AgNO2 as the NO Source for the Synthesis of Substituted Pyrazole N-Oxides from N-Propargylamines
摘要:
A straightforward method for synthesizing the pyrazole N-oxides from N-propargylamines and AgNO2, through oxidation/cyclization reaction had been developed. AgNO2, was used as the NO source for the first time to synthesize pyrazole N-oxides. Various substituted groups on N-propargylamines proceeded smoothly, and the desired products were obtained in good yields.
Rhodium-Catalyzed Asymmetric Hydroboration/Cyclization of 1,6-Enynes Enabled by Spirosiladiphosphine Ligands: Constructing Chiral Five-Membered Rings with a Boron Handle
A rhodium-catalyzed enantioselective hydroboration/cyclization reaction of 1,6-enynes is achieved by employing a spirosiladiphosphine ligand. The process allows the synthesis of five-membered hetero- and carbocycles bearing a boron handle with high levels of activity and selectivity. Various enynes and organoboranes (HBdan, HBpin, HBmp, and HBamm) have been accommodated, and enynes containing terminal