Proline-calixarene thiourea host-guest complex catalyzed enantioselective aldol reactions: from nonpolar solvents to the presence of water

Date

2014-03-15

Author

Demircan, Ezgi
EYMUR, SERKAN
Demir, Ayhan Sıtkı

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A proline-calix[4]arene thiourea host-guest complex catalyzed intermolecular aldol reaction of aromatic aldehydes with cyclohexanone has been developed. The anti-configured products were obtained in good yields and with high enantioselectivities. The reaction is proposed to work via a modified Houk-List model, where the carboxylate part of the praline constitutes as a supramolecular system with the thiourea. The outcome of the study indicates the influence of the calix[4]arene thiourea on both the reactivity and selectivity in a non-polar reaction medium, even in the presence of water at moderate temperatures.

Subject Keywords

Asymmetric aldol, Transition states, Organic reactions, Amino acid, Organocatalysts, Aldehydes, Additives, Origin

URI

https://hdl.handle.net/11511/56396

Journal

TETRAHEDRON-ASYMMETRY

DOI

https://doi.org/10.1016/j.tetasy.2014.01.015

Collections

Department of Chemistry, Article

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Citation Formats

E. Demircan, S. EYMUR, and A. S. Demir, “Proline-calixarene thiourea host-guest complex catalyzed enantioselective aldol reactions: from nonpolar solvents to the presence of water,” TETRAHEDRON-ASYMMETRY, pp. 443–448, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56396.