[OH-].[K+].[C:3]([O:10][C:11]([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12])(OC(C)(C)C)=O.C(OC1[CH:29]=[CH:28][C:25]([CH:26]=[CH2:27])=[CH:24][CH:23]=1)(=O)C>CO.C(OCC)(=O)C>[C:14]([O:13][C:11]([O:10][C:3]1[CH:27]=[CH:26][C:25]([CH:28]=[CH2:29])=[CH:24][CH:23]=1)=[O:12])([CH3:15])([CH3:16])[CH3:17]A solution of 85 grams (1.3 moles) of potassium hydroxide in 161 grams of methanol was added in periodic additions along with 229 grams (1.0 moles) of di-t-butyl dicarbonate to a stirred solution of 101 grams (0.65 moles) of 4-acetoxystyrene in 505 grams of ethyl acetate over a period of about 40 minutes. The reagents were added concurrently in approximately equal aliquots while the reaction mixture was kept at 25° C. with an ice bath. After an additional 2 hours of reaction at 25° C., the reaction slurry was washed well with water to remove solids. The volatile components of the organic layer were stripped under vacuum to give 148 grams (83% crude yield) of 4-tertiary-butoxycarbonyloxystyrene. Vacuum distillation afforded 87 grams (65% yield) of pure product, b.p. 111° C./0.25 mm.
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