90786-14-4Relevant academic research and scientific papers
NEW PROTOTROPIC PROCESSES IN THE SYNTHESIS OF HETEROCYCLIC COMPOUNDS
Grigg, R.
, p. 593 - 604 (2007/10/02)
X=Y-ZH systems are considered in general terms and divided into four classes according to the number of constituent atoms that possess lone pair electrons.Those systems in which the central Y atom possesses a lone pair are shown to be capable of participa
X=Y-ZH Systems as Potential 1,3-Dipoles. Part 3. Isoxazolidines from the 1:1 Cycloaddition of Oximes with Dipolarophiles
Grigg, Ronald,Thianpantangul, Sunit
, p. 653 - 656 (2007/10/02)
The 2-oximes of 1,2,3-tricarbonyl systems undergo cycloaddition to N-phenylmaleimide to give isoxazolidines.Proton transfer from oxygen to nitrogen, possible via an intramolecular 1,5-H shift, is believed to generate a 1,3-dipole as the reactive intermediate.The products are 1:1 adducts in contrast to the cycloadducts of simple aldehyde oximes and ketone oximes which incorporate a second molecule of dipolarophile on the isoxazolidine N-atom.Attempts to extend the cycloaddition to several other electronegative olefins were unsuccessful, whilst dihydropyran gave Michael adducts.
