A convenient synthesis of pyridine and 2,2′-bipyridine derivatives

TETRAHEDRON

卷:65

Article

Altuna-Urquijo, Marta¹  Gehre, Alexander¹  Stanforth, Stephen P.¹  Tarbit, Brian² 

[1] Northumbria Univ, Sch Appl Sci, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England

[2] Vertellus Special UK Ltd, Middlesbrough TS2 1UB, Cleveland, England

关键词: Pyridines;    2,2 '-Bipyridines;    1,2,4-Triazines;    alpha,beta-Diketo-esters;    Aza Diels-Alder reaction;   

DOI  :  10.1016/j.tet.2008.11.090

来源: Elsevier

【 摘 要 】

alpha-Chloro-alpha-acetoxy-beta-keto-esters 9 were readily prepared from beta-keto-esters 6 in good overall yields. These compounds reacted as alpha,beta-diketo-ester equivalents 2 with amidrazones 1 yielding triazines 3, generally in good yields. Picolinates 10 provided an alternative source of alpha,beta-diketo-ester equivalents 2 when treated with copper(II) acetate. A 'one-pot' reaction of the alpha,beta-diketo-ester equivalents 2 with amidrazones 1 in the presence of 2,5-norbornadiene 5 in boiling ethanol yielded the pyridines 4 and 2,2'-bipyridines 4 (R-1=2-pyridyl) directly without the need to isolate the corresponding triazines 3. Triazine 3c reacted with the aza-dienophiles 13 and 17 affording the products 16 and 18, respectively, in good yields. (C) 2008 Elsevier Ltd. All rights reserved.

【 授权许可】

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