Organocatalytic, asymmetric synthesis of 3-sulfenylated N-Boc-protected oxindoles.

Sulfenylated oxindoles: The first asymmetric sulfenylation of N-Boc-protected oxindoles has been developed to provide products containing a tetrasubstituted stereogenic center in high to excellent yields (86-98 %) and, in most cases, excellent enantioselectivities (up to 96 % ee; see scheme).