Convenient syntheses of alkyl β-resorcylate derivatives

Abstract
Syntheses of methyl 2,4-dihydroxy-6-methyl-(1a) and -3,6-dimethylbenzoates (1b) and methyl 2,4-dihydroxy-6-pentylbenzoate (1c) are described. Condensation reactions of dimethyl sodiomalonate with the dianion derived from pentane-2,4-dione or the dimerisation of the methyl acetoacetate dianion or the acetylation of the trianion derived from methyl 3,5,7-trioxo-octanoate gave (1a)(⩽78%) after work-up at pH 9. Analogous convenient, short, optimised syntheses of (1b and c) are given in detail.