ChemInform Abstract: Site Selectivity in the Addition of Ketoximes to Activated Allenes and Alkynes; N- versus O-Alkylation.

✍ Scribed by Frances Heaney; Bronwyn M. Kelly; Sharon Bourke; Oliver Rooney; Desmond Cunningham; Patrick McArdle

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 30 KB
• Volume: 30
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199921045

✦ Synopsis

In order to examine the formation of N-vinyl nitrones the activated alkyne (II) and allene (VI) are reacted with oximes, e.g. (I). Three groups of products are obtained: the isomeric oximes (III), the stable O-addition products (IV) and the isoxazoline (V). With allene (VI) the reaction proceeds via an O-alkylation to give the O-oxime ethers (VII). In the case of (Ia) the spirocyclic dihydroazepinol (VIII) is obtained whose structure is confirmed by an X-ray analysis. -(HEANEY, FRANCES;