Thiin 1-oxides, synthesis

Oxidation of the ring system in thiins has also been achieved with hydride acceptors such as triphenylmethyl cations, and results in high yields of thiopyrylium salts. This is far more efficient than the disproportionation reactions discussed above, as the only byproduct is triphenylmethane. The reaction will be discussed in the section on synthesis. 

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