Transition-Metal-Free, Chemoselective Aerobic Oxidations of Sulfides and Alcohols with Potassium Nitrate and Pyridinium Tribromide or Bromine

Abstract

An efficient oxidation of sulfides with air catalyzed by the combination of potassium nitrate with pyridinium tribromide under transition-metal-free conditions was reported. By replacing pyridinium tribromide with bromine, the reaction system was also useful in the oxidation of alcohols. All reactions afforded the corresponding products in good to excellent yields with high chemoselectivities.

Key words

aerobic oxidation - sulfide - alcohol - chemoselectivity - transition-metal-free

References and Notes

• 1a Drabowicz J. Kielbasinski P. Mikolajczyk M. In The Chemistry of Sulfones and Sulfoxides   Patai S. Rappoport Z. Stirling C. Wiley; Chichester: 1988.  p.233-278  
• 1b Sulfur Reagents in Organic Synthesis   Metzner P. Thuillier A. Academic Press; London: 1994. 
• 1c Hudlicky M. Oxidations in Organic Chemistry   American Chemical Society; Washington DC: 1990. 
• 1d Fernandez M. Tojo G. In Oxidation of Alcohols to Aldehydes and Ketones: A Guide to Current Common Practice   Tojo G. Springer; New York: 2006. 
• 2a Shi Z.-Z. Zhang C. Li S. Pan D.-L. Ding S.-T. Cui Y.-X. Jiao N. Angew. Chem. Int. Ed.  2009,  48:  4572 
• 2b Zhang C. Jiao N. J. Am. Chem. Soc.  2010,  132:  28 
• 2c He X.-J. Shen Z.-L. Mo W.-M. Sun N. Hu B.-X. Hu X.-Q. Adv. Synth. Catal.  2009,  351:  89 
• 2d Miao C.-X. He L.-N. Wang J.-L. Wu F. J. Org. Chem.  2010,  75:  257 
• 3a Legros J. Bolm C. Angew. Chem. Int. Ed.  2003,  42:  5487 
• 3b Hosseinpoor F. Golchoubian H. Tetrahedron Lett.  2006,  47:  5195 
• 3c Liu R. Wu L.-Z. Feng X.-M. Zhang Z. Li Y.-Z. Wang Z.-L. Inorg. Chim. Acta  2007,  360:  656 
• 3d Rosa MD. Lamberti M. Pellecchia C. Scettri A. Villano R. Soriente A. Tetrahedron Lett.  2006,  47:  7233 
• 3e Bolm C. Bienewald F. Angew. Chem., Int. Ed. Engl.  1995,  34:  2883 
• 3f Karimi B. Nezhad MG. Clark JH. Org. Lett.  2005,  7:  625 
• 3g Scarso A. Strukul G. Adv. Synth. Catal.  2005,  347:  1227 
• 3h Yuan Y. Bian Y.-B. Tetrahedron Lett.  2007,  48:  8518 
• 3i Shi F. Tse MK. Kaiserand HM. Beller M. Adv. Synth. Catal.  2007,  349:  2425 
• 3j Wang X.-S. Wang X.-W. Guo H.-C. Wang Z. Ding K.-L. Chem. Eur. J.  2005,  11:  4078 
• 4a Martin SE. Garrone A. Tetrahedron Lett.  2003,  44:  549 
• 4b Shulpin GB. Suss-Fink G. Shulpina LS.
  J. Mol. Catal. A: Chem.  2001,  170:  17 
• 4c Liu J.-H. Wang F. Sun K.-P. Xu X.-L. Adv. Synth. Catal.  2007,  349:  2439 
• 4d Kantam ML. Yadav J. Laha S. Sreedhar B. Bhargava S. Adv. Synth. Catal.  2008,  350:  2575 
• 4e Roy MN. Poupon JC. Charette AB. J. Org. Chem.  2009,  74:  8510 
• 5a Martin SE. Rossi LI. Tetrahedron Lett.  2001,  42:  7147 
• 5b Boring E. Geletii YV. Hill CL. J. Am. Chem. Soc.  2001,  123:  1625 
• 5c Komatsu N. Uda M. Suzuki H. Chem. Lett.  1997,  1229 
• 5d Riley DP. Shumate RE.
  J. Am. Chem. Soc.  1984,  106:  3179 
• 5e Iwahama T. Sakaguchi S. Ishii Y. Tetrahedron Lett.  1998,  39:  9059 
• 5f Semmelhack MF. Schmid CR. Cortés DA. Chou CS. J. Am. Chem. Soc.  1984,  106:  3374 
• 5g Kaneda K. Fujie Y. Ebitani K. Tetrahedron Lett.  1997,  38:  9023 
• 5h Iwahama T. Yosino Y. Keitoku T. Sakaguchi S. Ishii Y. J. Org. Chem.  2000,  65:  6502 
• 5i Jia C.-G. Jing F.-Y. Hu W.-D. Huang M.-Y. Jiang Y.-Y. J. Mol. Catal.  1994,  91:  139 
• 5j Chan W.-L. Sung H.-J. Koo S.-Y. Han M.-J. Chi K.-W. Tetrahedron Lett.  2009,  50:  559 
• 5k Minisci F. Punta C. Recupero F. Fontana F. Pedulli GF. Chem. Commun.  2002,  688 
• 5l Martin SE. Suarez DF. Tetrahedron Lett.  2002,  43:  4475 
• 5m Kinen CO. Rossi LI. de Rossi RH. J. Org. Chem.  2009,  74:  7132 
• 6a Zhang H. Chen C.-Y. Liu R.-H. Xu Q. Zhao W.-Q. Molecules  2010,  15:  83 
• 6b Zhang H. Chen C.-Y. Liu R.-H. Xu Q. Liu J.-H. Synth. Commun.   2008,  38:  4445 
• 6c Xie Y. Mo W.-M. Xu D. Shen Z.-L. Sun N. Hu B.-X. Hu X.-Q. J. Org. Chem.  2007,  72:  4288 
• 6d Liu R.-H. Dong C.-Y. Liang X.-M. Wang X.-J. Hu X.-Q. J. Org. Chem.  2005,  70:  729 
• 6e Liu R.-H. Liang X.-M. Dong C.-Y. Hu X.-Q. J. Am. Chem. Soc.  2004,  126:  4112 
• 6f Yang G.-Y. Wang W. Zhu W.-M. An C.-B. Gao X.-Q. Song M.-P. Synlett  2010,  437 
• 7 Djerassi C. Scholz CR. J. Am. Chem. Soc.  1948,  70:  417 
• 8 Doxsee KM. Hutchison JE. In Green Organic Chemistry   Thompson Brooks/Cole; Pacific Grove CA: 2004.  p.120-124  
• 9 Suarez AR. Baruzzi AM. Rossi LI. J. Org. Chem.  1998,  63:  5689 
• 10a Bosch E. Kochi JK. J. Org. Chem.  1996,  60:  3172 
• 10b Roy S. Baiker A. Chem. Rev.  2009,  109:  4054 
• 11 Silverstein RM. Webster FX. Kiemle DJ. In Spectrometric Identification of Organic Compounds   John Wiley and Sons, Inc.; New York: 2005. 
• 12 Thiemann M. Scheibler E. Wiegand KW. Nitric Acid, Nitrous Acid, and Nitrogen Oxides, In Ullmann’s Encyclopedia of Industrial Chemistry   Wiley-VCH; Weinheim: 2005. 

13

General Methods
^¹H NMR and ^¹³C NMR spectra were obtained with a Bruker AVANCE 600 spectrometer in CDCl₃ with TMS as an internal standard. Infrared spectra were recorded with a Bruker Tensor 27 FT-IR spectrometer using KBr pellets. GC-MS was performed on a FINNIGAN Trace DSQ chromatograph.
Procedure for Oxidation of Sulfide Using KNO ₃ -PyHBr ₃ /Br ₂ as Catalyst A typical experiment was carried out in an open reaction tube. Sulfide (1 mmol) was added to the mixture of KNO₃ (0.1 mmol) and PyHBr₃ (or bromine; 0.15 mmol) in MeCN (2 mL). The reaction mixture was stirred under aerial conditions at r.t. The reaction progress was detected by
GC and TLC. After the starting material had disappeared, Na₂S₂O₃ aq solution was used to quench the reaction. CH₂Cl₂ was added to the reaction mixture, and the two phases were separated. The aqueous layer was extracted with CH₂Cl₂. The combined organic layers were washed with H₂O and dried over MgSO₄. The solvent was removed under vacuum, and the residue was purified by chromatography. Representative Spectral Data of Sulfoxide - Methyl Phenyl Sulfoxide IR (KBr): ν_max = 3265, 1477, 1038, 749, 692 cm^-¹. ^¹H NMR (600 MHz, CDCl₃): δ = 2.73 (s, 3 H), 7.48-7.54 (m, 3 H), 7.64-7.65 (d, 2 H, J = 7.44 Hz). ^¹³C NMR (150 MHz, CDCl₃): δ = 44.13, 123.6, 129.5, 131.2, 145.7. MS (EI, 70 eV): m/z (%) = 140 [M⁺].^³h Procedure for Oxidation of Benzaldehydes and Acetophenones Using KNO ₃ -Br ₂ /PyHBr ₃ as Catalyst A typical experiment was carried out in an open reaction tube. Benzaldehyde or acetophenone (1 mmol) was added to the mixture of KNO₃ (0.2 mmol) and bromine (0.3 mmol) in MeCN (2 mL). The reaction mixture was stirred under aerial conditions at 50 ˚C. The reaction progress was detected by GC and TLC. After the starting material had disappeared, Na₂S₂O₃ aq solution was used to quench the reaction. CH₂Cl₂ was added to the reaction mixture, and the two phases were separated. The aqueous layer was extracted with CH₂Cl₂. The combined organic layers were washed with H₂O and dried over MgSO₄. The solvent was removed under vacuum, and the residue was purified by chromatography.
Representative Spectral Data of Aldehyde - Benzaldehyde
IR (KBr): ν_max = 3064, 2819, 1701, 1311, 1203, 746 cm^-¹. ^¹H NMR (600 MHz, CDCl₃): δ = 7.51-7.54 (t, 2 H, J = 7.54 Hz), 7.61-7.64 (t, 1 H, J = 7.43 Hz), 7.87-7.88 (d, 2 H, J = 7.69 Hz), 10.00 (s, 1 H). ^¹³C NMR (150 MHz, CDCl₃): δ = 129.0, 129.7, 134.4, 136.4, 192.4. MS (EI, 70 eV): m/z (%) = 106 [M⁺].^²c