In our synthetic organic chemistry projects, we aim to demonstrate the utility of catalytic methodologies by incorporating them in at least one of the key steps. In earlier years, we did this by employing/modifying established methodologies reported by others. We have started to employ our own catalytic methodologies for the synthesis of biologically interesting molecules. Selected publications are listed below:

Projects on (Catalytic) Organic Synthesis

A Concise Asymmetric Synthesis of Torcetrapib”, M. Guino, P. H. Phua, J-C. Caille and K. K. Hii, J. Org. Chem., 2007, 72, 6290-6293.

doi:10.1021/jo071031g

Abstract: Optically active torcetrapib was synthesized in seven steps from achiral precursors without the need for protecting groups, utilizing an enantioselective aza-Michael reaction to achieve asymmetry.

Delineating Ligand Effects in Intramolecular Aryl Amidation Reactions: Formation of a Novel Spiro-Heterocycle by a Tandem Cyclisation Process

E. L. Cropper, A. P. Yuen, A. J. P. White, A. Ford and K. K. Hii, Tetrahedron, 2008, 695, 525.

doi:10.1016/j.tet.2008.10.098

Abstract: Ligand effects for intramolecular Pd-catalysed aryl amidation reaction were examined for the synthesis of 7-membered benzolactam rings. In an attempt to produce an 8-membered ring, tandem C-N/C-O bond forming reactions occurred to give a novel spiro-benzofuran-lactam structure.

Asymmetric synthesis of 2-alkyl-substituted tetrahydroquinolines by an enantioselective aza-Michael reaction

L. L. Taylor, F. W. Goldberg and K. K. Hii, Org. Biomol. Chem, 2012, 10, 4424.

DOI: 10.1039/c2ob25122a

Abstract: An optically active tetrahydroquinoline intermediate was prepared in 8 steps from monoprotected ethylene glycol, using a Pd-catalysed aza-Michael reaction to induce chirality. This can be transformed into three Galipea alkaloids (angustureine, galipeine and cuspareine).

 

Asymmetric synthesis and structural analysis of levonantradol

A. E. Sheshenev, E. V. Boltukhina and K. K. Hii, Chem. Commun., 2013, 49, 3685.

DOI: 10.1039/c3cc41388h

Abstract: The first asymmetric synthesis of a synthetic cannabinoid levonantradol was accomplished, and the 3-D solution structure of its core architecture was confirmed by NMR and computational methods.