Lithiation of the Tin-containing Sulfone Me_3SnCH_2CH_2CH_2SO_2C_6H_4CH_3-4

摘要

The tin-containing sulfide Me_3Sn(CH_2)_3-S-C_6H_5CH_3-4 obtained by photoaddition of 4-toluene-thiol to allyltrimethyltin was oxidized with hydrogen peroxide to synthesize the tin-containing sulfone Me_3Sn(CH_2)_3-SO_2-C_6H_4CH_3-4, the tin and sulfur atoms in which are separated by a trimethylene bridge. Treatment of the sulfone with butyllithium gave a first tin-containing lithium salt having a red-brown color. The exchange reaction of this salt with methyl iodide resulted in formation of two new isomeric tin-containing sulfones Me_3SnCH_2CH_2CH(CH_3)-SO_2-C_6H_4CH_3 and Me_3Sn(CH_2)_3-SO_2-C_6H_4CH_2CH_3 identified by ~1H NMR spectroscopy. The latter result implies that the tin-containing sulfone is lithiated both by the methylene group adjacent to the sulfonyl group and by the toluene methyl group.