863868-80-8Relevant articles and documents
Structural optimization of thiourea-based bifunctional organocatalysts for the highly enantioselective dynamic kinetic resolution of azlactones
Berkessel, Albrecht,Mukherjee, Santanu,Mueller, Thomas N.,Cleemann, Felix,Roland, Katrin,Brandenburg, Marc,Neudoerfl, Joerg-M.,Lex, Johann
, p. 4319 - 4330 (2008/09/18)
This article describes the synthesis of a library of structurally diverse bifunctional organocatalysts bearing both a quasi-Lewis acidic (thio)urea moiety and a Bronsted basic tertiary amine group. Sequential modification of the modular catalyst structure and subsequent screening of the compounds in the alcoholytic dynamic kinetic resolution (DKR) of azlactones revealed valuable structure-activity relationships. In particular, a "hit-structure" was identified which provides e.g. N-benzoyl-tert-leucine allyl ester in an excellent enantiomeric excess of 95%. The Royal Society of Chemistry 2006.