2
26
B. Kaboudin, D. Elhamifar
SHORT PAPER
1
S
H NMR (CDCl , 250 MHz): d = 3.80 (3 H, s), 4.05 (2 H, s), 6.72
3
(
1 H, br, NH ), 6.89 (2 H, d, J = 8.25 Hz), 7.17 (2 H, d, J = 8.25 Hz),
BrH2C
(EtO)2P SCH2
2
S
C
7.76 (1 H, br, NH2).
EtOH
h, reflux
CN
+
P4S10
NH2
13
C NMR (CDCl , 62.9 MHz): d = 159.3, 130.6, 130.5, 126.9,
3
3
1
14.7, 55.3, 51.6.
3
: 50%
3
-Methoxyphenylthioacetamide (2k)
Scheme 2
White crystals; mp 107–113 °C (n-hexane–CH Cl ).
2
2
1
H NMR (CDCl , 250 MHz): d = 3.80 (3 H, s), 4.08 (2 H, s), 6.72–
3
make this method an attractive and a useful addition to 6.92 (4 H, m), 7.15–7.35 (1 H, m), 7.81 (1 H, br, NH ).
2
1
3
current methodologies.
C NMR (CDCl , 62.9 MHz): d = 207.1, 181.7, 160.2, 136.2,
3
1
30.4, 121.6, 115.0, 113.5, 55.3, 52.1.
All starting materials were commercial available and were distilled
or recrystallized before use. Mps were obtained on a Buchi 510 and
are uncorrected. IR spectra were determined using a FT-IR Bruker-
Vector 22. NMR spectra were taken with a 250 MHz Bruker
4
-(O,O-Diethyldithiophosphorylmethyl)phenylthioacetamide
(
3)
Colorless oil.
1
1
H NMR (CDCl , 250 MHz): d = 1.23 (3 H, t, J = 7.0 Hz), 3.84–4.20
Avance instrument with TMS as the internal reference for H and
3
1
3
31
(6 H, m), 7.31 (1 H, t, J = 7.5 Hz), 7.40–7.58 (2 H, m), 7.71 (1 H, d,
C and H PO for P NMR. Silica gel column chromatography was
3
4
J = 7.5 Hz), 7.85 (1 H, s), 8.13 (1 H, br, NH2).
carried out with Silica gel 100 (Merck No. 10184). Merck Silica gel
0 F254 and plates No. 5744 were used for preparative TLC.
6
31
P NMR (CDCl , 101.2 MHz): d = 93.00.
3
1
3
C NMR (CDCl , 62.9 MHz): d = 207.1, 181.7, 137.8, 137.7,
3
Conversion of Nitriles to Thioamides; General Procedure
A solution of P4S10 (10 mmol) in EtOH (5 mL) was stirred for 1 h.
Nitrile (5 mmol) was added and the resulting solution was heated to
1
32.4, 128.8, 127.7, 126.1, 64.2 (d, J = 6.3 Hz), 37.2 (d, J = 3.8
PC
PC
Hz), 15.8 (d, JPC = 8.2 Hz).
reflux for 2–6.5 h. The mixture was then washed with CHCl (200
3
mL), the organic phase was dried over CaCl , and concentrated in
vacuo. Chromatography (EtOAc–n-hexane, 40:60) of the residue
2
Acknowledgment
gave the pure thioamides in 47–95% yield.
The Institute for Advanced Studies in Basic Sciences (IASBS) is
thanked for supporting this work.
4
-Bromothiobenzamide (2b)
White crystals; mp 138–142 °C (n-hexane–CH Cl ).
2
2
References
1
H NMR (CDCl , 250 MHz): d = 7.18 (1 H, br, NH ), 7.54 (2 H, d,
3
2
J = 6.7 Hz), 7.74 (2 H, d, J = 6.78 Hz), 7.74 (1 H, br, NH2).
1
(1) (a) Oare, D. A.; Sanner, M. A.; Heathcock, C. H. J. Org.
Chem. 1990, 55, 132. (b) Heathcock, C. H.; Davidson, S. K.;
Mills, S. G.; Sanner, M. A. J. Org. Chem. 1992, 57, 2531.
3
C NMR (CDCl , 62.9 MHz): d = 201.2, 181.8, 138.0, 131.7,
3
1
28.4, 126.9.
(
c) Magnus, P.; Mendoza, J. S.; Stamford, A.; Ladlow, M.;
Willis, P. J. Am. Chem. Soc. 1992, 114, 10232. (d) Kim, G.;
Chu-Moyer, M. Y.; Danishefsky, S. J.; Schulte, G. K. J. Am.
Chem. Soc. 1993, 115, 30. (e) Takahata, H.; Banba, Y.;
Mozumi, M.; Yamazaki, T. Heterocycles 1986, 24, 947.
3
-Chlorothiobenzamide (2e)
White crystals; mp 112–114 °C (n-hexane–CH Cl ).
2
2
1
H NMR (CDCl , 250 MHz): d = 7.22 (1 H, br, NH ) 7.35 (1 H, t,
3
2
J = 7.75 Hz), 7.48 (1 H, ddd, J = 7.75, 1.75, 1.0 Hz), 7.63 (1 H, br,
(
f) Takahata, H.; Yamazaki, T. Heterocycles 1988, 27,
1953. (g) Hurd, R. N.; Delmater, G. T. Chem. Rev. 1961, 61,
5.
NH ), 7.72 (1 H, ddd, J = 7.75, 1.75, 1.0 Hz), 7.86 (1 H, t, J = 1.75
Hz).
2
4
1
3
C NMR (CDCl , 62.9 MHz): d = 201.1, 181.7, 140.8, 134.6,
(2) (a) Kindler, K. Justus Liebigs Ann. Chem. 1923, 431, 187.
(b) Zbruyev, O. I.; Stiasni, N.; Kapper, C. O. J. Comb. Chem.
3
1
31.8, 129.7, 127.2, 124.8.
2003, 5, 145.
2
,4-Dichlorothiobenzamide (2f)
(3) Wang, C.-H.; Hwang, F.-Y.; Horng, J.-M.; Chen, C.-T.
White crystals; mp 85–90 °C (n-hexane–CH Cl ).
Heterocycles 1979, 12, 1191.
4) Albert, A. Ber. Dtsch. Chem. Ges. 1915, 48, 470.
5) Taylor, E. C.; Zoltewicz, J. A. J. Am. Chem. Soc. 1960, 82,
2
2
(
(
1
H NMR (CDCl , 250 MHz): d = 7.22 (1 H, br, NH ) 7.28 (1 H, dd,
3
2
J = 8.5, 2 Hz), 7.40 (1 H, d, J = 2.0 Hz), 7.65 (1 H, d, J = 8.5 Hz),
.08 (1 H, br, NH2).
2656.
8
(6) Liboska, R.; Zyka, D.; Bobek, M. Synthesis 2002, 1649.
1
3
C NMR (CDCl , 62.9 MHz): d = 200.1, 181.7, 138.7, 136.4,
3
(7) (a) Benner, S. A. Tetrahedron Lett. 1981, 22, 1851.
1
31.6, 129.8, 129.0, 127.4.
(
b) Benner, S. A. Tetrahedron Lett. 1981, 22, 1855.
(
8) Shiao, M. J.; Lai, L. L.; Ku, W. S.; Lin, P. Y.; Hwu, J. R. J.
Org. Chem. 1993, 58, 4772.
4
-Chlorophenylthioacetamide (2i)
White crystals; mp 97–102 °C (n-hexane–CH Cl ).
2
2
(9) Brillon, D. Synth. Commun. 1992, 22, 1397.
(10) Bagley, M. C.; Chapaneri, K.; Glover, C.; Merritt, E. A.
Synlett 2004, 2615.
1
H NMR (CDCl , 250 MHz): d = 4.48 (2 H, s), 6.72 (1 H, br, NH )
3
2
7
.22 (2 H, d, J = 8.0 Hz), 7.35 (1 H, d, J = 8.0 Hz), 7.84 (1 H, br,
(
11) Encyclopedia of Reagents for Organic Synthesis, Vol. 6;
NH2).
Paquette, L. A., Ed.; J. Wiley & Sons: New York, 1995,
1
3
C NMR (CDCl , 62.9 MHz): d = 206.8, 181.7, 133.9, 133.5,
3
4138.
1
30.7, 129.4, 51.2.
(
(
12) Kaboudin, B.; Norouzi, H. Synthesis 2004, 2035.
13) Gilbert, E. E.; Rumanowski, E. J.; Newallis, P. E. J. Chem.
Eng. Data 1968, 13, 130.
4
-Methoxyphenylthioacetamide (2j)
White crystals; mp 129–132 °C (n-hexane–CH Cl ).
2
2
Synthesis 2006, No. 2, 224–226 © Thieme Stuttgart · New York