TY  - UNPB
ID  - pittir7211
UR  - http://d-scholarship-dev.library.pitt.edu/7211/
A1  - Fu, Dezhi
TI  - I. LEWIS BASE-CATALYZED ALDOL REACTION IN THE TOTAL SYNTHESIS OF ERYTHRONOLIDE B; II. EFFORTS TOWARDS THE TOTAL SYNTHESIS OF AMPHIDINOLIDE H
Y1  - 2011/06/22/
N2  - Lewis base (trimethylsilylquinine and trimethylsilylquinidine) catalyzed acyl halide-aldehyde cyclocondensation (AAC) reactions have been developed to prepare synthetically important bispropionate units previously by the Nelson group. A new Lewis base-catalyzed diastereoselective Mukaiyama aldol reaction has extended this bispropionate unit preparation methodology to all-syn bispropionates which widely occurred in polypropionate natural products. By using phenoxides as Lewis base catalysts, enol silanes were activated and underwent a Felkin attack on an aldehyde through an antiperiplanar transition state to generate all-syn bispropionate product in high yields and excellent diastereoselectivities.All-syn bispropionate prepared from the Lewis base-catalyzed diastereoselective Mukaiyama aldol reaction has been untilized in natural product synthesis of erythronolide B establishing ˇ°syn,syn,synˇ± stereochemical relationships from C2-C5.Studies towards the total synthesis of the cytotoxic marine macrolide amphidinolide H have been disclosed. By exploiting AAC methodology, several key stereochemical relationships present in major fragments 198 and 199 were established. A highly enantioselective synthesis of methyl ketone 200 was realized from commercially available (S)-(?)-glycidol. Iodide 198 was coupled with boronic ester 199 via an efficient Suzuki reaction to form a C7-C20 fragment.
AV  - public
KW  - AAC; Amphidinolide H; Erythronolide B; Lewis Base; Macrolides; Mukaiyama Aldol; Ployketide
ER  -