HCID 4232364, Verbindung → 4,4-Dimethyl-4-silapentane-1-sulfonic acid

A solution of sodium 3-(trimethylsilyl)-1-propanesulfonate (9 grams, 41.2 mmol) dissolved in demineralized water (75 ml) was added drop wise into a short column packed with an excess (15-20 times the molar amount of 3-(trimethylsilyl)-1-propanesulfonate) of Tulsion T-42 MP(H+) acidic ion exchange resin. Then the resin bed was washed with water until the pH of the solution eluting from the column was about 5 to 6. The water solution of the free 3-(trimethylsilyl)-1-propanesulfonic acid thus obtained was neutralized with tetra-n-butylammonium hydroxide until the pH of the solution was about 5 to 5.5. The resulting mixture was extracted with chloroform (three times) and the combined chloroform washes was washed with water (three times). The chloroform layer was separated, dried with anhydrous sodium sulfate, and concentrated under reduced pressure to remove solvent and other volatiles. The residual material was finally dried at 40° C. and 0.1 mm Hg to afford tetra-n-butylammonium 3-(trimethylsilyl)-1-propanesulfonate as a hygroscopic white solid. The yield of the product was 17.4 grams, or 97% of the theoretical amount. Proton NMR spectrum of the compound indicated that it was the desired compound.