Electrophilic Activation of α,β‐Unsaturated Amides: Catalytic Asymmetric Vinylogous Conjugate Addition of Unsaturated γ‐Butyrolactones
作者:Ming Zhang、Naoya Kumagai、Masakatsu Shibasaki
DOI:10.1002/chem.201600740
日期:2016.4.11
Although catalytic asymmetric conjugate addition reactions have remarkably advanced over the last two decades, the application of less electrophilic α,β‐unsaturated carboxylic acid derivatives in this useful reaction manifold remains challenging. Herein, we report that α,β‐unsaturated 7‐azaindoline amides act as reactive electrophiles to participate in catalytic diastereo‐ and enantioselective vinylogous
intermediates with deconjugated butenolides and azlactones were accomplished by using a novelchiral hybrid P,S‐ligand and hydrogen bonding. By doing so, highly functionalized, optically active dihydroquinol‐2‐ones were produced with generally high reaction efficiencies and selectivities. Preliminary DFT calculations were performed to explain the high enantio‐ and diastereoselectivities.
Derivatives of 4-hydroxybutanoic acid and of its higher homologue as ligands of $g(g)-hydroxybutyrate (ghb) receptors, pharmaceutical compositions containing same and pharmaceutical uses
申请人:Bourguignon Jean-Jacques
公开号:US20050113366A1
公开(公告)日:2005-05-26
The invention concerns the field of synthesis organic chemistry applied to the pharmaceutical field and concerns novel derivatives of 4-hydroxybutanoic acid and its higher homologue, 5-hydroxypentanoic acid, their crotonic homologues, pharmaceutical compositions containing them and their pharmaceutical uses. Said novel derivatives are capable of binding with γ-hydroxybutyrate (GHB)-specific receptors and hence capable of exhibiting agonist or antagonist properties, in particular for treating sleep disorders, anxiety and general diseases of the central nervous system. The invention also concerns compounds of general formula (I) wherein the substituents are as defined in the description.
Stereoconvergent Conjugate Addition of Arylboronic Acids to α-Angelica Lactone Derivatives: Synthesis of Stereochemically Complex γ-Butyrolactones
作者:Jessica A. Griswold、Jeffrey S. Johnson
DOI:10.1021/acscatal.9b04405
日期:2019.12.6
with up to threecontiguousstereocenters. The reaction proceeds under a dynamic kineticresolution manifold by isomerizing the achiral starting material into an interconverting mixture of enantiomeric conjugate acceptors, followed by catalyst-controlled, enantiomer-selective 1,4-addition. Base-promoted racemization of the intermediate α,β-butenolide is possible due to the high kinetic and thermodynamic
A directvinylogousMichael reaction of gamma-substituted deconjugated butenolides with nitroolefins has been developed with the help of a newly identified quinine-derived bifunctional catalyst, allowing the synthesis of densely functionalized products with contiguous quaternary and tertiary stereocenters in excellent yield with perfect diastereoselectivity (>20:1 dr) and high enantioselectivity (up