Synthesis of ‘thianthrene dimer’ by the coupling reaction of stannylthianthrenes in the presence of copper catalysts

Abstract

The coupling reaction of 1-tributylstannylthianthrene ( 5) and 2-tributylstannylthianthrene ( 7) in the presence of copper catalysts at rt afforded the thianthrene dimer 1,1′-bithianthrene ( 3), 2,2′-bithianthrene ( 8), and 1,2′-dithianthrene ( 9) in high yields. Also we obtained thianthrene oxide dimer ( R, R) ( S, S)-1-(10- S-monoxythianthrene-1-yl)thianthrene-10- S-monoxide ( 12) and ( R, S) ( S, R)-1-(10- S-monoxythianthrene-1-yl)thianthrene-10- S-monoxide ( 13) from 1-tributylstannyl-10- S-monoxythianthrene ( 10) under the same reaction condition. The final structural conformation of 3, 8, 9, and 12 was performed by X-ray crystallographic analysis. Further, the solvent effects in the coupling reactions were also examined.