Spectroscopic and structural properties of some N-(2-hydroxyethyl)-morpholine derivatives

The 1H, 13C and 15N NMR spectra of N-(2-hydroxyethyl)-morpholine (1), N-(2-hydroxyethyl)-morpholinium chloride (2), N-(2-hydroxyethyl)-morpholine betaine (3), N-morpholinyl-spiro-morpholactone chloride (4) and N-morpholinyl-spiro-morpholactone picrate (5) have been recorded and analyzed. The influence of protonation and N-alkylation of morpholine is discussed. The crystal structures of 4 and 5 have been determined by X-ray diffraction: 4 is orthorhombic, space group Pna21 and 5 is monoclinic, space group P21=c: The structure of 5 is well reproduced by the PM3 and SAM1 methods. q 2004 Elsevier B.V. All rights reserved.