Experimental and Computational Studies of the Structure of Sulfonimidoyl Vinyllithiums.

tBuCH=C(Li)S(O)(NSO Tol)Ph⋅L (L=2THF, TMEDA) (1⋅L) in THF solution is a monomer with a C-Li bond according to NMR spectroscopy and cryoscopy. It was identified as CIP through the scalar C, Li coupling and Li,{ H} NOE experiments. The CIP has a six-membered C-Li-O-S-N-S chelate ring structure.