A. Khazaei et al. / Journal of Fluorine Chemistry 137 (2012) 123–125
125
Table 1 (Continued )
Entry
12
Alcohol
Time (min)
30
RSCN/RNCSa (%)
Yieldb,d (%)
70/30
90c
OH
13
14
60
10
92/8
81c
80c
OH
88/12
HO
O
O
15
16
24 h
24 h
Trace
NR
–
–
OH
OH
a
The ratio of RSCN/RNCS was determined by GC.
Isolated pure product.
b
c
A mixture of thiocyanate and isothiocyanate was obtained.
d
All the products are known compounds and were identified by comparison of their physical and spectral data with those of authentic samples.
References
between KSCN, NaSCN and NH4SCN as thiocyanating reagents,
NH4SCN appeared to give the best results. The products were
characterized by 1H NMR, IR, and by comparison with authentic
samples.
[1] R.G. Guy, in: S Patai (Ed.), The Chemistry of Cyanates and their Thio Derivatives,
John Wiley and Sons, New York, 1977.
[2] D. Landini, A. Maia, F. Montanari, F. Rolla, J. Org. Chem. 48 (1983) 3774–3777.
[3] A.R. Kiasat, M. Fallah-Mehrjardi, Bull. Korean Chem. Soc. 29 (2008) 2346–2348.
[4] A.S. Guram, Synlett (1993) 259–261.
3. Conclusion
[5] B. Mokhtari, A. Azhdari, R. Azadi, J. Sulfur Chem. 30 (2009) 585–589.
[6] N. Iranpoor, H. Firouzabadi, B. Akhlaghinia, R. Azadi, Synthesis (2004) 92–96.
[7] N. Iranpoor, H. Firouzabadi, R. Azadi, B. Akhlaghinia, J. Sulfur Chem. 26 (2005)
133–137.
[8] A. Kamal, G. Chouhan, Tetrahedron Lett. 46 (2005) 1489–1491.
[9] H. Lehmkuhl, F. Rabet, K. Hauchild, Synthesis (1977) 184–186.
[10] A.R. Kiasat, R. Badri, S. Sayyahi, Chin. Chem. Lett. 19 (2008) 1301–1304.
[11] S. Kondo, Y. Takeda, K. Tsuda, Synthesis (1988) 403–404.
[12] S. Kondo, Y. Takeda, K. Tsuda, Synthesis (1989) 862–864.
[13] B. Mokhtari, R. Azadi, S. Rahmani-Nezhad, Tetrahedron Lett. 50 (2009) 6588–6589.
[14] N. Iranpoor, H. Firouzabadi, R. Azadi, Tetrahedron Lett. 47 (2006) 5531–5534.
[15] Y. Tamura, T. Kawasaki, M. Adachi, M. Tanio, Y. Kita, Tetrahedron Lett. (1977)
4417–4420.
In conclusion, SelectfluorTM has proved to be an effective
reagent for the electrophilic thiocyanates or isothiocyanates of
alcohols under heterogeneous and neutral conditions.
This present method is featured with relatively mild reaction
conditions, simple operation, broad substrate scope, excellent
selectivity and also avoids tedious purifications and the use of toxic
reagents. This method provides the direct access to a wide range of
potentially valuable biologically well-defined thiocyanates.
[16] F. Mohanazadeh, M. Aghvami, Tetrahedron Lett. 48 (2007) 7240–7242.
[17] N. Iranpoor, H. Firouzabadi, N. Nowrouzi, Tetrahedron 62 (2006) 5498–5501.
[18] R.G. Syvret, K.M. Butt, T.P. Nguyen, V.L. Bulleck, R.D. Rieth, J. Org. Chem. 67 (2002)
4487–4493.
[19] B. Mokhtari, R. Azadi, E. Mardani, Tetrahedron Lett. 53 (2012) 491–493.
[20] R. Azadi, B. Mokhtari, M.A. Makaremi, Chin. Chem. Lett. 23 (2012) 77–80.
[21] N. Iranpoor, H. Firouzabadi, H.R. Shaterian, J. Chem. Res. (1999) 676–677.
[22] N. Iranpoor, H. Firouzabadi, H.R. Shaterian, Synlett (2000) 65–66.
[23] N. Iranpoor, H. Firouzabadi, H.R. Shaterian, Tetrahedron Lett. 43 (2002) 3439–3441.
[24] P.T. Nyffeler, S.G. Duron, M.D. Burkart, S.P. Vincent, C.H. Wong, Angew. Chem. Int.
Ed. 44 (2005) 192–212.
[25] Y. Takeuchi, T. Tarui, N. Shibata, Org. Lett. 2 (2000) 639–642.
[26] N. Shibata, T. Tarui, Y. Doi, K.L. Kirk, Angew. Chem. Int. Ed. 40 (2001) 4461–4463.
[27] A.G. Gilicinski, G.P. Pez, R.G. Syvret, G.S. Lal, J. Fluorine Chem. 59 (1992) 157–162.
[28] M. Kirihara, S. Naito, Y. Ishizuka, H. Hanai, T. Noguchi, Tetrahedron Lett. 52 (2011)
3086–3089.
[29] Z. Jin, B. Xu, G.B. Hammond, Tetrahedron Lett. 52 (2011) 1956–1959.
[30] M.H. Daniels, J. Hubbs, Tetrahedron Lett. 52 (2011) 3543–3546.
[31] S. Stavber, M. Jereb, M. Zupan, Chem. Commun. (2002) 488–489.
[32] J.S. Yadav, B.V. Subba Reddy, Y. Jayasudhan Reddy, Chem. Lett. 37 (2008) 652–653.
[33] A. Khazaei, A. Rostami, Z. Tanbakouchian, Z. Zinati, J. Braz. Chem. Soc. 17 (2006)
206–208.
4. Experimental
4.1. General procedure for thiocyanation or isothiocyanation of
alcohols by in situ generation of [+SCN]
The SelectfluorTM (1.5 mmol) and ammonium thiocyanate
(3 mmol) were dissolved in acetonitrile (7 mL) at room tempera-
ture. The reaction mixture was stirred for 20 min to form a yellow
solid. Next, alcohol (1 mmol) was added to the reaction mixture.
After completion of the reaction (TLC), mixture was filtered and
then diluted with water (10 mL) and then extracted with diethyl
ether (3Â 10 mL), the combined organic layer was dried over
anhydrous Na2SO4. The solvent was removed under reduced
pressure and reaction mixture was passed through a short column
of silica gel using n-hexane/ethyl acetate (8/2) as eluent. Then
solvent was evaporated to dryness to afford the pure product.
[34] A.Khazaei,A.Rostami,Z.Tanbakouchian,Z.Zinati,Catal.Commun.7(2006) 214–217.
[35] A. Khazaei, A. Rostami, S. Rahmati, M. Mahboubifar, Phosphorus Sulfur Silicon
Relat. Elem. 182 (2007) 537–544.
Acknowledgments
[36] A. Khazaei, A. Rostami, M. Mahboubifar, Catal. Commun. 8 (2007) 383–388.
[37] A. Khazaei, M.A. Zolfigol, A. Rostami, A. Ghorbani-Choghamarani, Catal. Commun.
8 (2007) 543–547.
[38] A. Khazaei, A.A. Manesh, A. Rostami, J. Chem. Res. (2005) 391–393.
[39] A. Khazaei, A. Alizadeh, R. Ghorbani Vaghei, Molecules 6 (2001) 253–257.
The authors acknowledge to Bu-Ali Sina University Research
Councils, Center of Excellence in Development of Chemistry
Methods (CEDCM) and National Foundation of Elites (BMN) for
support of this work.