Catalytic Enantioselective Alkylation of Substituted Dioxanone Enol Ethers: Ready Access to C(α)-Tetrasubstituted Hydroxyketones, Acids, and Esters
作者:Masaki Seto、Jennifer L. Roizen、Brian M. Stoltz
DOI:10.1002/anie.200801424
日期:2008.8.25
The catalytic enantioselective formation of tetrasubstituted α-alkoxycarbonyl compounds is an ongoing challenge to synthetic chemists.[1] Fully-substituted α-hydroxyesters and acids comprise essential components of, and building blocks for, many bioactive natural products. These include quinic acid (1), cytotoxic leiodolide A (2),[2] and the anti-cancer agents in the harringtonine series (3a–f), whose activities depend dramatically on the presence and composition of an α-hydroxyester side-chain.[3] While many approaches to these important moieties exist,[4,5] we envisioned applying our recently developed palladium-catalyzed methods for the formation of enantioenriched all-carbon quaternary stereocenters in cyclic alkanones[6] to a general synthesis of C(α)-tetrasubstituted hydroxy carbonyl compounds.[7]
MOORLAG, HENK;KRUIZINGA, WIM H.;KELLOGG, RICHARD M., REC TRAV. CHIM. PAYS-BAS., 109,(1990) N, C. 479-480
作者:MOORLAG, HENK、KRUIZINGA, WIM H.、KELLOGG, RICHARD M.
作者:Douglas C. Behenna、Justin T. Mohr、Nathaniel H. Sherden、Smaranda C. Marinescu、Andrew M. Harned、Kousuke Tani、Masaki Seto、Sandy Ma、Zoltán Novák、Michael R. Krout、Ryan M. McFadden、Jennifer L. Roizen、John A. Enquist、David E. White、Samantha R. Levine、Krastina V. Petrova、Akihiko Iwashita、Scott C. Virgil、Brian M. Stoltz
DOI:10.1002/chem.201003383
日期:2011.12.9
functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reactionscope, and applications in target‐directed synthesis are reported. Experimental observations suggest that these alkylationreactions occur through an unusual inner‐sphere mechanism involving binding of the prochiral