Highly Reactive Cyclic Monoaryl Iodoniums Tuned as Carbene Generators Couple with Nucleophiles under Metal-Free Conditions.

Cross-coupling reactions between aryl iodide and nucleophiles have been well developed. Iodoniums equipped with a reactive C-I(III) bond accelerate cross-coupling reactions of aryl iodide. Among them, cyclic diaryliodoniums are more atom economical; however; they are often in the trap of metal reliance and encounter regioselectivity issues.

Domino Carbopalladation/C-H Activation as a Quick Access to Polycyclic Frameworks.

A new type of domino reaction for synthesis of heterocycles fusing the important bioactive cores, such as oxindole, indoline, and isoquinoline, is presented. Upon exposure to the very common palladium catalyst, the conceptually designed N-alkenyl iodobiaryls undergo a sequential carbopalladation/C-H activation to build polycyclic frameworks. These novel unique frameworks may provide structure sources in fragment-based drug discovery.

Enantioselective synthesis of polyhydroxyindolizidinone and quinolizidinone derivatives from a common precursor.

A concise asymmetric synthetic route to two new tetrahydroxyindolizidinone and quinolizidinone derivatives has been developed from a common intermediate which featured a highly selective dihydroxylation reaction and a RCM reaction as key steps.

δ,ε-Unsaturated α,β-diamino acids as building blocks for the asymmetric synthesis of diverse α,β-diamino acids.

A building block approach for the synthesis of α,β-diamino acids is described, which involves the diastereodivergent preparation of two sets of orthogonally protected δ,ε-unsaturated α,β-diamino acids as templates for the preparation of 12 new α,β-diamino acids of biological relevance using simple techniques.

Enantiodivergency and enantioconvergency in the synthesis of the dendrobate alkaloid 241D.

A diastereodivergent preparation of two N-alkenylnitrones (9 and 11) from easily available (R)-2,3-O-cyclohexylideneglyceraldehyde (5) led to an enantiodivergent synthesis of both enantiomers of the dendrobate alkaloid 241D in a sequential two-directional approach involving intramolecular nitrone cycloaddition as the key step. Either of these two nitrones could, in principle, be utilized for the preparation of the title compounds in an enantioconvergent fashion as well. The methodology was extended to prepare an analogue (33) of (-)-241D.

Enantiodivergent synthetic entry to the quinolizidine alkaloid lasubine II.

Intramolecular cycloaddition of the syn- and the anti-nitrone 9 and 13 leads stereoselectively to the azabicyclic compounds 10 and 14 which may provide access to both enantiomers of the quinolizidine alkaloid lasubine II.