Tetramethylammonium hydroxide → 1,1-Dimethylethyl 4-ethenylphenyl carbonate

Participants

Reaction Steps

10.00 gs (6.17×10-2 moles) of 4-acetoxystyrene was added to a 25 wt % solution of tetramethylammonium hydroxide (52 mL, 15% mole excess). After stirring for 15 minutes, a clear yellowish solution was obtained. To this solution was added with stirring to mix the phases 13.46 gs (6.17×10-2 moles) of di-tert-butyl dicarbonate. Slow formation of product was observed during 1 to 2 hours and the reaction essentially reached completion after 5 hours. A slight amount of residual 4-hydroxystyrene was detected by thin layer chromotography. The reaction mixture was extracted with two (15 mL) portion of ethyl ether. The ethyl ether extract was washed with 10 mL of 25% tetramethylammonium hydroxide(TMAH) and distilled water to remove base. The organic layer was dried over MgSO4 filtered and the solvent removed under vacuum yielding 11.87 gs (87% yield) of pure 4-tert-butyloxycarbonyloxystyrene. Analysis of the product indicated: IR(cm-1): 2950, 1755, 1275, 1150; 1H NMR(CDCl3, ppm): 1.54(s, 9H), 5.20(d(11 Hz), 1H), 5.67(d(18 Hz), 1H), 6.67(d of d(11, 18 Hz), 1H), 7.11(d(8 Hz), 2H); 7.38(d(8Hz), 2H).

Provenance & Evidence