B. Abarca et al. / Tetrahedron 64 (2008) 3794e3801
3799
3:1) affording 3-methyl-6-(p-tolylsulfinyl)-[1,2,3]triazolo[1,5-
3.11. 3-Methyl-4-(p-tolylsulfinyl)-[1,2,3]triazolo[1,5-a]-
pyridine (18)
a]pyridine (15) as a yellow solid, 213 mg, 32%. Mp 152e
154 ꢁC. HRMS found for Mþ 271.0778; C14H13N3OS requires
271.0779. 1H NMR (300 MHz, CDCl3) d¼9.05 (d, J¼1.37 Hz,
1H), 7.59 (m, 3H), 7.31 (d, J¼8.3 Hz, 2H), 7.06 (dd, J¼9.26,
1.37 Hz, 1H), 2.58 (s, 3H), 2.39 (s, 3H). 13C NMR (75.5 MHz,
CDCl3) d¼142.9 (C), 140.1 (C), 137.3 (C), 133.3 (C), 132.1
(C), 130.4 (CH), 125.0 (CH), 123.4 (CH), 119.1 (CH), 118.6
(CH), 21.5 (CH3), 10.3 (CH3). EM (EI) m/z (%) 271 (26),
243 (27), 226 (30), 195 (64), 139 (100), 123 (62), 91 (40),
65 (50) and 3-methyl-6-(p-tolylthio)-[1,2,3]triazolo[1,5-a]pyr-
idine (21) as a yellow solid, 198 mg, 31%. Mp 87e90 ꢁC.
HRMS found for Mþ 255.0833; C14H13N3S requires
Starting material 4-bromo-3-methyl-[1,2,3]triazolo[1,5-a]-
pyridine (10) (100 mg, 0.5 mmol). The crude product was
purified by flash chromatography (silica, ethyl acetate/cyclo-
hexane, 1:4/2:1) affording 3-methyl-4-(p-tolylsulfinyl)-
[1,2,3]triazolo[1,5-a]pyridine (18) as a yellow solid, 107 mg,
80%. Mp 157e160 ꢁC. HRMS found for Mþ 271.0786;
C14H13N3OS requires 271.0779. 1H NMR (300 MHz,
CDCl3) d¼8.70 (d, J¼7.0 Hz, 1H), 7.90 (d, J¼7.0 Hz, 1H),
7.50 (d, J¼8.1 Hz, 2H), 7.27 (d, J¼8.1 Hz, 2H), 7.10 (t,
J¼7.0 Hz, 1H), 2.60 (s, 3H), 2.38 (s, 3H). 13C NMR
(75.5 MHz, CDCl3) d¼143.3 (C), 140.2 (C), 137.3 (C),
134.4 (C), 133.5 (C), 132.0 (C), 130.5 (CH), 127.3 (CH),
126.6 (CH), 122.2 (CH), 114.1 (CH), 21.5 (CH3), 13.1
(CH3). EM (EI) m/z (%) 271 (0.5), 243 (83), 228 (32), 226
(49), 200 (100), 123 (7) and 3-methyl-4-(p-tolylthio)-
[1,2,3]triazolo[1,5-a]pyridine (23), traces. HRMS found for
Mþ 255.0832; C14H13N3S requires 255.0830. 1H NMR
(300 MHz, CDCl3) d¼8.39 (d, J¼6.9 Hz, 1H), 7.30 (d,
J¼8.0 Hz, 2H), 7.18 (d, J¼8.0 Hz, 2H), 6.66 (t, J¼7.0 Hz,
1H), 6.55 (d, J¼7.0 Hz, 1H), 2.78 (s, 3H), 2.36 (s, 3H). 13C
NMR (75.5 MHz, CDCl3) d¼139.2 (C), 136.9 (C), 135.6
(C), 133.9 (C), 133.2 (CH), 130.6 (CH), 127.1 (C), 122.4
(CH), 118.3 (CH), 114.8 (CH), 21.1 (CH3), 12.8 (CH3). EM
(EI) m/z (%) 255 (15), 227 (27), 226 (95), 212 (100), 194 (32).
1
255.0830. H NMR (300 MHz, CDCl3) d¼8.36 (br s, 1H),
7.44 (dd, J¼9.1, 0.9 Hz, 1H), 7.32 (d, J¼8.1 Hz, 2H), 7.15
(d, J¼8.1 Hz, 2H), 7.00 (dd, J¼9.1, 1.4 Hz, 1H), 2.54 (s,
3H), 2.33 (s, 3H). 13C NMR (75.5 MHz, CDCl3) d¼139.0
(C), 134.7 (C), 132.8 (CH), 130.5 (CH), 130.2 (C), 128.5
(C), 126.6 (C), 126.3 (CH), 123.7 (CH), 117.0 (CH), 21.1
(CH3), 10.3 (CH3). EM (EI) m/z (%) 255 (10), 227 (100),
226 (67), 123 (15), 91 (25), 65 (20).
3.9. 6-(p-Tolylthio)-[1,2,3]triazolo[1,5-a]pyridine (22)
Prepared from 6-bromo-[1,2,3]triazolo[1,5-a]pyridine (6b)
(99 mg, 0.5 mmol). The crude product was purified by
chromatotron (silica, ethyl acetate/cyclohexane gradient) af-
fording 6-(p-tolylthio)-[1,2,3]triazolo[1,5-a]pyridine (22) as
a yellow solid, 40 mg, 36%. Mp 80e83 ꢁC. HRMS found
3.12. 3-(p-Tolylsulfinyl)-[1,2,3]triazolo[1,5-a]pyridine (19)
1
for Mþ 241.0680; C13H11N3S requires 241.0674. H NMR
3-Iodo-[1,2,3]triazolo[1,5-a]pyridine (4) (0.43 mmol) was
used. The crude product was purified by chromatotron (silica,
ethyl acetate/cyclohexane) affording 5-(p-tolylsulfinyl)-
[1,2,3]triazolo[1,5-a]pyridine (19) as a yellow solid, 25 mg,
20%. Mp 119e123 ꢁC. HRMS found for Mþ 257.0622;
C13H11N3OS requires 257.0623. 1H NMR (300 MHz,
CDCl3) d¼8.77 (d, J¼7.0 Hz, 1H), 7.80 (d, J¼8.9 Hz, 1H),
7.69 (d, J¼8.1 Hz, 2H), 7.33 (m, 3H), 7.09 (dt, J¼7.0,
1.1 Hz, 1H), 2.39 (s, 3H). 13C NMR (75.5 MHz, CDCl3)
d¼141.6 (C), 139.9 (C), 133.3 (C), 132.4 (C), 130.0 (CH),
127.8 (CH), 125.9 (CH), 124.5 (CH), 118.2 (CH), 116.5
(CH), 21.4 (CH3). EM (EI) m/z (%) 257 (2), 229 (13), 213
(21), 212 (100), 181 (83), 180 (51), 91 (12), 78 (21).
(300 MHz, CDCl3) d¼8.48 (s, 1H), 8.00 (s, 1H), 7.60 (d,
J¼9.2 Hz, 1H), 7.38 (d, J¼8.1 Hz, 2H), 7.21 (d, J¼8.0 Hz,
2H), 7.12 (d, J¼9.2 Hz, 1H), 2.38 (s, 3H). 13C NMR
(75.5 MHz, CDCl3) d¼139.3 (C), 133.1 (CH), 132.2 (C),
130.7 (CH), 128.1 (C), 127.7 (CH), 127.3 (C), 125.8 (CH),
123.4 (CH), 117.4 (CH), 21.2 (CH3). EM (EI) m/z (%) 243
(3), 241 (57), 213 (100), 212 (58), 198 (20), 171 (21), 123
(15), 91 (10).
3.10. 5-(p-Tolylsulfinyl)-[1,2,3]triazolo[1,5-a]pyridine (17)
Starting material 5-bromo-[1,2,3]triazolo[1,5-a]pyridine
(6a) (100 mg, 0.5 mmol). The crude product was purified by
chromatotron (silica, ethyl acetate/cyclohexane, 1:4/2:1) af-
fording 5-(p-tolylsulfinyl)-[1,2,3]triazolo[1,5-a]pyridine (17)
as a yellow solid, 108 mg, 84%. Mp 134e135 ꢁC. HRMS
3.13. 1-[6-(p-Tolylsulfinyl)pyridin-2-yl]ethanol (25)
7-(p-Tolylsulfinyl)-3-methyl-[1,2,3]triazolo[1,5-a]pyridine
(14) (0.1 g, 0.4 mmol, 1.0 equiv) was diluted in an aqueous so-
lution of sulfuric acid (10 mL, 2.5 M) and heated to 100 ꢁC.
The reaction was monitored by TLC. Upon completion of
the reaction (6 h) the reaction mixture was quenched with
saturated aqueous solution of NaHCO3 (11 mL) until pH¼8.
Then the resulting mixture was extracted with dichloromethane
(3ꢂ50 mL). The organic extracts were combined, washed with
brine (20 mL), dried over Na2SO4, filtered and concentrated.
Column chromatography (silica gel, ethyl acetate/cyclohexane
gradient) provided 1-(6-(p-tolylsulfinyl)pyridin-2-yl)ethanol
1
found for Mþ 257.0622; C13H11N3OS requires 257.0623. H
NMR (300 MHz, CDCl3) d¼8.67 (d, J¼7.3 Hz, 1H), 8.23
(m, 1H), 8.18 (d, J¼0.95 Hz, 1H), 7.56 (d, J¼8.0 Hz, 2H),
7.3 (d, J¼8.0 Hz, 2H), 6.88 (dd, J¼7.3, 1.7 Hz, 1H), 2.38 (s,
3H). 13C NMR (75.5 MHz, CDCl3) d¼144.1 (C), 143.1 (C),
140.3 (C), 132.8 (C), 130.5 (CH), 127.3 (CH), 126.0 (CH),
125.2 (CH), 114.8 (CH), 110.2 (CH), 21.44 (CH3). EM (EI)
m/z (%) 259 (4), 257 (89), 229 (3), 181 (70), 139 (15), 123
(45), 90 (100).