Direct synthesis of Weinreb amides from carboxylic acids using triphosgene

Letters in Organic Chemistry

Volumn 4, Issue 1, 2007, Pages 20-22

  Han, Ki Jong ^a   Kim, Misoo ^b  

^a Ajou University   (South Korea)

^b Hankyong National University   (South Korea)

Author keywords

Carboxylic acids; N,O dimethylhydroxylamine hydrochloride; Triphosgene; Weinreb amides

Indexed keywords

EID: 33947131589     PISSN: 15701786     EISSN: None     Source Type: Journal    
DOI: 10.2174/157017807780037441     Document Type: Article

References (20)

1. Nahm S.; Weinreb, S. M. Tetrahedron Lett., 1981, 22, 3815.
2. For some reviews concerning the synthesis of Weinreb amides, See: a) Sibi, M. P. Org. Prep. Proced. Int., 1993, 25, 15;
3. b) Mentzel, M.; Hoffmann, H. M. R. J. Prakt. Chem., 1997, 339, 517;
4. c) Singh, J.; Satyamurthi, N.; Aidhen, I. S. J. Prakt. Chem., 2000, 342, 340.
5. a) Tunoori, A. R.; White J. M.; Georg, G. I. Org. Lett., 2000, 2, 4091;
6. b) Luca, L. D.; Giacomelli, G.; Taddei, M. J. Org. Chem., 2001, 66, 2534;
7. c) Bailén, M. A.; Chinchilla, R.; Dodsworth, D. J.; Nájera, C. Tetrahedron Lett., 2001, 42, 5013;
8. d) Banwell, M.; Smith, J. Synth. Commun., 2001, 31, 2011;
9. e) Kim, M.; Lee, H.; Han, K.-J.; Kay, K.-Y. Synth. Commun., 2003, 33, 4013;
10. f) Hioki, K.; Kobayashi, H.; Ohkihara, R.; Tani, S.; Kunishima, M. Chem. Pharm. Bull., 2004, 52, 470;
11. g) Lee, H.; Kim, M.; Han, K.-J. Kr. Pat. 2005, 032135;
12. h) Han, K.-J.; Lee, H.; Kim, M. Kr. Pat. 2005, 112690.
13. a) Cotarca, L.; Delogu, P.; Nardelli, A.; Sunjić, V. Synthesis, 1996, 553, and references therein;
14. b) Ghosez, L.; George-Koch, I.; Patiny, L.; Houtekie, M.; Bovy, P.; Nshimyumukiza, P.; Phan, T. Tetrahedron, 1998, 54, 9207;
15. c) Flosser, D. A.; Olofson, R. A. Tetrahedron Lett., 2002, 43, 4275;
16. d) Banwell, M. G.; Coster, M. J.; Harvey, M. J.; Monies, J. J. Org. Chem., 2003, 68, 613.
17. a) Gumaste, V. K.; Bhawal, B. M.; Deshmukh, A. R. A. S. Tetrahedron Lett., 2002, 43, 1345;
18. b) Kotz, R.; Roestemadji, J.; Mobashery, S. J. Org. Chem., 1994, 59, 2913.
19. 2 (10 ml) at 0 °C were added triphosgene (1 mmol) and triethylamine (10 mmol). Then N,O-dimethylhydroxylamine hydrochloride (2 mmol) was added to the solution and the ice bath was removed. The reaction mixture was stirred at room temperature until disappearance of the acid, as determined using TLC. After completion, the triethylamine hydrochloride was removed by suction filtration. Removal of the filtrate by rotary evaporation followed by short path silica gel column chromatography purification using 20% ethyl acetate in hexane as the mobile phase afforded the pure product.
20. 5): 200.0433, found 200.0426 [M].