The introduction of functional groups at the 4-position of the b-sultam ring was realized by the synthesis of mono-and disubstituted derivatives by reactions of N-silylated b-sultams with electrophiles in the presence of BuLi or LDA. As electrophiles, ketones, chlorosilanes, a b-sultam, CO 2 , chloroformiate, halogen, azodicarboxylate, phenyltriazoledione, tosyl azide, 1,3,5-triazine, propyl nitrate, and phenyl isocyanate were used. Furthermore, a number of derivatives of these substitution products were synthesized. All products were characterized by standard spectroscopic methods, and conformations were studied, supported by calculation.