FeBr₃-Catalyzed Tandem Reaction of N-Propargylamides with Disulfides or Diselenides for the Synthesis of Oxazole Derivatives

Abstract

A methodology of FeBr₃-catalyzed tandem reaction of N-propargylamides with disulfides or diselenides for the formation of oxazole derivatives has been developed. The strategy includes several steps in one pot. Series of N-propargylamides and disulfides were suitable as substrates in this transformation for synthesizing the corresponding oxazole derivatives in moderate to good yields.

Key words

FeBr₃ - tandem - N-propargylamides - disulfides - oxazole

• References

• 1 Alonso F, Beletskaya IP, Yus M. Chem. Rev. 2004; 104: 3079
• 2a Lindquist N, Fenical W. J. Am. Chem. Soc. 1991; 113: 2303
• 2b Garfunkle J, Ezzili C, Rayl TJ, Hochstatter DG, Hwang I, Boger DL. J. Med. Chem. 2008; 51: 4392
• 3a Zheng M, Huang L, Huang H, Li X, Wu W, Jiang H. Org. Lett. 2014; 16: 5906
• 3b Yu J, Yang H, Fu H. Adv. Synth. Catal. 2014; 356: 3669
• 3c Yu X, Xin X, Wan B, Li X. J. Org. Chem. 2013; 78: 4895
• 3d Hu Y, Yi R, Wang C, Xin X, Wu F, Wan B. J. Org. Chem. 2014; 79: 3052
• 3e Bartoli G, Cimarelli C, Cipolletti R, Diomedi S, Giovannini R, Mari M, Marsili L, Marcantoni E. Eur. J. Org. Chem. 2012; 630
• 3f Kreisberg JD, Magnus P, Shinde S. Tetrahedron Lett. 2002; 43: 7393
• 4a Weyrauch JP, Hashmi AS. K, Schuster A, Hengst T, Schetter S, Littmann A, Rudolph M, Hamzic M, Visus J, Rominger F, Frey W, Bats JW. Chem. Eur. J. 2010; 16: 956
• 4b Hashmi AS. K, Weyrauch JP, Frey W, Bats JW. Org. Lett. 2004; 6: 4391
• 4c Egorova OA, Seo H, Kim Y, Moon D, Rhee YM, Ahn KH. Angew. Chem. Int. Ed. 2011; 50: 11446
• 5a Arcadi A, Cacchi S, Cascia L, Fabrizi G, Marinelli F. Org. Lett. 2001; 3: 2501
• 5b Beccalli EM, Borsini E, Broggini G, Palmisano G, Sottocornola S. J. Org. Chem. 2008; 73: 4746
• 5c Merkul E, Müller TJ. J. Chem. Commun. 2006; 4817
• 6 Kreisberg JD, Magnus P, Shinde S. Tetrahedron Lett. 2002; 43: 7393
• 7a Senadi GC, Hu W.-P, Hsiao JS, Vandavasi JK, Chen C.-Y, Wang J.-J. Org. Lett. 2012; 14: 4478
• 7b Malosh CF, Ready JM. J. Am. Chem. Soc. 2004; 126: 10240
• 7c Patil NT, Singh V. Chem. Commun. 2011; 47: 11116
• 8a Meng X, Kim S. Org. Biomol. Chem. 2011; 9: 4429
• 8b Onizawa Y, Kusama H, Iwasawa N. J. Am. Chem. Soc. 2008; 130: 802
• 8c Kusama H, Yamabe H, Onizawa Y, Hoshino T, Iwasawa N. Angew. Chem. Int. Ed. 2005; 44: 468
• 9 Milton MD, Inada Y, Nishibayashi Y, Uemura S. Chem. Commun. 2004; 2712
• 10a Bolm C, Legros J, Le Paih J, Zani L. Chem. Rev. 2008; 37: 1108
• 10b Bolm C, Legros J, Le Paih J, Zani L. Chem. Rev. 2004; 104: 2617
• 11a Du HA, Tang RY, Deng CL, Liu Y, Li JH, Zhang XG. Adv. Synth. Catal. 2011; 353: 2739
• 11b Correa A, Carril M, Bolm C. Angew. Chem. Int. Ed. 2008; 47: 2880
• 11c Correa A, Elmore S, Bolm C. Chem. Eur. J. 2008; 14: 3527
• 12 Typical Procedure Under air atmosphere, a reaction tube was charged with N-(prop-2-yn-1-yl)benzamide (1a, 0.2 mmol), diphenyldisulfane (2a, 0.4 mmol), FeBr₃ (10 mol%), I₂ (0.8 mmol), and MeCN (2 mL). The vessel was sealed and heated at 100 °C (oil bath temperature) for 12 h and then cooled to room temperature. The reaction mixture was washed with sat. Na₂S₂O₃ (2 × 15 mL) and then brine (1 × 15 mL). After the aqueous layer was extracted with EtOAc, the combined organic layers were dried over anhydrous Na₂SO₄, and evaporated under vacuum. The residue was purified by flash column chromatography (hexane–EtOAc) to afford the desired product 3a. 2-Phenyl-5-[(phenylthio)methyl]oxazole (3a) Yellow solid (40.1 mg, 75% yield); mp 43–44 °C. ¹H NMR (500 MHz, CDCl₃): δ = 7.87 (dd, J = 5.9, 2.3 Hz, 2 H), 7.33–7.32 (m, 3 H), 7.30–7.28 (m, 2 H), 7.21–7.18 (m, 2 H), 7.16–7.13 (m, 1 H), 6.76 (s, 1 H), 4.03 (s, 2 H). ¹³C NMR (125 MHz, CDCl₃): δ = 161.5, 148.4, 134.5, 131.3, 130.2, 129.0, 128.6, 127.3, 127.3, 126.1, 125.9, 29.7. LRMS (EI, 70 eV): m/z (%) = 267 (5) [M⁺], 158 (100), 130 (15), 104 (14), 77 (8). ESI-HRMS: m/z calcd for C₁₆H₁₄NOS⁺ [M + H]⁺: 268.0791; found: 286.0794.