Abstract: The invention relates to a process for the preparation of hetero)aryloxyheteroarylcarboxylic amide or ester of formula VI wherein A1, A2, A3, A4, A5 Hal, X, R1, and R4 are defined within, which process comprises preparing the heteroarylcarboxylic amide or ester of formula I or a salt thereof,  from a trichoromethyl-heteroaromatic compound of formula II and reacting the compound of formula I with an aromatic or heteroaromatic hydroxyl compound of formula VII, R4—OH  VII optionally in the presence of a base.

Abstract: The invention relates to a process for the preparation of heteroarylcarboxylic amides and esters of formula I ##STR1## in which one or two of the groups A.sup.1, A.sup.2, A.sup.3, A.sup.4, and A.sup.5 represent a nitrogen atom and the other groups each independently represent CR.sup.3,Hal represent s a halogen atom,X represents oxygen or NR.sup.2,R.sup.1 represents an optionally substituted alkyl, aryl, heteroaryl or cycloalkyl group,R.sup.2 represents a hydrogen atom or an alkyl group, orR.sup.1 and R.sup.2 together with the interjacent ring form a heterocyclic group, andR.sup.3 each independently represent a hydrogen atom or an alkyl group,which comprises heating a mixture of a compound of formula II, ##STR2## and concentrated sulfuric acid, and reacting the resulting intermediate with in alcohol or amine of formula IIIHXR.sup.1 III.

Abstract: A process for the preparation of dialkyl arylmalonates of formula I, ##STR1## comprises treating an arylmethlhalide of formula II ##STR2## with magnesium in an inert solvent, and a dialkyl carbonate or an alkyl chloroformate. A and R are as defined. The process is useful in the preparation of intermediate agro or pharmaceutical chemicals, or liquid crystals.

Abstract: An effective and efficient process for the preparation of dialkyl arylmalonates of formula I, ##STR1## (ring A and R are defined in the specification). In this process, an arylmethylhalide of formula II ##STR2## is treated with magnesium in an inert solvent, the resulting Grignard reagent is treated with a dialkyl carbonate or an alkyl chloroformiate, and the resulting reaction mixture is treated with a base.