97097-52-4Relevant academic research and scientific papers
Role of cations and confinement in asymmetric photochemistry: Enantio- and diastereo-selective photocyclization of tropolone derivatives within zeolites
Joy, Abraham,Kaanumalle, Lakshmi S.,Ramamurthy
, p. 3045 - 3053 (2007/10/03)
Asymmetric induction in photochemical reactions has been explored using the photochemistry of tropolones as a model. Three approaches have been examined: chiral inductor, chiral auxiliary and [chiral inductor + chiral auxiliary]. All three methods gave excellent asymmetric induction in zeolite and very little or zero induction in solution. Results presented on tropolones clearly illustrate the remarkable influence that a confined space studded with cations can have on asymmetric induction. Tropolone derivatives, upon irradiation undergo 4π-electron electrocyclization to yield a bicyclic product and a rearranged product. Enantiomeric excess up to 68% has been achieved in the cyclized product. In systems where a chiral inductor has been covalently linked, diastereomeric excess as high as 88% has been achieved within a zeolite while the same system in solution gave 10%. The Royal Society of Chemistry 2005.
Asymmetric induction with cyclodextrins: Photocyclization of tropolone alkyl ethers
Koodanjeri, Smriti,Joy, Abraham,Ramamurthy
, p. 7003 - 7009 (2007/10/03)
Employing the photobehavior of tropolone alkyl ethers as the probe, we have established that cyclodextrins could as a serve as medium to bring about enantioselective photoreactions. The enantioselectivity observed in this study is moderate at best. The enantioselectivity observed in the solid state in comparison to aqueous solution suggests that a rigid environment may be essential to achieve chiral induction during photoreactions of organic molecules. In this context the much higher enantioselectivity observed for the same systems within zeolites is noteworthy. (C) 2000 Elsevier Science Ltd.
A CONVENIENT ROUTE TO TROPOLONE ETHERS
Bass, R. J.,Gordon, D. W.
, p. 225 - 228 (2007/10/02)
A general synthesis of tropolone ethers employing the reaction of tropolone with potassium carbonate, an alkyl halide and dicyclohexyl-18-crown-6 in acetonitrile solvent is described.
