[en] Dithioacids of phosphorus react with p-vinylbenzyltrimethylstannane forming anti-Markovnikov addition products. Reaction with S-trimethylsilyldithiophosphate proceeds with cleavage of the Sn-C bond. In the reaction of dimethoxyphosphorylsulfenyl chloride with p-vinylbenzyltrimethylstannane both reactive centers of the unsaturated compound participate. Phenylsulfenyl chloride attaches solely at the C-C double bond of the organotin partner. The difference in the course of these processes is caused by the different structures of the first intermediates. A comprehensive analysis is made of IR and NMR spectral data including the categorizing of chemical shifts and spin-spin coupling constants for all products