Tetrazoles 1, 3, 5 were prepared by methods [1, 2, 4].
Synthesis of Compounds 2 and 4 (General Method). K CO (5.44 mmol), Pd(OAc) (0.0092 mmol),
2
3
2
and the corresponding aryl halide (4.08 mmol) were added to a solution of the tetrazole 1 or 3 (2.72 mmol) in
DMF (4 ml). The reaction mixture was stirred at 120ºC, poured into water (25 ml), extracted with ethyl acetate
(
210 ml), and the combined extract was dried over anhydrous sodium sulfate. Solvent was evaporated and the
product was purified by column chromatography on SiO2.
E)-2-Methyl-5-styryltetrazole (2). Yield 80%; mp 87-88ºC. R 0.40 (hexane–ethyl acetate, 9:1).
(
f
1
H NMR spectrum, , ppm (J, Hz): 4.35 (3H, s, CH
3
); 7.14, 7.73 (1H, two d, J = 16.7, CH=CH); 7.38 (3H, m,
1
3
Ph); 7.56 (2H, d, Ph). C NMR spectrum, , ppm: 39.45 (CH ); 113.51 (CH=CH–Ph); 127.23, 128.93, 129.12;
1
3
+
35.80 (CH=CH–Ph); 136.40 (Ph); 164.48 (CN ). Mass spectrum, m/z: 187 [M+H] . Found, %: C 64.45;
4
H 5.30; N 30.25. C H N . Calculated, %: C 64.50; H 5.41; N 30.09.
1
0
10
4
(
E)-2-(2-Fluorostyryl)-5-phenyltetrazole (4). Yield 60%; mp 139-140ºC, R 0.30 (hexane–ethyl acetate,
f
1
9
:1). H NMR spectrum, , ppm (J, Hz): 7.17 (2H, m, Ar); 7.33 (1H, m, Ar); 7.50 (4H, m, Ar); 7.72, 8.14 (1H,
two d, J = 14.0, CH=CH); 8.21 (2H, d, Ar). C NMR spectrum, , ppm: 116.23, 116.52; 118.46 (CH=CH–Ph);
21.20, 124.75, 124.93, 127.00, 127.22, 129.08, 129.40, 130.72; 130.80 (CH=CH–Ph); 159.34, 162.28; 164.98
13
1
(
+
CN ). Mass spectrum, m/z: 287 [M+H] . Found, %: C 67.60; H 4.10; N 21.00. C H FN . Calculated, %:
4
1
5
1
1
4
C 67.66; H 4.16; N 21.04.
-((2-Fluorophenyl)ethynyl)-2-methyltetrazole (6). K CO (5.00 mmol), Pd(OAc) (0.008 mmol), and
5
2
3
2
the aryl halide (3.00 mmol) were added to a solution of the tetrazole (2.50 mmol) in DMF (4 ml). The reaction
mixture was stirred at 80ºC and then treated as in the method for the synthesis of tetrazoles 2, 4. Yield 84%; mp
1
1
10-111ºC. R 0.25 (hexane–dichloromethane, 7:3). H NMR spectrum, , ppm: 4.38 (3H, s, CH ); 7.20 (2H, m,
f
3
1
3
Ar); 7.39 (1H, s, Ar); 7.58 (1H, s, Ar). C NMR spectrum, , ppm: 39.93 (CH ); 81.84 (C≡C–Ar); 87.02 (C≡C–
Ar); 109.00, 116.6, 125.69, 133.38; 151.03 (CN ); 161.22, 166.23 (Ar). Mass spectrum, m/z: 203 [M+H] .
3
+
4
Found, %: C 59.70; H 3.30; N 27.60. C H FN . Calculated, %: C 59.40; H 3.49; N 27.71.
1
0
7
4
This work was carried out with the financial support of the RFFI (project 08-03-00247).
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1
2
.
.
V. N. Kizhnyaev and L. I. Vereshchagin, Usp. Khim., 72, 159 (2003).
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(
1980). [Chem. Heterocycl. Comp., 16, 658 (1980)].
3
.
.
E. Negishi (editor), Handbook of Organopalladium Chemistry for Organic Synthesis, John Wiley and
Sons, New York (2002), p. 3279
Yu. R. Pavlyukova, R. E. Trifonov, E. V. Yugai, P. A. Aleshunin, I. V. Tselinskii, and V. A. Ostrovskii,
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1
410