129764-21-2Relevant academic research and scientific papers
Synthesis and self-aggregation of enantiopure and racemic molecular tweezers based on the bicyclo[3.3.1]nonane framework
Wallentin, Carl-Johan,Wixe, Torbjoern,Wendt, Ola F.,Bergquist, Karl-Erik,Waernmark, Kenneth
scheme or table, p. 3994 - 4002 (2010/07/04)
A pair of molecular tweezers (syn-4) that consists of quinoline and pyrazine units fused to a bicyclic framework is presented. The tweezers were synthesised both as a racemic mixture (rac-4) and an enantiomerically pure form ((R,R,R,R)-4) starting from either racemic or enantiomerically pure bicyclo[3.3.1]nonane-2,6dione (3). Homochiral dimers were ob-served in the solid state for rac-A. The self-association of both rac-4 and (R,R,R,R)-4 was studied in solution. A weak self-association constant in CDCl3 was estimated by 1H NMR spectroscopic dilution titration experiments in both cases, following several proton resonances. For this purpose, a general normalisation model for the accurate determination of association constants from multiple datasets was developed. In contrast to the solid state, no diastereomeric discrimination was observed for rac-4 in solution.
Molecular clefts 2. An analogue of Kagan's ether as a molecular cleft: Synthesis and clathrate formation with ethyl acetate
Harmata, Michael,Barnes, Charles L.
, p. 1825 - 1828 (2007/10/02)
A convenient synthesis of 5α,8α, 14α, 17α-5,6,8,9,14,15,17,18 - octahydro-5,17:8,14-diepoxydibenzo[e,e′]benzo[1,2-a:4,5-a′ dicyclooctene (2) is described. This molecular cleft represents the parent of a new class of chiral molecular tweezers. It forms a clathrate with ethyl acetate which is stable even after 12 hours at 0.1 Tort. The structure of 2 was established by spectral and X-ray data. A convenient synthesis of 5a,8a,14a,17a-5,6,8,9,14,15,17,18-octahydro-5,17:8,14-diepoxydibenzo[e, e′]benzo[1,2-a:4,5-a′]icyclooctene (2) is described. It forms a clathrate with ethyl acetate which is stable even after 12 hours at .1 Torr. (Chemical Equation Presented).
