Recent Progress in the Metal-Free or Nonnoble-Metal-Catalyzed Oxidation of Alkynes by Using Pyridine N-Oxides as External Oxidants

Abstract

Catalytic oxidation of alkynes by using pyridine N-oxides as external oxidants has proven to be a powerful tool in organic synthesis, allowing the assembly of functionalized carbocycles and heterocycles in a remarkably efficient manner. Recent progress in this area is reviewed with emphasis on metal-free or nonnoble-metal-catalyzed oxidative cyclizations.

Key words

green chemistry - heterocycles - alkynes - oxidation - catalysis

• References

• 1a Ye L, Cui L, Zhang G, Zhang L. J. Am. Chem. Soc. 2010; 132: 3258
• 1b Ye L, He W, Zhang L. J. Am. Chem. Soc. 2010; 132: 8550

For reviews on intramolecular oxidations of alkynes, see:
• 2a Xiao J, Li X. Angew. Chem. Int. Ed. 2011; 50: 7226
• 2b Yeom H.-S, Shin S. Acc. Chem. Res. 2014; 47: 966

For a review on intermolecular oxidation of alkynes, see:
• 2c Zhang L. Acc. Chem. Res. 2014; 47: 877

For recent selected examples, see:
• 3a Chen H, Zhang L. Angew. Chem. Int. Ed. 2015; 54: 11775
• 3b Wang Y, Zheng Z, Zhang L. J. Am. Chem. Soc. 2015; 137: 5316
• 3c Rassadin VA, Boyarskiy VP, Kukushkin VYu. Org. Lett. 2015; 17: 3502
• 3d Ji K, Liu X, Du B, Yang F, Gao J. Chem. Commun. 2015; 51: 10318
• 3e Schulz J, Jašíková L, Škríba A, Roithová J. J. Am. Chem. Soc. 2014; 136: 11513
• 3f Wang T, Shi S, Hansmann MM, Rettenmeier E, Rudolph M, Hashmi AS. K. Angew. Chem. Int. Ed. 2014; 53: 3715
• 3g Wang T, Shi S, Rudolph M, Hashmi AS. K. Adv. Synth. Catal. 2014; 356: 2337
• 3h Shu C, Li L, Xiao X.-Y, Yu Y.-F, Ping Y.-F, Zhou J.-M, Ye L.-W. Chem. Commun. 2014; 50: 8689
• 3i Shu C, Li L, Yu Y.-F, Jiang S, Ye L.-W. Chem. Commun. 2014; 50: 2522
• 3j Dos Santos M, Davies PW. Chem. Commun. 2014; 50: 6001
• 3k Li J, Ji K, Zheng R, Nelson J, Zhang L. Chem. Commun. 2014; 50: 4130
• 3l Wu G, Zheng R, Nelson J, Zhang L. Adv. Synth. Catal. 2014; 356: 1229
• 3m Talbot EP. A, Richardson M, McKenna JM, Toste FD. Adv. Synth. Catal. 2014; 356: 687

For selected reviews on gold carbene chemistry, see:
• 4a Dorel R, Echavarren AM. Chem. Rev. 2015; 115: 9028
• 4b Qian D, Zhang J. Chem. Soc. Rev. 2015; 44: 677
• 4c Wang Y, Muratore ME, Echavarren AM. Chem. Eur. J. 2015; 21: 7332
• 4d Davies PW, Garzón M. Asian J. Org. Chem. 2015; 4: 694
• 4e Fensterbank L, Malacria M. Acc. Chem. Res. 2014; 47: 953
• 4f Obradors C, Echavarren AM. Acc. Chem. Res. 2014; 47: 902
• 4g Hashmi AS. K. Acc. Chem. Res. 2014; 47: 864
• 4h Hashmi AS. K. Angew. Chem. Int. Ed. 2010; 49: 5232

For relevant Rh-catalyzed intermolecular oxidations of alkynes, see:
• 5a Zhang X, Qi Z, Li X. Angew. Chem. Int. Ed. 2014; 53: 10794
• 5b Liu R, Winston-McPherson GN, Yang Z.-Y, Zhou X, Song W, Guzei IA, Xu X, Tang W. J. Am. Chem. Soc. 2013; 135: 8201

For a relevant Pd-catalyzed intermolecular oxidation of alkynes, see:
• 5c Sawama Y, Takubo M, Mori S, Monguchi Y, Sajiki H. Eur. J. Org. Chem. 2011; 3361

For Cu(I)-catalyzed oxidative cyclizations of alkynyl oxiranes and oxetanes by an allenyloxypyridinium intermediate pathway, see:
• 5d Gronnier C, Kramer S, Odabachian Y, Gagosz F. J. Am. Chem. Soc. 2012; 134: 828
• 6 Chen D.-F, Han Z.-Y, He Y.-P, Yu J, Gong L.-Z. Angew. Chem. Int. Ed. 2012; 51: 12307
• 7 Graf K, Rühl CL, Rudolph M, Rominger F, Hashmi AS. K. Angew. Chem. Int. Ed. 2013; 52: 12727
• 8 Li L, Zhou B, Wang Y.-H, Shu C, Pan Y.-F, Lu X, Ye L.-W. Angew. Chem. Int. Ed. 2015; 54: 8245
• 9a Karad SN, Liu R.-S. Angew. Chem. Int. Ed. 2014; 53: 5444
• 9b Wang K.-B, Ran R.-Q, Xiu S.-D, Li C.-Y. Org. Lett. 2013; 15: 2374
• 9c Yang L.-Q, Wang K.-B, Li C.-Y. Eur. J. Org. Chem. 2013; 2775
• 9d Dateer RB, Pati K, Liu R.-S. Chem. Commun. 2012; 48: 7200
• 9e Mukherjee A, Dateer RB, Chaudhuri R, Bhunia S, Karad SN, Liu R.-S. J. Am. Chem. Soc. 2011; 133: 15372
• 9f Vasu D, Hung H.-H, Bhunia S, Gawade SA, Das A, Liu R.-S. Angew. Chem. Int. Ed. 2011; 50: 6911
• 9g Li C.-W, Pati K, Lin G.-Y, Sohel SM. A, Hung H.-H, Liu R.-S. Angew. Chem. Int. Ed. 2010; 49: 9891

For our recent study on the gold-catalyzed tandem reactions based on ynamides, see:
• 10a Shu C, Wang Y.-H, Zhou B, Li X.-L, Ping Y.-F, Lu X, Ye L.-W. J. Am. Chem. Soc. 2015; 137: 9567
• 10b Zhou A.-H, He Q, Shu C, Yu Y.-F, Liu S, Zhao T, Zhang W, Lu X, Ye L.-W. Chem. Sci. 2015; 6: 1265
• 10c Xiao X.-Y, Zhou A.-H, Shu C, Pan F, Li T, Ye L.-W. Chem. Asian J. 2015; 10: 1854
• 10d Shen C.-H, Pan Y, Yu Y.-F, Wang Z.-S, He W, Li T, Ye L.-W. J. Organomet. Chem. 2015; 795: 63
• 10e Li L, Zhou B, Ye L.-W. Youji Huaxue 2015; 35: 655
• 10f Li L, Shu C, Zhou B, Yu Y.-F, Xiao X.-Y, Ye L.-W. Chem. Sci. 2014; 5: 4057
• 10g Pan F, Liu S, Shu C, Lin R.-K, Yu Y.-F, Zhou J.-M, Ye L.-W. Chem. Commun. 2014; 50: 10726
• 10h Shen C.-H, Li L, Zhang W, Liu S, Shu C, Xie Y.-E, Yu Y.-F, Ye L.-W. J. Org. Chem. 2014; 79: 9313

For relevant examples of gold-catalyzed alkyne oxidation that do not proceed via gold carbene intermediates, see:
• 11a Qian D, Hu H, Liu F, Tang B, Ye W, Wang Y, Zhang J. Angew. Chem. Int. Ed. 2014; 53: 13751
• 11b Chen M, Chen Y, Sun N, Zhao J, Liu Y, Li Y. Angew. Chem. Int. Ed. 2015; 54: 1200