Heterogeneous Diastereoselective Catalysis--A Powerful Strategy Toward C(15) Stereoselectivity from PGF2α Analogues
Simona M Coman, Vasile I Parvulescu1
1Department of Organic Chemistry, Biochemistry and Catalysis, Faculty of Chemistry, University of Bucharest, Bdul Regina Elisabeta, 4-12, Bucharest 030016, Romania. vasile.parvulescu@g.unibuc.ro.
Abstract:
A major trend in fine chemicals and pharmaceuticals is the synthesis of molecules with increased complexity. This trend translates the aim of organic syntheses to conditions in which high degrees of chemo-, regio- and stereoselectivity can be provided. In this context, the chemoselective hydrogenation of one functional group in the presence of other reactive groups is a frequently encountered problem in fine chemicals manufacture. This study provides a critical analysis including elegant examples of reactions in which high chemo- and diastereoselectivities were achieved in the hydrogenation of a C=O group in the presence of C=C double bond. A particular emphasis is addressed to the stereoselective C(15) synthesis from Cloprostenol--a PGF2α structural analogue.
Related Concept Videos
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Prochirality
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Regioselectivity and Stereochemistry of Hydroboration
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.


