The temperature-sensitive monomer, acrylamido-4-(2-aminoethyl)morpholine (C9H16N2O2), has been synthesized and its crystal structure has been investigated by X-ray analysis and PM3 method. The compound crystallizes in monoclinic space group P2(1)/c with a = 4.830(1), b = 23.940(3), c = 9.048(2) Angstrom, beta = 91.35(2)degrees, V = 1045.9(3) Angstrom(3), Z = 4, and D-calc = 1.17 mg m(-3). The title structure was solved by direct methods and refined to R = 0.0542 for 1834 reflections by full-matrix anisotropic least-squares methods. The conformational study was carried out using PM3 semi-empirical method while rotating the torsion angle [N1-C1-C2-O1] in 10degrees steps. (C) 2002 Elsevier Science BN. All rights reserved.