1,4-Oxazines, 1,4-benzoxazines and reduced forms

This chapter deals with the new chemistry that is exemplified on the use of morpholines as enamine precursors. A very large literature relating to the medicinal and industrial applications of morpholine derivatives is not covered in this chapter. The review of 1, 4-oxazinones describes the presence of the halogen substituent at C-5 seems important, and the addition occurs with both electron-rich and electron-poor alkenes. For symmetrically substituted alkenes there is preference for formation of the endo configured adducts. As an illustration, the chiral morpholines are available through the intermolecular cyclisation of allylic amines. Here the reactions are mediated by palladium and can be made catalytic by adding a small amount of trifluoroacetic acid to the reagent system. The reactions of morpholines are explained with structure diagrams, equations and examples. The synthesis, reactions and derivatives of the compounds containing phenoxazines and phenoxazinones are presented.