In a study of conversions of sensitive sulfinate salts to esters, a trisulfide bissulfinate, [NaO2S(CH2)4S]2S(1), was esterified with trialkyloxonium fluorborates. This procedure (Method A) was better for ethylation than use of ROH-HC1/BF3(C2H5)2O (Method B). but Method B was better for methylation. Disodium 3-sulfinopropanoate (7) was best dimethylated with CH3OH/BF3· (C2H5)2O without HCl (Method C). Method B or C gave satisfactory results with sodiump-toluenesulfinate (3), but ROH/BF3· (C2H5)2O with the free acid was better than either (Method D).p-Tolylsulfonyldiazomethane did not esterifyp-toluenesulfinic acid: only the sulfonate was isolated (10, 15–20% yield).