KOH-mediated stereoselective alkylation of 3-bromooxindoles for the synthesis of 3,3′-disubstituted oxindoles with two contiguous all carbon quaternary centres

The stereoselective synthesis of 3,3 '-disubstituted oxindoles having all-carbon quaternary stereocenters has been achieved using KOH as a base with an excellent diastereomeric ratio (98 : 2). The practicability of the present methodology has been validated with the synthesis of a series of substrates in good to excellent yields. The aesthetic simplicity, accessibility, and eco-friendly base (KOH) have prompted the broader application of the present methodology in organic synthesis.

Automated summary

The stereoselective synthesis of 3,3'-disubstituted oxindoles with all-carbon quaternary stereocenters using KOH as a base has been achieved with an excellent diastereomeric ratio of 98:2. The practicality of the methodology has been demonstrated through the synthesis of a series of substrates with good to excellent yields. The aesthetic simplicity, accessibility, and eco-friendly nature of the base (KOH) have led to the broader application of this methodology in organic synthesis.