145439-09-4Relevant articles and documents
A New Insight into the Stereoelectronic Control of the Pd0-Catalyzed Allylic Substitution: Application for the Synthesis of Multisubstituted Pyran-2-ones via an Unusual 1,3-Transposition
Br??a, Zbyněk,Kratochvíl, Ji?í,Harvey, Jeremy N.,Rulí?ek, Lubomír,Nováková, Lucie,Ma?íková, Jana,Kune?, Ji?í,Ko?ovsky, Pavel,Pour, Milan
, p. 8053 - 8060 (2019)
Pyran-2-ones 3 undergo a novel Pd0-catalyzed 1,3-rearrangement to afford isomers 6. The reaction proceeds via an η2-Pd complex, the pyramidalization of which (confirmed by quantum chemistry calculations) offers a favorable antiperiplanar alignment of the Pd?C and allylic C?O bonds (C), thus allowing the formation of an η3-Pd intermediate. Subsequent rotation and rate-limiting recombination with the carboxylate arm then gives isomeric pyran-2-ones 6. The calculated free energies reproduce the observed kinetics semi-quantitatively.
Enantioselective Total Synthesis of Cannogenol-3-O-α- l -rhamnoside via Sequential Cu(II)-Catalyzed Michael Addition/Intramolecular Aldol Cyclization Reactions
Bhattarai, Bijay,Nagorny, Pavel
supporting information, p. 154 - 157 (2018/01/17)
A concise and scalable enantioselective total synthesis of the natural cardenolides cannogenol and cannogenol-3-O-α-l-rhamnoside has been achieved in 18 linear steps. The synthesis features a Cu(II)-catalyzed enantioselective and diastereoselective Michae