mixture of the corresponding mono-Pummerer product 2, the bis-Pummerer product 3, and the bis-sulfide 4 in an n:1:1 ratio (n >/= 2). The 1:1 formation of 3 and 4 indicates an intermolecular interaction between sulfur atoms. The reaction with the deuterium-labeled 1-d(3)() showed that the formation of 2 occurs at the sulfenyl as well as sulfinyl groups in 1a-d(3)()-1d-d(3)(), in which the product ratio