Synthesis,crystal and molecular structures of 1,8-diaza-11,14-dioxacyclohexadeca-2,7-dione and 1,10-diaza-4,7-dioxacyclohexadeca-2,9-dione |
| |
Authors: | P Gluziński S Kasprzyk J W Krajewski P Sałański T Stankiewicz J Jurczak |
| |
Institution: | (1) Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warszawa, Poland |
| |
Abstract: | 1,8-Diaza-11,14-dioxacyclohexadeca-2,7-dione (3) has been synthesized under high-pressure conditions, whereas 1,10-diaza-4,7-dioxacyclohexadeca-2,9-dione (6) has been obtained under thermal conditions. Both compounds have been investigated in the solid state and in solution by X-ray structural and NMR methods, respectively. The crystals of3 are orthorhombic, space groupPbca; the crystals of6 are triclinic, space groupP¯1. Both structures were solved by direct methods, and refined by a full-matrix, least-squares procedure giving for3
R=0.045 and for 6R=0.056 (R
w
=0.065). From the NMR investigations in solution a twofold symmetry of both molecules (probably in intermediate conformations) is suggested; no such symmetry was found in crystalline state. The structure of6 exhibits a positional disorder of one O-heteroatoms with the population ratio 0.51 0.49. The arrangement of the macroring with respect to the carbonyl groups was found to betransoid in3 andcisoid in6. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|