Twofold ring cleavage of 2,3,5,6-tetrahydro-10bH-oxazolo[2,3-a]isoquinoline with salts of hydroxylamine derivatives

Contrary to literature the reaction of the cyclic carbinolamine ether 1 with hydroxylamine hydrochloride don't give the N-hydroxyaminal hydrochloride 2 . HCl, but the ring opened E-oxime amine hydrochloride 3 . HCl. The structure is proved with NMR- and UV-spectroscopic methods. Similar products 11 . HCl - 15 . HCl and 18 . HCl/19 . HCl are available from salts of hydroxylamine ethers and semicarbazides. The reactivity of 1 and the stability of the products are investigated.