Highly Regio- and stereoselective formation of 2-hydroxy-5,6-dihydro-2H-1,4-oxazines. An X-ray and 13C NMR study
作者:Aurelio Ortiz、Norberto Farfán、Rosa Santillan、María de Jesus Rosales、Efrén García-Baéz、Jean Claude Daran、Sabine Halut
DOI:10.1016/0957-4166(95)00361-r
日期:1995.11
(-)-Norephedrine and (-)-norpseudoephedrine undergo condensation with a wide variety of 1,2-diketones to yield;the corresponding 2-hydroxy-5,6-dihydro-2H-1,4-oxazines with high regio- and stereoselectivity. The X-ray structure analysis of five of the compounds studied shows that the stereochemistry at the newly formed stereogenic center is S in all cases.