Subrahmanyam, G and Jogibhukta, M (1971) Reaction of benzisoxazolium cations with cyclic β-diketones. In: Tetrahedron, 27 (21). pp. 5229-5237.
reaction.pdf - Published Version
Restricted to Registered users only
Download (659Kb) | Request a copy
Reaction of 2-ethylbenzisoxazolium fluoborate (III) with dimedone, dihydroresorcinol, 2-methyldihydroresorcinol and 2-methylcyclopentane-1,3-dione in the presence of base leads to the formation of amides VIII, XI, X and XIII respectively, via the benzoketoketenimine intermediate (IX) and an intramolecular migration. The 7-hydroxy-2-ethylbenzisoxazolium salt (IV) gives the amide (XIV) by double migration. Amides VIII, XI, X and XIII undergo intramolecular Michael reaction to furnish the benzoxazinones (XVI, XVIII, XVII and XXVI). Stereochemistry of this addition is discussed and the conformation in which the CN bond at C-1′ is attached equatorially to the cyclohexanone ring is assigned to the Spirans (XX, XXX and XXVIII). Effect of acids and bases on the amide (VIII) and the spiran (XVI) is described.
|Item Type:||Journal Article|
|Additional Information:||Copyright of this article belongs to Elsevier Science.|
|Department/Centre:||Division of Chemical Sciences > Organic Chemistry|
|Date Deposited:||11 Jun 2010 08:22|
|Last Modified:||19 Sep 2010 06:08|
Actions (login required)