Crystal structure of 5-(l-menthyloxy)-3-chloro-4-pyrrolidinyl-2(5H)-furanone

The molecular structure of the title compound 5-(l-menthyloxy)-3-chloro-4-pyrrolidinyl-2(5H)-furanone , C18H28ClNO3( I) , has been determined by Xray diffraction at 296(1)K. The crystal is monoclinic with space group P2(1), a = 9. 457 (3), b = 10. 413(3), c = 9. 525(2) Angstrom , beta = 95. 19(2)degrees, V = 934(1) Angstrom(3) , Z = 2 , M-r 341. 88, D-x = 1. 22 g/cm(3), mu = 2. 15 cm(-1), F(000) = 368. The final R factor is 0. 059, and R-w is 0. 065 for 1020 observed reflections with I greater than or equal to 3 sigma(I). The absolute configuration at C(14) of the acetal carbon was proved to be SI taking into account the known configuration of 1R, 2S, 5R-menthyl moiety. There are three rings in the molecule of this compound: the furanone ring, the pyrrolidine ring and the mentholoxy group ring. The franone ring is connected with the pyrrolidine ring and the mentholoxy ring by N atom and mu(2)-O bridge atom respectively.