ORDER
REPRINTS
Synthesis of 20-Acetamido-m-terphenyls
1817
(3.02 g, 10 mmol) in CH2Cl2 (120 mL) containing pyridine (0.80 g, 10 mmol)
was added a solution of thionyl chloride (1.69 g, 10 mmol) in CH2Cl2 (30 mL).
The reaction mixture was stirred at rt for 12 hr and evaporated to dryness to
give a pale yellow residue, which was used as such for the next step. The resi-
due was dissolved in benzene (50 mL) and stirred with aq. ammonia (30 mL)
at rt for 6 hr. The pale yellow solid was filtered and dissolved with CH2Cl2
(100 mL). The organic layer was then washed with water (2 ꢀ 100 mL),
brine (150 mL), dried, and evaporated to give 5 (2.53 g, 84%) as colorless
1
solid. M.P. 2468C; IR: 1683 (C55O) cm21; H NMR: d 2.37 (s, 6H), 5.26
(s, 1H), 5.37 (s, 1H), 7.18-7.45 (m, 11H); 13C NMR: d 21.40, 128.82,
129.22, 129.26, 129.32, 135.06, 137.49, 137.74, 140.12, 171.43; MS (m/z):
301 (M þ, 42), 257 (100), 166 (23), 91 (12); Anal. Calcd. for C21H19NO:
C, 83.69; H, 6.35; N, 4.65. Found: C, 83.71; H, 6.31; N, 4.57.
3-Methyl-7-p-tolyl-(5H)-phenanthridin-6-one (7). (a) From 5: To a solu-
tion of 5 (0.3g, 1 mmol) in benzene (20mL) was added NaOH (5mL, 50%)
and bromine (0.5mL) at 08C. The reaction mixture was stirred for 6 hr, diluted
with water and extracted using CH2Cl2 (2 ꢀ 25mL). The organic layer was
washed with water (2 ꢀ 25mL), brine (25 mL) and dried. The residue obtained
after evaporation of the organic layer was purified by the column chromato-
graphy using EtOAc/hexane (1 : 4) to give 7 (0.19 g 63%) as colorless solid.
1
M.P. 2088C; H NMR: d 2.40 (s, 3H), 2.45 (s, 3H), 6.02 (bs, 1H), 6.92–7.22
(m, 10H); 13C NMR: d 22.44, 22.72, 126.29, 126.48, 127.85, 128.91, 129.08,
129.42, 130.13, 130.37, 131.44, 132.07, 134.82, 134.92, 135.07, 136.84,
138.64, 152.63, 172.04; MS (m/z): 299 (Mþ, 100), 284 (31), 273 (91), 271
(90), 257 (52), 241 (24), 180 (13), 127 (18), 91 (11); Anal. Calcd. for
C21H17NO: C, 84.25; H, 5.72; N, 4.68. Found: C, 84.19; H, 5.62; N, 4.57. (b)
From 5: To a solution of the acid chloride 4 (2.08 g, 6.5 mmol) in dry acetone
(60 mL) was added sodium azide (0.5g, 7.6 mmol) and stirred at rt for 8 hr.
The solvent was evaporated, the residue was dissolved in benzene (30 mL),
refluxed for 6 hr and evaporated. The residue was purified on silica gel using
EtOAc/hexane (1 : 4) to afford 7 (1.43 g 74%) as colorless solid.
20-Acetamido-4,400-dimethyl-1, 10 : 30,100-terphenyl (12). A stirred mix-
ture of 2,6-dichloroacetanilide (0.20 g, 1 mmol), Pd(PPh3)4 (0.01 g) in toluene
(10 mL) was treated with the p-tolylboronic acid (0.30 g, 2.2 mmol) in EtOH
(2 mL) and aq. Na2CO3 (2 mL, 2 M). The resulting mixture was stirred at rt for
8 hr and then evaporated to dryness in vacuo. The residue obtained was then
extracted with CH2Cl2 (2 ꢀ 25 mL), washed with water (2 ꢀ 25 mL) and
dried, evaporated to give a residue, which was purified by column chromato-
graphy (SiO2) elution with EtOAc/hexane (1 : 3) gave 12 (0.10 g, 31%) as pale
yellow solid. M.P.: 1728C; IR (cm21): 3219, 2391, 1664, 1573, 1519, 1290,
1
1016, 783, 424: H NMR (CDCl3): d 2.17 (s, 3H); 2.42 (s, 6H); 7.15–7.33
(m, 11H).