76649-14-4Relevant articles and documents
Cerium-free Luche reduction directed by rehydrated alumina
Jones-Mensah, Ebenezer,Nickerson, Leslie A.,Deobald, Jackson L.,Knox, Hailey J.,Ertel, Alyssa B.,Magolan, Jakob
, p. 3748 - 3753 (2016/06/06)
A 1,2-regioselective reduction of α,β-unsaturated ketones to their corresponding allylic alcohols is accomplished with NaBH4 in the presence of acidic activated alumina rehydrated to the Brockmann II grade by adding 3 % w/w water. The substrate scope includes eight ketones reduced in high regio- and diastereoselectivity to their corresponding allylic alcohols. This is the first example of the strategy of systematically tuning the surface chemistry of alumina via partial rehydration in order to modulate selectivity in a reaction. Alumina is an appealing alternative to the common Luche reduction additive, CeCl3, from the perspective of cost and procedural simplicity.
Copper-catalyzed asymmetric conjugate addition to challenging michael acceptors and synthesis of relevant target molecules
Gremaud, Ludovic,Palais, Laetitia,Alexakis, Alexandre
scheme or table, p. 196 - 200 (2012/07/28)
We report herein the enantioselective Cu-catalyzed conjugate addition of organometallic reagents to sensitive Michael acceptors and their application to the synthesis of relevant target molecules. This is one of the most important methodologies to form a C-C bond in an enantioselective manner. A wide range of α,β-unsaturated aldehydes and β,γ-unsaturated-α- ketoesters has been successfully used. Reactivity, regioand enantioselectivities were strongly dependent on the reaction conditions, therefore moderate to very good results were obtained. Furthermore, γ-substituted-α-ketoesters were used as chiral building blocks for further derivatization with complete retention of the chiral information to obtain key compounds. Schweizerische Chemische Gesellschaft.
Catalytic enantioselective β-alkylation of α,β-unsaturated aldehydes by combination of transition-metal- and aminocatalysis: Total synthesis of bisabolane sesquiterpenes
Afewerki, Samson,Breistein, Palle,Pirttil?, Kristian,Deiana, Luca,Dziedzic, Pawel,Ibrahem, Ismail,C?rdova, Armando
supporting information; experimental part, p. 8784 - 8788 (2011/09/15)
Branching out! The first co-catalytic enantioselective (up to 98:2 e.r.) β-alkylation of α,β-unsaturated aldehydes by combination of simple chiral amine and copper catalysts provides β-branched aldehydes in a one-pot protocol (see scheme). The methodology was applied to the short total syntheses of bisabolane sesquiterpenes (S)-(+)-curcumene, (E)-(S)-(+)-3- dehydrocurcumene and (S)-(+)-tumerone.
