Kinugasa Reaction Research Articles

Catalytic Enantioselective Synthesis of β‐Lactams: Intramolecular Kinugasa Reactions and Interception of an Intermediate in the Reaction Cascade

Catalytic Enantioselective Synthesis of β‐Lactams: Intramolecular Kinugasa Reactions and Interception of an Intermediate in the Reaction Cascade

Catalytic enantioselective synthesis of beta-lactams: intramolecular Kinugasa reactions and interception of an intermediate in the reaction cascade.

Catalytic enantioselective synthesis of beta-lactams: intramolecular Kinugasa reactions and interception of an intermediate in the reaction cascade.

An Asymmetric Synthesis of β‐Lactams: The Use of Chiral Oxazolidones in the Kinugasa Reaction.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Cu(I)/Bis(azaferrocene)‐Catalyzed Enantioselective Synthesis of β‐Lactams via Couplings of Alkynes with Nitrones.

AbstractFor Abstract see ChemInform Abstract in Full Text.

An asymmetric synthesis of β-lactams: on the use of chiral oxazolidones in the Kinugasa reaction

Enantiopure cis and trans β-lactams 3a– 3e and 4a– 4e , respectively, have been synthesized via cycloaddition between chiral oxazolidinyl propynes 1a– 1b and nitrones 2a– 2d , in the presence of cuprous iodide ( the Kinugasa reaction).

Cu(I)/bis(azaferrocene)-catalyzed enantioselective synthesis of beta-lactams via couplings of alkynes with nitrones.

As a consequence of the wide-ranging significance of beta-lactams (e.g., use as drugs and as chiral building blocks), a great deal of effort has been dedicated to the development of methods for their stereoselective synthesis. Although considerable progress has been achieved, nearly all of the approaches that have been described are based on the use of chiral precursors; direct catalytic enantioselective routes to beta-lactams are rare as well as limited in scope. In this communication, we establish that, using a new C2-symmetric planar-chiral bis(azaferrocene) ligand, we can generate beta-lactams with very good enantiomeric excess and cis diastereoselection via catalytic enantioselective Kinugasa reactions (couplings of alkynes with nitrones). Appealing attributes of this process include the ready availability of the starting materials, the functional-group tolerance of the reaction, and the convergency of the approach.