Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives

2006-01-23
ÖZDEMİRHAN, FAZİLET DEVRİM
ÇELİK, MURAT
ATLI, SELİN
Tanyeli, Cihangir
Racemic alpha'-acetoxy alpha,beta-unsaturated cyclopentanone and cyclohexanone have been resolved into the corresponding enantiomerically enriched alpha'-hydroxylated and acetoxylated compounds with 96-97% ee via PLE hydrolysis. Stereoselectivity in the palladium(II)-catalyzed reaction between the enantiomerically enriched alpha'-acetoxylated compounds and diazomethane has been investigated. In the alpha'-acetoxylated cyclopentenone, preferential cyclopropanation occurs in the anti-form, whereas alpha'-acetoxylated cyclohexenone affords both syn- and anti-products (syn:anti, 61:36%). The relative configuration of the products was determined by NOE experiments.
TETRAHEDRON-ASYMMETRY

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Citation Formats
F. D. ÖZDEMİRHAN, M. ÇELİK, S. ATLI, and C. Tanyeli, “Chemoenzymatic synthesis of enantiomerically enriched 2-oxobicyclo[m.1.0]alkan-3-yl acetate derivatives,” TETRAHEDRON-ASYMMETRY, pp. 287–291, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40329.