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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Hydrogen-bonded layered structures in two bis(tert-butyldimethylsilyloxy)-substituted cyclic diol derivatives
C Foces-Foces1, M López-Rodríguez
1Instituto Rocasolano, CSIC, Departamento de Cristalografía, Madrid, Spain. cfoces@iqfr.csic.es
Abstract:
2,6-Bis(tert-butyldimethylsilyloxy)-9-oxabicyclo[3.3.1]nonane-3,7-diol, C(20)H(42)O(5)Si(2), (I), and 4,8-bis(tert-butyldimethylsilyloxy)-2,6-dioxatricyclo[3.3.1(3,7)]decane-1,3-diol, C(20)H(40)O(6)Si(2), (II), form layered structures that differ in the way the molecules are connected within each layer. The endocyclic O atom common to both structures plays an active role in the hydrogen-bonding network, whereas the second oxygen bridge in (II) does not participate in any interaction. This work reports the first structural analysis of two bis(tert-butyldimethylsilyloxy)-substituted cyclic diol derivatives and provides insight into the influence of small changes in the molecular structure on the supramolecular aggregation. The unbalanced hydrogen-bond acceptor/donor ratio, greater in (II) than in (I), does not result in the inclusion of water molecules in the structure.
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