Bromine → Ethyl 2-(5-oxo-1-cyclopentenyl)acetate

Participants

Reaction Steps

In the manner described in Example 28, treatment of 1-acetoxy-2-(carbethoxymethyl)cyclopent-1-ene (Example 21) with bromine and subsequent dehydrobromination with lithium bromide-lithium carbonate in N,N-dimethylformamide gives an amber oil. This material is subjected to chromatography on diatomaceous earth using an n-heptane:methyl cellosolve system. Removal of the solvent from hold back volume 4.5-4.7 gives an oil which is then further treated with hydroxylamine hydrochloride, sodium acetate in ethanol at room temperature for 18 hours to give the desired product; b.p. 71° C. (0.12 mm); λmaxMeOH 222 mμ (10,300); λmax 5.75, 5.85, 6.15, 8.65 μ.

Provenance & Evidence