STUDIES ON CROWN-ETHER COMPLEXES .31. SYNTHESIS, PROPERTIES AND STRUCTURE OF THE COMPLEXES OF LIGHTER LANTHANIDE NITRATES WITH 3-DIPHENYL-1,4,7,10,13-PENTAOXACYCLOPENTADEC-2-ENE (STILBENO-15-CROWN-5)

Complexes of the lighter lanthanide nitrates with stilbeno-15-crown-5 (L) have been prepared in ethyl acetate. These new complexes with the general formula Ln(NO3)3.L.H2O (Ln = La, Ce, Pr, Nd) have been charact erized by means of elemental analyses, i.r. spectra, H-1 n.m.r. spectr a and conductivity measurements. The crystal structure of La(NO3)3.L h as been determined by X-ray methods, and refined to a residual R 0-051 3 for 4937 independent reflections with I greater-than-or-equal-to 1.5 sigma(I). It crystallizes in the monoclinic space group P2(1)/a with a 16.090(5), b 15.654(8), c 22.687(2) angstrom, beta 93-96(4)-degrees, V 5700(4) angstrom3, and Z 8. There are two independent La(NO3)3.L mon omers in one asymmetric unit; in each the coordination number is 11.