Asymmetric baker's yeast reductions of bridgehead-substituted bicyclo[2.2.2]octane-2,6-dione derivatives followed by conversion into catalytically active BODOLs for the diethylzinc addition to benzaldehyde

Summary, in English

4-Substituted bicyclo[2.2.2]octane-2,6-diones have been synthesized and tested as substrates in the enantioselective reduction with baker's yeast to give the corresponding hydroxy ketones. It was found that the derivative bearing a TIPSO group at the 4-position was not reduced at all while that with a TBDMSO group gave 87% yield and 46% ee. Other 4-oxy functionalized derivatives were reduced with varying yields (36-87%) and ees (10-82%). The best result was obtained for the 4-Oallyl derivative (80% yield, 82% ee). The hydroxy ketones carrying the benzyloxy and allyloxy groups at the 4-position were converted into the corresponding BODOLs, which were tested as catalysts in the diethylzinc addition to benzaldehyde. In this reaction the ees were 90% and 89%, respectively, which showed that BODOLs substituted at the 4-position are essentially as good catalysts in this reaction as those bearing a hydrogen. (C) 2010 Elsevier Ltd. All rights reserved.

• Author: Sophie Manner; Cecilia Hansson; Johanna Larsson; Viveca Oltner; Torbjörn Frejd
• Department/s: Centre for Analysis and Synthesis
• Publishing year: 2010
• Language: English
• Pages: 1374-1381
• Publication/Series: Tetrahedron: Asymmetry
• Volume: 21
• Issue: 11-12
• Links: http://dx.doi.org/10.1016/j.tetasy.2010.06.003
• Document type: Journal article
• Publisher: Elsevier
• Topic: Organic Chemistry
• Status: Published
• ISBN/ISSN/Other: ISSN: 0957-4166