STRUCTURE OF THE PRODUCTS OF THE CYCLOOLIGOMERIZATION OF SULFUR-DIOXIDE WITH DIETHYL DIALLYLMALONATE

The AIBN-initiated cooligomerization of sulfur dioxide with diethyl di allylmalonate in the presence of bromotrichloromethane or thiophenol w as investigated, ES/MS and NMR studies show that 1:1 cooligomers of ci s-linked 5-membered rings are formed, Electrospray mass spectrometry d emonstrates that, in the case of CCl3Br, the end group is -CH2Br, and C-13 NMR demonstrates that the other end group is -Cl2CCl3, The thioph enol reaction leads to end groups of either -CH3 or -CH2SO2H with PhSC H2 at the other end. The molecular weight of oligomers was inversely p roportional to the concentration of the chain-transfer agent. The poly merization chain transfer constants for bromotrichloromethane and thio phenol are 4.63 x 10(-4) and 8.10 x 10(-4), respectively, at 81 degree s C.