Abstract
The title 1,4-piperazine-2,5-dione was synthesized in 23% yield over six steps from ethyl 2-amino-4,7-dimethoxyindan-2-carboxylate. Crystallization by slow diffusion of ether into a chloroform solution and by slow evaporation of an ethanol-chloroform-benzene solution produced polymorphic crystalline forms as determined by single-crystal X-ray analysis. The polymorphs exhibited different hydrogen-bonding networks. The association of this piperazinedione in solution was studied using mass spectrometric and nuclear magnetic resonance spectroscopic techniques. The MS and NMR data were interpreted using the solid-state structures as models for solution aggregation. Association constants extracted from the NMR data are in line with those of other cyclic cis amides in chloroform solvent.
Original language | English (US) |
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Pages (from-to) | 8693-8702 |
Number of pages | 10 |
Journal | Journal of Organic Chemistry |
Volume | 70 |
Issue number | 22 |
DOIs | |
State | Published - Oct 28 2005 |
ASJC Scopus subject areas
- Organic Chemistry