Novel diketones of the structure ##SPC1## Or a tautomeric form thereof in which R.sup.1 and R.sup.2 represent hydrogen or lower hydrocarbyl groups with the proviso that the number of carbon atoms of R.sup.1 and R.sup.2 taken together is from 1-4 R.sup.3 represents a hydrogen, acyl or alkyl group containing 1-24 carbon atoms R.sup.4 represents an alcohol protecting group resistant to alkali but removable under acid reaction conditions Z represents an oxygen or sulphur atom are claimed and a process for subjecting these diketones to ring closure conditions as to form a 2,3-dihydrofuran-3-one of the following structure ##SPC2## In which R.sup.1, R.sup.2, R.sup.3 and Z indicate groups or atoms as indicated above.
A novel technique for the preparation of 4-hydroxy-5-alkyl-3-oxo-2H-furans is disclosed wherein the reaction product of an alpha-alkyl diglycolic acid diester and an oxalic acid diester is cyclized, hydrolyzed and decarboxylated. Alternatively, the corresponding 2,5-dialkyl product can be prepared by an intermediate alkylation step.
A novel technique for the preparation of 4-hydroxy-5-alkyl-3-oxo-2H-furans is disclosed wherein the reaction product of an alpha-alkyl diglycolic acid diester and an oxalic acid diester is cyclized, hydrolyzed and decarboxylated. Alternatively, the corresponding 2,5-dialkyl product can be prepared by an intermediate alkylation step.
Beta-diketones substituted by an aryl-aliphatic group in which the aliphatic chain is interrupted by a cyclic group, and useful as anti-viral agents, are prepared by interacting the appropriate aryl-aliphatic halide with an alkali metal salt of a beta-diketone.
A compound of the general formula, ##STR1## wherein R.sub.1 and R.sub.2 independently are --H, --CH.sub.3, or --CH.sub.2 CH.sub.3 ; and R.sub.3 is alkyl of from 1 to 10 carbons or aryl of from 6 to 10 carbons.
