Waste-Free Solid-State Organic Syntheses
775
(2C), 126.42, 126.77 (2C), 127.52 (2C), 129.32, 130.44,
137.91, 143.12, 144.72, 166.80 ppm.
NH2), 6.75–7.45 (m, Ar0H and pyridine H-5) ppm; 13C
NMR (CDCl3): ꢃ ¼ 20.18, 24.76, 105.90, 112.47, 115.17,
115.66, 118.59, 120.98, 131.48, 137.76, 149.61, 152.23,
161.34, 161.86 ppm; MS: m=z (%) ¼ 255 (88), 222 (100),
136 (24), 80 (28).
2-(p-Methoxybenzylidenehydrazino)-4-phenylthiazole
(8c, C17H15N3OS)
Yield 100%; mp 210–212ꢁC (Ref. [11] 213–217ꢁC; IR (KBr):
ꢂꢀ¼ 3279 (NH), 1626 (C¼N) cmꢂ1
;
1H NMR (CDCl3=
2-(4,6-Dimethyl-3-cyano-2-pyridinylthio)benzenediazonium
nitrate hydrate (12)
CF3COOD): ꢃ ¼ 3.90 (s, OCH3), 7.20–7.90 (m, Ar0H and
thiazole H-5), 8.30 (s, N¼CH) ppm.
Compound 11 (510mg, 2.00mmol) was evacuated in a
250 cm3 flask and then exposed to 360 mg NO2 (7.8mmol)
at 0.7 bar for 6 h at room temperature with occasional careful
shaking. The excess gas was recovered from a trap at 77K.
Yield 100%; mp 106–107ꢁC; IR (KBr): ꢂꢀ¼ 2292 (NꢃN),
2218 (CꢃN) cmꢂ1; 1H NMR (CF3COOD): ꢃ ¼ 2.90 (s, CH3),
3.00 (s, CH3), 7.90 (s, pyridine H-5), 8.20–8.95 (m, Ar0H)
ppm; 13C NMR (CF3COOD): ꢃ ¼ 20.87, 20.98, 109.61,
112.01, 115.29, 119.83, 129.78, 134.42, 135.89, 138.85,
143.81, 152.29, 163.01, 163.72 ppm.
Solid-State Preparation of 2-(Arylidenehydrazino)-4-
antipyrinylthiazoles 9
A mixture of 529 mg 4-chloroacetylantipyrine (2.00 mmol)
and 2.00 mmol 6 was ball-milled at 50ꢁC for 1 h. After
drying at 0.01 bar at 80ꢁC quantitative yields of the hydro-
chloride salts 9 were obtained. The free bases 9 were ob-
tained by washing the fine powder of the hydrochloride with
5% Na2CO3 solution, followed by H2O, and drying at 80ꢁC
in vacuum.
Solid-State Azo-Coupling of 12 with ꢁ-Naphthol
Naphthalene-1,2-dione 1-[2-(40,60-dimethyl-30-cyano-20-
2-(Benzylidenehydrazino)-4-antipyrinylthiazole
(9a, C21H19N5OS)
pyridinylthio)phenyl]hydrazone (13, C24H18N4OS)
Yield 100%; mp 218–219ꢁC; IR (KBr): ꢂꢀ¼ 3437 (NH), 1625
ꢁ-Naphthol (coupler A, 288 mg, 2.00 mmol) was ground in an
agate mortar, and 694mg 12 (3.00 mmol) were added and co-
ground in five portions for 10min each. Most of the diazonium
band at ꢂꢀ¼ 2292 cmꢂ1 disappeared, but the completion of the
reaction was achieved by 24 h ultrasound application in a test
tube. The solid product was neutralized with 20 cm3 0.5 N
NaOH, washed with H2O, and dried. Yield 100%; mp 157–
1
(C¼N) cmꢂ1; H NMR (CDCl3): ꢃ ¼ 2.60 (s, CH3), 3.25 (s,
CH3), 6.90 (s, thiazole H-5), 7.20–7.70 (m, Ar0H), 8.30 (1H, s,
N¼CH), 9.50 (1H, s, NH) ppm; MS: m=z (%) ¼ 389 (100),
286 (35), 243 (28), 103 (50), 77 (36), 56 (58).
2-(p-Methylbenzylidenehydrazino)-4-antipyrinylthiazole
(9b, C22H21N5OS)
1
158ꢁC; IR (KBr): ꢂꢀ¼ 2215 (CꢃN), 1619 (C¼N) cmꢂ1; H
Yield 100%; mp 228–229ꢁC; IR (KBr): ꢂꢀ¼ 3391 (NH), 1609
(C¼N) cmꢂ1; 1H NMR (CDCl3=DMSO-d6): ꢃ ¼ 2.40 (s, CH3),
2.65 (s, CH3), 3.35 (s, CH3), 7.10 (s, thiazole H-5), 7.25–7.70
(m, Ar0H), 8.35 (s, N¼CH), 9.75 (s, NH) ppm; 13C NMR
(CDCl3=DMSO-d6): ꢃ ¼ 10.76, 19.71, 33.11, 96.38, 99.51,
124.11 (2C), 125.68 (2C), 126.39, 127.72 (2C), 127.87
(2C), 128.98, 132.28, 133.58, 139.13, 146.47, 149.25, 161.06,
165.20ppm.
NMR (CDCl3): ꢃ ¼ 2.20 (s, CH3), 2.40 (s, CH3), 6.60–8.45
(m, Ar0H and pyridine H-5), 16.00 (s, NH) ppm; 13C NMR
(CDCl3): ꢃ ¼ 20.21, 24.57, 105.66, 115.06, 116.92, 119.38,
121.06, 121.91, 125.77, 126.16, 126.41, 128.16, 128.66,
128.98, 130.75, 131.32, 133.61, 137.14, 140.87, 146.70,
152.23, 160.24, 161.76, 175.17ppm; MS: m=z (%) ¼ 410
(24), 279 (100), 254 (45), 239 (84), 115 (56).
Solid-State Azo-Coupling of 12 with Acetoacetanilide,
Pyrazolones, and Barbituric Acid
2-(p-Methoxybenzylidenehydrazino)-4-antipyrinylthiazole
(9c, C22H21N5O2S)
Acetoacetanilide (coupler B), 5-methylpyrazol-3-ones
(coupler C), or barbituric acid (coupler D) (2.00 mmol)
and the solid diazonium salt 12 (2.00 mmol) were cau-
tiously co-ground in an agate mortar for 5 min. The mixture
was transferred to a 100 cm3 flask, which was then evacu-
ated. The mixture was exposed to (CH3)3N (0.5 bar) for
12 h at room temperature. After condensation of the gas
into a remote trap at 77 K, the trimethylammonium nitrate
was washed away with 20 cm3 H2O, and the residual solid
was dried.
Yield 100%; mp 226–227ꢁC; IR (KBr): ꢂꢀ¼ 3398 (NH), 1606
(C¼N) cmꢂ1
6.90–7.60 (m, Ar0H), 8.10 (s, N¼CH) ppm.
;
CH3), 3.40 (s, CH3), 3.85 (s, OCH3), 6.70 (s, thiazole H-5),
1H NMR (CDCl3=CF3COOD): ꢃ ¼ 2.50 (s,
2-(2-Aminophenylthio)-3-cyano-4,6-dimethylpyridine
(11, C14H13N3S)
A solution of 1.66 g 2-chloro-4,6-dimethylnicotinonitrile
(10) (10.0 mmol), 1.25 g aminothiophenol (10.0 mmol), and
1.38 g anhydrous K2CO3 in 50 cm3 ethanol was heated un-
der reflux for 2 h. The precipitate which formed on cooling
was filtered off, washed with H2O, dried, and recrystallized
from ethanol. Yield 88%; mp 163–164ꢁC; IR (KBr):
2-[(40,60-Dimethyl-30-cyano-20-pyridinylthio)-2-
phenylhydrazono]-3-oxo-N-phenylbutanamide
(14, C24H21N5O2S)
ꢂꢀ¼ 3411 and 3309 (NH2), 2212 (CꢃN), 1620 (C¼N) cmꢂ1
;
Yield 100%; mp 204–205ꢁC; IR (KBr): ꢂꢀ¼ 3429 (NH), 2220
1H NMR (CDCl3): ꢃ ¼ 2.35 (s, CH3), 2.45 (s, CH3), 4.45 (s,
(CꢃN), 1667 (C¼O) cmꢂ1
;
1H NMR (CDCl3): ꢃ ¼ 2.20