PROCESS FOR THE PRODUCTION OF CHROMONES AND INTERMEDIATES THEREFOR

1,271,364. Process for the production of chromones and intermediates thereof. FISONS PHARMACEUTICALS Ltd. 31 July, 1969 [22 Aug., 1968], No. 40159/68. Heading C2C. A process for preparing a compound of formula comprises reacting a compound of formula with a compound of formula R2-COCOR3 in the presence of a condensing agent. In these formulµ P, Q, R and T may be the same or different and each is hydrogen or a substituent other than hydrogen; M is hydrogen, an alkali metal cation or an alkyl group; R1 is hydrogen or a substituted or unsubstituted alkyl, alkoxy or aryl group; R2 and R3 may be the same or different and one is a group reactive with a hydrogen atom in the -COCH 2 R1 group of compound (II) and the other is an -OH group or a group convertible to an -OH group (except that only one of R2 and R3 may be alkoxy and neither of R2 and R3 may be halogen); and R4 is whichever of R2 and R3 did not react with the -COCH 2 R1 group of compound (I). The compounds of Formula I wherein R4 is a group convertible to an -OH group obtained by the process of invention may be cyclized to chromone compounds of the formula The invention also comprises a compound of Formula I wherein R4 is other than an alkoxy group.