61169-83-3Relevant articles and documents
Construction of Contiguous Quaternary and Tertiary Carbon Centres via the Asymmetric Michael Reaction
Tomioka, Kiyoshi,Yasuda, Kosuke,Koga, Kenji
, p. 1345 - 1346 (1987)
Michael reactions of chiral lithioenamines of α-alkyl β-oxo esters with methyl ethylidenemalonate afforded, after hydrolysis, adducts having contiguous quaternary and tertiary carbon centres, with nearly complete enantio- and diastereo-selectivity.
Iridium-catalyzed asymmetric hydrogenation of 3,3-disubstituted allylic alcohols in ethereal solvents
Bernasconi, Maurizio,Ramella, Vincenzo,Tosatti, Paolo,Pfaltz, Andreas
, p. 2440 - 2444 (2014/03/21)
Ir-phosphinomethyl-oxazoline complexes have been identified as efficient, highly enantioselective catalysts for the asymmetric hydrogenation of 3,3-disubstituted allylic alcohols and related homoallylic alcohols. In contrast to other N,P ligand complexes, which require weakly coordinating solvents, such as dichloromethane, these catalysts perform well in more ecofriendly THF or 2-MeTHF. Their synthetic potential was demonstrated with the formal total synthesis of four bisabolane sesquiterpenes. Particularly high enantioselectivity values in the asymmetric hydrogenation of 3,3-disubstituted allylic alcohols and related homoallylic alcohols have been achieved with Ir-phosphinomethyloxazoline catalysts. In contrast to other N,P-ligand complexes, which require weakly coordinating solvents, such as CH 2Cl2, these catalysts perform well in more ecofriendly THF or 2-MeTHF (see scheme; CODa =a 1,5-cyclooctadiene). Copyright
