Preparation of new magnesiated functionalized imidazoles and antipyrines via an iodine-magnesium exchange

Synlett

Volumn , Issue 3, 2000, Pages 345-346

  Dehmel, Florian ^a   Abarbri, Mohamed ^a   Knochel, Paul ^a  

^a UNIVERSITY OF MUNICH   (Germany)

Author keywords

Antipyrines; Functionalized organometallics; Grignard reagents; Imidazoles; Iodine magnesium exchange

Indexed keywords

IMIDAZOLE DERIVATIVE; IODINE; MAGNESIUM; PHENAZONE;

ANALYTIC METHOD; ARTICLE; COMPLEX FORMATION; DERIVATIZATION; DRUG SYNTHESIS; ION EXCHANGE; METHODOLOGY; REACTION ANALYSIS;

EID: 0034007916     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: None     Document Type: Article

References (16)

1. a) Newkome, G. R.; Pandler, W. W. Contemporary Heterocyclic Chemistry, Wiley, New York 1982;
2. b) Gilchrist, T. L. Heterocyclen-Chemie, VCH, Weinheim 1995;
3. Grimmett, M. R. Imidazole and Benzimidazole Synthesis, Academic Press 1997.
4. Boymond, L.; Rottländer, M.; Cahiez, G.; Knochel, P. Angew. Chem. Int. Ed. Engl. 1998, 37, 1701.
5. Rottländer, M.; Boymond, L.; Cahiez, G.; Knochel, P. J. Org. Chem. 1999, 64, 1080.
6. Bérillon, L.; Leprêtre, A.; Turck, A.; Plé, N.; Quéguiner, G.; Cahiez, G., Knochel, P. Synlett 1998, 1359.
7. The iodoimidazole 1 is prepared in two steps starting from 4,5-diiodo-1-ethoxymethyl-2-methylimidazole: (i) i-PrMgBr, THF: NBP (5:1), -30°C, 1 h; (ii) ethyl cyanoformate, -30°C to rt, 8 h; 38% overall yield.
8. a) Knochel, P.; Singer, R. P. Chem. Rev. 1993, 93, 2117,
9. b) Knochel, P.; Perea, J. J. A.; Jones, P. Tetrahedron 1998, 54, 8275.
10. Klement, I.; Rottländer, M.; Tucker, C. E.; Majid, T. N.; Knochel, P.; Venegas, P.; Cahiez, G. Tetrahedron 1996, 52, 7201.
11. The reaction of this immonium salt with various functionalized organometallics will be reported separately : Millot, N.; Piazza, C.; Avolio, S.; Knochel, P. unpublished results.
12. Lipshutz, B. H.; Hagen, W. Tetrahedron Lett. 1992, 33, 5865.
13. 3, DMF, rt, 40h: 98% yield: see Schumacher, R. W.; Davidson, B. S. Tetrahedron 1999, 55, 935.
14. 3, DMF, rt, 40h: 98% yield: see Schumacher, R. W.; Davidson, B. S. Tetrahedron 1999, 55, 935.
15. Hughes, T. V.; Hammond, S. D.; Cava, M. P. J. Org. Chem. 1998, 63, 401.
16. 4) and flash-chromatographical purification (pentane : EtOAc = 1:1) the desired product (3c) was obtained as a colourless oil (156 mg, 67% yield).