4.9 Hz, 2H), 7.35 (t, J ) 7.3 Hz,
1H), 7.43 (t, J ) 7.3 Hz, 2H), 7.47 (s, 2H), 7.59 (d, J ) 7.3 Hz,
2H), 7.76 (dt, J ) 8.5 and 2.0 Hz, 2H), 7.95 (d, J ) 8.8 Hz,
2H), 8.50 (dd, J ) 4.9 and 2.0 Hz, 2H), 8.72 (d, J ) 2.0 Hz,
2H). Anal. Calcd for C28H20N4O2S: C, 70.57; H, 4.23; N, 11.76.
Found: C, 70.76; H, 4.45; N, 11.49.
N-[(2,4-Dich lor op h en yl)th io]-4-p h en yl-2,6-d i(3-p yr id -
yl)a n ilin e (5b). To a stirred solution of 0.97 g (3.00 mmol)
of 11 and 2.0 mL of Et3N in 80 mL of anhydrous THF at 0 °C
was added dropwise a solution of 6.0 mmol of 2,4-dichloroben-
zenesulfenyl chloride in 10 mL of anhydrous THF. After the
completion of addition, the mixture was stirred for 2 h at 0
°C, filtered, evaporated, and column chromatographed on
alumina with 1:1 ethyl acetate-benzene. Recrystallization
from hexane-benzene gave 5b in 74% yield (1.11 g, 2.22 mmol)
as colorless prisms with mp 179-180 °C: IR (KBr) 3200 cm-1
(NH); 1H NMR (CDCl3) δ 5.12 (s, 1H), 6.91 (d, J ) 8.3 Hz,
1H), 7.03 (dd, J ) 8.3 and 2.0 Hz, 1H), 7.12 (d, J ) 2.0 Hz,
1H), 7.26 (dd, J ) 7.8 and 4.6 Hz, 2H), 7.34(t, J ) 7.3 Hz,
1H), 7.43 (t, J ) 7.3 Hz, 2H), 7.45 (s, 2H), 7.58 (d, J ) 7.3 Hz,
2H), 7.73 (dt, J ) 7.8 and 2.0 Hz, 2H), 8.53 (dd, J ) 4.6 and
N -[(4-Nit r op h e n yl)t h io]-4-p h e n yl-2,6-d i(3-p yr id yl)-
p h en yla m in yl (2a ): dark green fine plates; yield 38%; mp
156-158 °C. Anal. Calcd for C28H19N4O2S: C, 70.72; H, 4.03;
N, 11.78. Found: C, 70.54; H, 4.07; N, 11.60.
N-[(2,4-Dich lor oph en yl)th io]-4-ph en yl-2,6-di(3-pyr idyl)-
p h en yla m in yl (2b): dark green fine needles; yield 31%; mp
125-127 °C. Anal. Calcd for C28H18Cl2N3S: C, 67.34; H, 3.63;
N, 8.41. Found: C, 67.42; H, 3.78; N, 8.22.
2,6-Di(p h en yl-d 5)-4-(3-p yr id yl)a n ilin e. A mixture of 1.97
g (6.00 mmol) of 8, 1.83 g (14.4 mmol) of phenylboronic-d5 acid,
1.39 g (1.20 mmol) of Pd(PPh3)4, and 5.09 g of Na2CO3 in
benzene (83)-EtOH (15)-H2O (24 mL) was refluxed for 24 h
with stirring under nitrogen. The usual workup and subse-
quent column chromatography (1:5 ethyl acetate-benzene)
and crystallization (MeOH) gave 2,6-di(phenyl-d5)-4-(3-pyrid-
yl)aniline as colorless plates with mp 126-128 °C in 45% yield
(0.90 g, 2.7 mmol): IR (KBr) 3440 and 3300 (NH2), 2280 cm-1
(C-D); 1H NMR (CDCl3) δ 4.00 (s, 2 H), 7.31 (dd, J ) 7.8 and
4.9 Hz, 1 H), 7.39 (s, 2 H), 7.88 (dt, J ) 7.8 and 2.0 Hz, 1 H),
8.51 (dd, J ) 4.9 and 2.0 Hz, 1 H), 8.86 (d, J ) 2.0 Hz, 1 H).
Anal. Calcd for C23H8D10N2: C, 83.10; H + D, 5.46; N, 8.43.
Found: C, 82.78; H + D, 5.59; N, 8.00.
N-[(2,4-Dich lor op h en yl)th io]-2,6-d i(p h en yl-d 5)-4-(3-p y-
r id yl)a n ilin e (16). To a stirred solution of 0.66 g (1.99 mmol)
of 2,6-di(phenyl-d5)-4-(3-pyridyl)aniline and 1.0 mL of Et3N in
65 mL of anhydrous THF at 0 °C was added dropwise a
solution of 2.99 mmol of 2,4-dichlorobenzenesulfenyl chloride
in 10 mL of anhydrous THF. After being stirred at 0 °C for 2
h, the reaction mixture was filtered, evaporated, and column
chromatographed on alumina with benzene. Crystallization
from EtOH gave 16 as colorless prisms with mp 139-141 °C
in 65% yield (0.66 g, 1.29 mmol): IR (KBr) 3340 (NH), 2270
cm-1 (C-D); 1H NMR (CDCl3) δ 5.33 (s, 1 H), 6.90 (d, J ) 8.8
Hz, 1 H), 6.97 (dd, J ) 8.8 and 2.0 Hz, 1 H), 7.07 (d, J ) 2.0
Hz, 1 H), 7.33 (dd, J ) 7.8 and 4.9 Hz, 1 H), 7.42 (s, 2 H), 7.87
(dt, J ) 7.8 and 2.0 Hz, 1 H), 8.55 (dd, J ) 4.9 and 2.0 Hz, 1
2.0 Hz, 2H), 8.67 (d, J ) 2.0 Hz, 2H). Anal. Calcd for C28H19
-
Cl2N3S: C, 67.20; H, 3.83; N, 8.40. Found: C, 67.44; H, 4.03;
N, 8.18.
4-Am in o-3,5-d ibr om op yr id in e (12). To a stirred solution
of 9.4 g (100 mmol) of 4-aminopyridine in 40 mL of acetic acid
at 80 °C was added a solution of 34 g (210 mmol) of Br2 in 20
mL of acetic acid over 1 h. After being stirred for 14 h at the
same temperature, the reaction mixture was washed with
aqueous Na2S2O3 and neutralized with 10% NaOH. The
mixture was then extracted with CH2Cl2, and the extract was
washed with brine and dried (MgSO4). Evaporation, chroma-
tography on alumina with 1:1 benzene-ethyl acetate, and
crystallization (hexane-benzene) gave 12 as colorless needles
in 14% yield (3.53 g, 14.0 mmol): IR (KBr) 3430 and 3265 cm-1
1
(NH2); H NMR (CDCl3) δ 5.08 (s, 2H), 8.31 (s, 2H).
4-Am in o-3,5-d ip h en ylp yr id in e (13). A mixture of 3.02
g (12.0 mmol) of 12, 3.80 g (31.0 mmol) of phenylboronic acid,
1.66 g (1.44 mmol) of Pd(PPh3)4, and 10.2 g of Na2CO3 in
benzene (150)-EtOH (30)-H2O (50 mL) was refluxed for 24
h with stirring under nitrogen. After benzene was added, the
organic layer was washed with brine and dried (MgSO4).
Evaporation, column chromatography on silica gel with ethyl
acetate, and crystallization (hexane-benzene) gave 13 in 52%
yield (1.54 g, 6.24 mmol) as colorless prisms with mp 150-
151 °C: IR (KBr) 3480 and 3310 cm-1 (NH2); 1H NMR (CDCl3)
δ 4.48 (s, 2H), 7.43-7.53 (m, 10 H), 8.17 (s, 2 H). Anal. Calcd
for C17H14N2: C, 82.90; H, 5.73; N, 11.37. Found: C, 83.09;
H, 5.79; N, 11.09.
H), 8.85 (d, J ) 2.0 Hz, 1 H). Anal. Calcd for C29H10
-
Cl2D10N2S: C, 68.37; H + D, 3.96; N, 5.50. Found: C, 68.24;
H + D, 4.22; N, 5.27.
4-(P h en yl-d 5)a n ilin e. A mixture of 5.16 g (30.0 mmol) of
4-bromoaniline, 4.95 (39.0 mmol) of phenylboronic-d5 acid, 3.47
g (3.00 mmol) of Pd(PPh3)4, and 12.7 g of Na2CO3 in benzene
(170)-EtOH (30)-H2O (60 mL) was gently refluxed for 24 h
with stirring under nitrogen. The usual workup and subse-
quent crystallization (EtOH) gave 4-(phenyl-d5)aniline in 82%
yield (4.28 g, 24.6 mmol) as colorless plates with mp 54-56
°C: IR (KBr) 3430, 3400, 3330, and 3200 (NH2), 2280 and 2270
cm-1 (C-D); 1H NMR (CDCl3) δ 6.75 (d, J ) 8.3 Hz, 2 H), 7.41
(d, J ) 8.3 Hz, 2H).
N-[(2,4-Dich lor op h en yl)th io]-2,6-d ip h en yl(4-p yr id yl)-
a m in e (6). To a stirred solution of 0.99 g (4.00 mmol) of 13
and 2.0 mL of Et3N in 50 mL of anhydrous THF was added
dropwise a solution of 6.0 mmol of 2,4-dichlorobenzenesulfenyl
chloride in 10 mL of anhydrous THF. After the completion of