NOVELTY - Preparing 4,6-bis(aryloxy)pyrimidine compounds involves either (a1) reacting 4-phenoxy-pyrimidine compounds (II) with an alcohol or its salt or (b1) reacting pyrimidine compound with substituted phenol derivative or its salt, in the presence of 0.05-40 mol.% of tertiary-amine catalysts, and using water as reaction medium, where the reaction medium contains less than 10 wt./wt.% of organic solvent.    USE - For preparing 4,6-bis(aryloxy)pyrimidine compounds e.g. azoxystrobin (claimed) which is used as strobilurin fungicides.    ADVANTAGE - The present method utilizes water as reaction medium which is substantially free of organic solvents (i.e. less than 10 wt./wt.% compared to the reaction medium content) thus provides a more easy and convenient workup of the end-product (I), e.g. azoxystrobin, particularly water as a reaction medium is more convenient because of low cost and is much more environmentally friendly in contrast to using an organic solvent; and achieves excellent yields by addition of tertiary-amine catalysts to the reaction medium. Thus the method is more desirable than known production methods as it is more environmental friendly and reduces the production costs.    DETAILED DESCRIPTION - Preparing 4,6-bis(aryloxy)pyrimidine compounds of formula (I) involves either (a1) reacting 4-phenoxy-pyrimidine compounds of formula (II) with an alcohol of formula R6-OH or its salt or (b1) reacting pyrimidine compound of formula (III) with substituted phenol derivative of formula (IV) or its salt, in the presence of 0.05-40 mol.% of tertiary-amine catalysts, and using water as reaction medium, where the reaction medium contains less than 10 wt./wt.% of organic solvent.    LG'=a leaving group;    R1, R2, R3 and R4=G1, or T1;    G1=H, halo, cyano, nitro, alkylcarbonyl, formyl, alkoxycarbonyl, aminocarbonyl, alkylaminocarbonyl or dialkylaminocarbonyl;    T1=optionally halo-substituted alkyl, aryl, alkoxy, alkylthio, alkylsulfinyl or alkylsulfonyl;    R5=G1, T1 or a group of formulae (ia) to (ih), (ij) to (in), -CH(CH-(OCH3)2)-C(O)-OCH3, or -CH2-C(O)-OCH3;    R6=aryl, heterocyclyl or their salts (all optionally substituted);    R7=H, fluoro, chloro or bromo.    Provided that R6 and the phenyl ring substituted by R1-R5 of formula (I) are different from each other.