Silver-Catalyzed Enantioselective Propargylation Reactions of N-Sulfonylketimines

Enantioselective [2 + 2] cycloaddition of N-allenamides with cyclic N-sulfonylketimines: access to polysubstituted azetidines bearing quaternary stereocenters.

A Ni(ClO4)2-catalyzed enantioselective [2 + 2] cycloaddition of N-allenamides with cyclic N-sulfonylketimines was developed, which regioselectively occurred at the proximal CC bonds of the N-allenamides. Broad substrate scope of N-allenamides and cyclic N-sulfonylketimines was observed. A range of fused polysubstituted azetidines bearing quaternary stereocenters were afforded in good yields and...

Enantioselective [2 + 2] cycloaddition of N-allenamides with cyclic N-sulfonylketimines: access to polysubstituted azetidines bearing quaternary stereocenters† †Electronic supplementary information (ESI) available: Experimental procedure, characterization data for all the new compounds, and chiral HPLC spectra for the products. CCDC 1495550. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6sc05450a Click here for additional data file. Click here for additional data file.

A Ni(ClO4)2-catalyzed enantioselective [2 + 2] cycloaddition ofN-allenamides with cyclicN-sulfonylketimines was developed, which regioselectively occurred at the proximal C]C bonds of the N-allenamides. Broad substrate scope of N-allenamides and cyclic N-sulfonylketimines was observed. A range of fused polysubstituted azetidines bearing quaternary stereocenters were afforded in good yields and ...

Ruthenium-catalyzed enantioselective propargylation of aromatic compounds with propargylic alcohols via allenylidene intermediates.

Helical chiral 2,2'-bipyridine N-monoxides as catalysts in the enantioselective propargylation of aldehydes with allenyltrichlorosilane.

A highly enantioselective synthesis of homopropargylic alcohols is achieved by using the new helical chiral 2,2'-bipyridine N-monoxide catalyst and allenyltrichlorosilane. This method can be further extended to the enantio- and regioselective propargylation of N-acylhydrazones.

Cascade synthesis of 3-quinolinecarboxylic ester via benzylation/ propargylation-cyclization.

Reactions of 2-amino-aryl alcohols with beta-ketoesters catalyzed by a catalytic amount of FeCl3 via tandem benzylation-cyclization produce the corresponding 3-quinolinecarboxylic esters in good to high yields. Extending this methodology to propargylation-cyclization, 2-nitrophenyl propargyl alcohols with beta-ketoesters catalyzed by FeCl3 and SnCl2 also produce the 4-alkyne-3-quinolinecarboxyl...