HERSTELLUNGSVERFAHREN VON DERIVATEN DER 3,5-DIOXOCYCLOHEXANCARBONSAEURE.

摘要

Prepn. of 3,5-dioxocyclohexanecarboxylic acid derivs. of formula (I) or salt, where R = H, alkyl, alkylthioalkyl or opt. substd. phenyl; and R' = alkyl, opt. substd. benzyl, phenethyl, phenoxy-, 2-thienyl-, alkoxy- or alkylthiomethyl; comprises: (i) cyclising a cpd. of formula (II) in presence of base to give (III), where M' = alkali metal; (ii) opt. treating (III) with acid to give (IV); (iii) reacting (III) or (IV) with R'-CO-Cl (V) to give (VI); and (v) rearranging (VI) in presence of a catalyst to give (I) and opt. converting to a salt by reacting with inorganic or organic cation.