Organocatalytic, enantioselective synthesis of benzoxaboroles via Wittig/oxa-Michael reaction Cascade of α-formyl boronic acids.

Organocatalytic, enantioselective synthesis of benzoxaboroles via Wittig/oxa-Michael reaction Cascade of α-formyl boronic acids† †Electronic supplementary information (ESI) available. CCDC 1487136. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc04522g Click here for additional data file. Click here for additional data file.

Enantioselective α-alkenylation of aldehydes with boronic acids via the synergistic combination of copper(II) and amine catalysis.

The enantioselective α-alkenylation of aldehydes has been accomplished using boronic acids via the synergistic combination of copper and chiral amine catalysis. The merger of two highly utilized and robust catalytic systems has allowed for the development of a mild and operationally trivial protocol for the direct formation of α-formyl olefins employing common building blocks for organic synthe...

Enantioselective synthesis of gabapentin analogues via organocatalytic asymmetric Michael addition of α-branched aldehydes to β-nitroacrylates.

Michael addition reaction of α-branched aldehydes to β-nitroacrylates was successfully carried out by using a mixed catalyst consisting of a primary amino acid, L-phenylalanine, and its lithium salt to give β-formyl-β'-nitroesters having a quaternary carbon centre in good yields (up to 85%) with high enantioselectivity (up to 98% ee). By using benzyl β-nitroacrylates as Michael acceptors, the o...

An organocatalytic Michael-cyclization cascade of 4-oxa-α,β-unsaturated carboxylic acids with aldehydes: facile synthesis of chiral γ-lactols and trisubstituted γ-lactones.

An organocatalytic Michael-cyclization cascade of aldehydes with 4-oxa-α,β-unsaturated carboxylic acids has been developed, giving functionalized γ-lactols with high yields and enantioselectivities. The products could be easily transformed into complex trisubstituted γ-lactones and γ-lactams.

Diastereoselective synthesis of pitavastatin calcium via bismuth-catalyzed two-component hemiacetal/oxa-Michael addition reaction.

An efficient and concise asymmetric synthesis of pitavastatin calcium (1) starting from commercially available (S)-epichlorohydrin is described. A convergent C1 + C6 route allowed for the assembly of the pitavastatin C7 side chain via a Wittig reaction between phosphonium salt 2 and the enantiomerically pure C6-formyl side chain 3. The 1,3-syn-diol acetal motif in 3 was established with excelle...