Acetic Acid → 3,4-Diacetoxy-1-butene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 300-mL autoclave was charged with 40 mL (0.50 mol) of 3,4-epoxy-1-butene, 56.2 g (0.55 mol) acetic anhydride, 2.0 g (0.02 mol ) of triethylamine, 3.6 g (0.06 mol) acetic acid and 4.2 mL of diglyme. The autoclave was purged with nitrogen twice, then the vessel was pressurized to 8 bars (100 psig) with nitrogen. The agitator was started and an initial sample was taken. Then the mixture was heated to 125° C. During the course of 2.5 hrs, samples were obtained every 15 min for analysis by GC. GC analysis of the crude mixture after 2.5 hrs revealed a 96% yield of 3,4-diacetoxy-1-butene and 1.4% 3,4-epoxy-1-butene. The reaction was observed to be first order in 3,4-epoxy-1-butene with a first order rate constant of 0.037 min-1 (Table A). This example demonstrates the catalytic effect of a tertiary amine with three molar equivalents of acetic acid (Table B).

Herkunft & Nachweise