ISSN:
1600-5759
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The structures of a 14-crown-4 ether containing both benzo and cyclohexano substituents, 2,6,13,17-tetraoxatricyclo-[16.4.0.07,12]docosa-1(18),19,21-triene, C18H26O4, and its lithium complex, [2,6,13,17-tetraoxatricyclo[16.4.0.07,12]docosa-1(18),19,21-triene-κ4O](thiocyanato-N)lithium(I), [Li(NCS)-(C18H26O4)], are presented. The conformation of the free crown, (I), is not preorganized for cation binding, as its donor dipoles are oriented towards opposite sides of the crown ring. The Li+-crown complex, (II), exhibits two formula units in the asymmetric unit. The binding conformation observed in (II) does not completely reorient the dipoles to one point, resulting in a long Li—O bond length [2.068 (5) and 2.073 (5) Å].
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108270100009033
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