Diastereoselective [3 + 2] cycloaddition of 3-ylideneoxindoles with in situ generated CF2HCHN2: syntheses of CF2H-containing spirooxindoles.

An efficient [3 + 2] cycloaddition of 3-ylideneoxindoles with in situ generated CF2HCHN2 for the syntheses of spirooxindoles has been developed. This methodology gives access to a range of relatively complex spirooxindoles featuring a CF2H group and three contiguous stereogenic centers in up to 84% yield and 99 : 1 trans/cis.

An unprecedented protocol for the synthesis of 3-hydroxy-3-phenacyloxindole derivatives with indolin-2-ones and α-substituted ketones.

An unprecedented reaction between indolin-2-ones and α-substituted ketones has been developed. Using this protocol, a wide range of biologically important 3-hydroxy-3-phenacyloxindole derivatives could be obtained in good yield (up to 93%) under mild reaction conditions. A possible mechanism of this reaction was tentatively proposed based on some control experiments and MS spectrometry analysis.