532
W.-Y. Liu et al. / Spectrochimica Acta Part A 76 (2010) 531–536
Fig. 1. Synthesis of 1-ferrocenyl-2-(3-substituted-1H-1,2,4-triazol-5-ylthio)ethanone.
TOF6510 spectrograph (Agilent). UV–vis spectra were recorded on
a U-4100 (Hitachi). Fluorescent measurements were recorded on a
2.4.2. 1-Ferrocenyl-2-(3-(furan-2-yl)-1H-1,2,4-triazol-5-
ylthio)ethanone (5b)
Orange solid, yield 73%; mp 139–142 ◦C; IR (KBr, cm−1): 3245,
1662; 1H NMR(CDCl3, 400 MHz), ı: 11.73 (s, 1H, NH triazole), 7.52
(s, 1H, furan), 7.01 (d, J = 3.3 Hz, 1H, furan), 6.51 (t, J = 1.4 Hz, 1H,
furan), 4.87 (t, J = 1.7 Hz, 2H, Cp), 4.64 (d, J = 1.7 Hz, 2H, Cp), 4.28 (s,
7H, Cp and COCH2S); HRESIMS calcd for [M+H]+ C18H16FeN3O2S:
394.0313, found: 394.0303.
3-substituted-1H-1,2,4-triazole-5-thiol (4a–g)
As shown in Fig. 1, compound 4 was synthesized according to the
literature method [33,34]. 2-(Acetyl)hydrazinecarbothioamide or
2-(4-aroyl)hydrazinecarbothioamide (3) (10 mmol) and 5% sodium
hydroxide aqueous (40 mL) were added to a three-necked round-
bottomed flask. The mixture was refluxed for 2–3 h, and then it was
cooled to room temperature. The mixture was acidified with acetic
acid to about pH 5. After filtration, the solid was washed with cold
water and dried to afford 3-substituted-1H-1,2,4-triazole-5-thiol
(4) in 77–90% yield.
2.4.3. 1-Ferrocenyl-2-(3-phenyl-1H-1,2,4-triazol-5-ylthio)ethanone
(5c)
Orange solid, yield 57%; mp 156–159 ◦C; IR (KBr, cm−1): 3226,
1666; 1H NMR (CDCl3, 400 MHz), ı: 11.84 (s, 1H, NH triazole), 8.04
(s, 2H, Ar), 7.42 (s, 3H, Ar), 4.88 (s, 2H, Cp), 4.65 (s, 2H, Cp), 4.27
(s, 7H, Cp and COCH2S); HRESIMS calcd for [M+H]+ C20H18FeN3OS:
404.0520, found: 404.0513.
2.4.4. 1-Ferrocenyl-2-(3-p-tolyl-1H-1,2,4-triazol-5-ylthio)ethanone
(5d)
2.3. General procedure for the synthesis of
1-ferrocenyl-2-(3-substituted-1H-1,2,4-triazol-5-ylthio)ethanone
(5a–f)
Brown solid, yield 73%; mp 178–182 ◦C; IR (KBr, cm−1): 3163,
1656; 1H NMR (CDCl3, 400 MHz), ı: 11.99 (s, 1H, NH triazole), 7.91
(d, J = 7.8 Hz, 2H, Ar), 7.23 (d, J = 7.8 Hz, 2H, Ar), 4.87 (s, 2H, Cp),
4.62 (s, 2H, Cp), 4.30 (s, 2H, COCH2S), 4.26 (s, 5H, Cp), 2.38 (s, 3H,
CH3); HRESIMS calcd for [M+H]+ C21H20FeN3OS: 418.0677, found:
418.0643.
To a round-bottomed flask 3-substituted-1H-1,2,4-triazole-5-
thiol (4) (1.25 mmol), sodium hydride (60% dispersion in mineral
oil, 120 mg, 2.85 mmol), potassium iodide (190 mg, 1.14 mmol),
chloroacetyl ferrocene (300 mg, 1.14 mmol) and toluene (30 mL)
were added and the mixture was refluxed for 3–4 h. The reaction
mixture was cooled and poured into cold water (25 mL). The mix-
ture was extracted with ethyl acetate (3× 30 mL), and then the
combined extraction was dried over anhydrous magnesium sulfate.
After filtration, the solvent was removed under reduced pressure
in a rotary evaporator. The crude residue was purified by column
chromatography on silica gel to afford compound 5a–f in 57–87%
yield.
2.4.5. 1-Ferrocenyl-2-(3-(4-methoxyphenyl)-1H-1,2,4-triazol-5-
ylthio)ethanone (5e)
Red brown solid, yield 87%; mp 175–178 ◦C; IR (KBr, cm−1):
3184, 1653; 1H NMR(CDCl3, 400 MHz), 11.85 (s, 1H, NH triazole), ı:
7.95 (d, J = 6.0 Hz, 2H, Ar), 6.95 (d, J = 7.1 Hz, 2H, Ar), 4.87 (s, 2H, Cp),
4.63 (s, 2H, Cp), 4.29 (s, 2H, COCH2S), 4.26 (s, 5H, Cp), 3.84 (s, 3H,
CH3); HRESIMS calcd for [M+H]+ C21H20FeN3O2S: 434.0626, found:
434.0613.
2.4. Data of compounds 5
2.4.6. 1-Ferrocenyl-2-(3-(3-bromophenyl)-1H-1,2,4-triazol-5-
ylthio)ethanone (5f)
2.4.1. 1-Ferrocenyl-2-(3-methyl-1H-1,2,4-triazol-5-ylthio)ethanone
(5a)
Yellow solid, yield 80%; mp 154–156 ◦C; IR (KBr, cm−1): 3247,
1665; 1H NMR (CDCl3, 400 MHz), ı: 12.12 (s, 1H, NH triazole), 8.25
(s, 1H, Ar), 8.00 (d, J = 6.1 Hz, 1H, Ar), 7.52 (d, J = 7.4 Hz, 1H, Ar), 7.30
(t, J = 6.9 Hz, 1H, Ar), 4.88 (s, 2H, Cp), 4.68 (s, 2H, Cp), 4.27 (s, 5H, Cp),
4.22 (s, 2H, COCH2S); HRESIMS calcd for [M+H]+ C20H17BrFeN3OS:
481.9625, found: 481.9611.
Dark brown solid, yield 85%; mp 124–128 ◦C; IR (KBr, cm−1):
3228, 1664; 1H NMR (CDCl3, 400 MHz), ı: 11.22 (s, 1H, NH triazole),
4.85 (s, 2H, Cp), 4.60 (s, 2H, Cp), 4.26 (s, 7H, Cp and COCH2S), 2.45
(s, 3H, CH3); HRESIMS calcd for [M+H]+ C15H16FeN3OS: 342.0363,
found: 342.0355.