Lewis Acid Promoted Diastereoselective Addition of TMSCN and TMSCF<sub>3</sub> to Isatin-Derived <i>N</i>-Sulfinyl Ketimines: Synthesis of Optically Active Tetrasubstituted 3-Aminooxindoles
作者:Diao Chen、Ming-Hua Xu
DOI:10.1021/jo501360g
日期:2014.8.15
A practical and efficient method for preparation of highly enantiomerically enriched 3-cyano-3-aminocaindoles and 3-trifluoromethyl-3-aminooxindoles with up to 99% optical purity by a Lewis acid promoted diastereoselective Strecker reaction and trifluoromethylation of isatin-derived N-tert-butanesulfinyl ketimines has been developed. This protocol allows direct use of N-free isatin substrates under mild conditions.
Highly enantioselective aza-Henry reaction with isatin <i>N</i>-Boc ketimines
作者:Melireth Holmquist、Gonzalo Blay、José R. Pedro
DOI:10.1039/c4cc04051a
日期:——
A highly enantioselectiveaza-Henryreaction with isatin N-Boc ketimines using a Cu(II)-BOX complex as a catalyst is described. The reaction, which does not require protection of the N1 atom, provides the corresponding nitroamines bearing a quaternary stereocentre with high yields and enantiomeric excesses (up to 99.9%).