Journal zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA of M olecular Structure, 249 (1991) 127-133 Elsevier Science Publishers B.V., Amsterdam 127 zyxwvutsrqpon Crystal structure and 35C1 NQR of ( 2 ) /3- (trichloromethyl ) -P-propiolactone Reha Basaran, Shi-qi Dou and Alarich Weiss Znstitut fiir Physikalische Chemie, Physikalische Chemie ZZZ, Technische Hochschule Darmstadt, Petersen&r. 20, D-6100 Darmstadt (Germany) (Received 20 March 1991) zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFED Abstract The crystal structure of ( f ) /I- (trichloromethyl)-/-propiolactone, CIH,C1,02, is reported (T=294 K); space group C&P2,/c, a=lOOZ(l) pm, b=565.0(5) pm, c=1225(1) pm, ~=93.97(3)“,2=4, V=691.85(2) ~lO”pm~.AweakhydrogenbondisobservedbetweenH(C(3)) and the carbonyl oxygen 0 (2). The 35Cl NQR spectrum shows three lines in the range 771 T(K) 1310. At 77 K the resonance frequencies are observed at 39.822(5) MHz, 38.905(5) MHz and 38.322(5) MHz. INTRODUCTION The trichloromethyl group is interesting with respect to its dynamical be- haviour. Quite often the onset of order-disorder (dynamic or static), different orientations of the CC& group with respect to the rest of the molecule, is ob- served by studying the temperature dependence of the 35C1 NQR spectrum of molecules incorporating CC&. Most extensively investigated in this respect are molecular compounds and salts of the trichloroacetic acid (see for example ref. 1) . In connection with this work we are interested in the structure and dynamic behaviour of Ccl3 groups in organic molecules, which may or may not form hydrogen bonds, in order to study the influence of such intermolecular inter- actions on the dynamics of the -Ccl3 group. j?- (trichloromethyl ) -P-propiolactone was in recent years studied rather in- tensively, particularly with respect to developing methods for the stereospe- cific synthesis of the compound [ 2-41. In this paper we report on the crystal structure of the racemic compound ( + ) /I- (trichloromethyl) -/%propiolactone (3-hydroxy-4,4,4-trichlorobutyric acid-glactone, 4- (trichloromethyl)-2-oxe- tanone), C4H3C1302, and on its 35Cl nuclear quadrupole resonance (NQR) spectrum. 0022-2860/91/$03.50 0 1991 Elsevier Science Publishers B.V. All rights reserved.