The first enzymatic resolution of quaternary alpha-acetoxy alpha-substituted cyclic ketones

Date

2006-04-03

Author

Tanyeli, Cihangir
İYİGÜN, Cigdem

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

95
views

0
downloads

The enantioselective resolution of quaternary alpha-acetoxy alpha-substituted indanone and 1-tetralone derivatives was performed with commercially available enzyme CRL in pH = 8.0 phosphate buffer. Various parameters that would affect the enantoselectivities were tested, and the optimal enzymatic resolution condition was found to afford the enantiomerically enriched quaternary acetoxylated substrates with high ees (varied between 81% and 85%).

Subject Keywords

Physical and Theoretical Chemistry, Inorganic Chemistry, Organic Chemistry, Catalysis

URI

https://hdl.handle.net/11511/47627

Journal

TETRAHEDRON-ASYMMETRY

DOI

https://doi.org/10.1016/j.tetasy.2006.04.012

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

The first enzymatic resolution of quaternary alpha '-acetoxy alpha,beta-unsaturated cyclohexenones and cyclopentenones Tanyeli, Cihangir; Iyigun, CEM (Elsevier BV, 2005-12-12) The enantio selective resolution of various quaternary alpha'-acetoxy alpha,beta-unsaturated cyclohexenones and cyclopentenones was performed with the commercially available enzyme CCL in pH = 8.0 phosphate buffer. Various parameters that would affect the enantioselectivities were tested and the best enzymatic resolution conditions were found to afford the enantiomerically enriched quaternary acetoxylated substrates with high ee varying between 36% and 99%.
An asymmetric synthesis of both enantiomers of 2,2,2-trifluoro-1-furan-2-yl-ethylamine and 3,3,3-trifluoroalanine from 2,2,2-trifluoro-1-furan-2-yl-ethanone Demir, Ayhan Sıtkı; Sesenoglu, O; Gercek-Arkin, Z (Elsevier BV, 2001-09-13) The selective conversion of 2,2,2-trifluoro-1-furan-2-yl-ethanone into (E)- and (Z)-oximes and oxime ethers and subsequent oxazaborolidine-catalyzed enantioselective reduction using different amino alcohols furnished both enantiomers of the important chiral building block 2,2,2-trifluoro-1-furan-2-yl-ethylamine with e.e. of up to 88%. Oxidation of the furan ring afforded both enantiomers of 3,3,3-trifluoroalanine in 91-93% yields.
A new and efficient chemoenzymatic route to both enantiomers of alpha '-acetoxy-alpha-methyl and gamma-hydroxy-alpha-methyl cyclic enones Demir, Ayhan Sıtkı; Findik, H; Kose, E (Elsevier BV, 2004-03-08) A chemoenzymatic synthesis of both enantiomers of the pharmacologically interesting alpha'-acetoxy-alpha-methyl and gamma-hydroxy-alpha-methyl cyclic enones starting from alpha-methyl-beta-methoxy cyclic enones is reported. Manganese(Ill) acetate-mediated acetoxylation followed by the enzyme-mediated hydrolysis of alpha'-acetoxy enone provides acetoxy enones 1a and 2a and hydroxy enones 1b and 2b with high enantiomeric excesses in good yields. The reduction of the acetoxy and hydroxy enones furnished both e...
A new and efficient chemoenzymatic route to both enantiomers of alpha '-acetoxy and alpha '-hydroxy-alpha-methoxy cyclic enones Demir, Ayhan Sıtkı; Caliskan, Z; Aydin, AE; Bicer, I (Elsevier BV, 2006-03-06) A chemoenzymatic synthesis of both enantiomers of the pharmacologically interesting alpha'-acetoxy and alpha'-hydroxy-alpha-methoxy cyclic enones starting from alpha-hydroxy cyclic enones is described. Protection of 1,2-diketones, manganese(III) acetate-mediated acetoxylation followed by enzyme-mediated hydrolysis of alpha'-acetoxy enones gives acetoxy enones 3a-d and hydroxy enones 4a-d with high enantiomeric excesses (up to 99%) and good yields. The transesterification of rac-4b in the presence of DMAP af...
Novel enantioselective synthesis of both enantiomers of furan-2-yl Amines and amino acids Demir, Ayhan Sıtkı; Sesemoglu, O; Ulku, D; Arici, C (Wiley, 2003-01-01) A new enantioselective synthesis of furan-2-yl amines and amino acids is described, in which the key step is the oxazaborolidine-catalyzed enantioselective reduction of O-benzyl (E)- and (Z)-furan-2-yl ketone oximes to the corresponding chiral amines. The chirality of the furan-2-yl amines is fully controlled by the appropriate choice of the geometrical isomer of the O-benzyl oxime. Oxidation of the furan ring furnished amino acids in high yields.

Citation Formats

C. Tanyeli and C. İYİGÜN, “The first enzymatic resolution of quaternary alpha-acetoxy alpha-substituted cyclic ketones,” TETRAHEDRON-ASYMMETRY, pp. 1125–1128, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47627.