Aldol Reactions between L-Erythrulose Derivatives and Chiral α-Amino and α-Fluoro Aldehydes: Competition between Felkin-Anh and Cornforth Transition States
作者:Santiago Díaz-Oltra、Miguel Carda、Juan Murga、Eva Falomir、J. Alberto Marco
DOI:10.1002/chem.200800956
日期:2008.10.20
Both matched and mismatched diastereoselection have been observed in aldolreactions of a boronenolate of a protected L-erythrulose derivative with several chiral alpha-fluoro and alpha-amino aldehydes. Strict adherence to the Felkin-Anh model for the respective transitionstructures does not account satisfactorily for all the observed results, as previously observed in the case of alpha-oxygenated
Double Diastereoselection in Aldol Reactions Mediated by Dicyclohexylchloroborane between Chiral Aldehydes and a Chiral Ethyl Ketone Derived from <scp>l</scp>-Erythrulose. Synthesis of a C<sub>1</sub>−C<sub>9</sub> Fragment of the Structure of the Antifungal Metabolite Soraphen A<sub>1</sub><sub>α</sub>
作者:Santiago Díaz-Oltra、Juan Murga、Eva Falomir、Miguel Carda、Gabriel Peris、J. Alberto Marco
DOI:10.1021/jo051307p
日期:2005.9.1
diastereoselections have been observed in the aldolreactions of a range of chiral aldehydes with the dicyclohexylboron enolate of a chiralethylketone related to l-erythrulose. As was previously observed in the corresponding aldolreactions with l-erythrulose derivatives, the Felkin−Anh model provides an adequate explanation for the stereochemical outcome of reactions with chiral α-methyl aldehydes. However, a