Stereoselective synthesis of (1 R,3 R,4 R)-3-(1,2,4-triazolo[4,3- x]azin-3-yl)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ones

• Published in: Tetrahedron: asymmetry Vol. 13; no. 8; pp. 821 - 833
• Main Authors: Grošelj, Uroš, Rečnik, Simon, Svete, Jurij, Meden, Anton, Stanovnik, Branko
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15-05-2002
• ISSN: 0957-4166; 1362-511X
• DOI: 10.1016/S0957-4166(02)00208-2

(1
R,3
R,4
R)-3-(1,2,4-Triazolo[4,3-
x]azin-3-yl)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-ones were prepared in 68–94% d.e. in three steps from (1
R)-(+)-camphor via coupling of (1
R,4
R)-3-[(
E)-(dimethylamino)methylidene]-1,7,7-trimethylbicyclo[2.2.1]heptan-2-one with hydrazinoazines followed by oxidative cyclisation of the intermediate hydrazones with methanolic bromine. The structures were determined by 2D NMR techniques and NOESY spectroscopy as well as by X-ray diffraction.
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