The interaction of 1,3-bis(dibromomethyl)benzene with two types of aprotic nonionic nucleophiles was studied: trimethyl orthoformate and trimethyl phosphate. In the case of the orthoester in the presence of 10 mol% anhydrous zinc chloride as a catalyst at 80°C the reaction is complete within 1 hour. Tetramethyl diacetal of isophthalaldehyde is formed - 1,3-bis(dimethoxymethyl)benzene. To prevent aldehyde formation, an excess of orthoester is used. The corresponding di-α-chloroester, 1,3-bis[(methoxy)chloromethyl]benzene, is synthesized by treating the diacetal with SOCl2 or P(III) chloride. The latter, when heated, is dechloromethylated and converted into isophthalaldehyde, and when treated with trimethyl phosphite, diphosphonate is formed. The reaction of 1,3-bis(dibromomethyl)benzene with trimethyl phosphate in the presence of ZnCl2 as a catalyst was studied for the first time. A previously undescribed diheterofunctional compound, 3-(dibromomethyl)benzenecarbaldehyde - a new promising synthon for organic synthesis, has been synthesized. A method for its combined production with the corresponding dialdehyde has been developed. The composition and structure of the synthesized compounds were confirmed by elemental analysis and 1H, 13C, 31P NMR spectra. A mechanism for the catalytic transformation of the dibromomethyl group into an aldehyde group has been proposed. When zinc chloride interacts with one of the bromine atoms of the dibromomethyl group, a donor-acceptor complex (DAC) is formed, which is transformed into a bipolar ion. The phosphoryl oxygen atom attacks the positively charged methine carbon atom of the dipolar ion. The resulting quasiphosphonium salt is converted according to the second stage of the Michaelis-Arbuzov reaction into a debromodimethoxyphosphoryloxylation product. The latter, being unstable under the reaction conditions (130°C), decomposes into aldehyde and bromophosphate. Research data conducted at the Kazan State Medical Academy show that tetramethyl diacetal of isobutyric aldehyde exhibits bactericidal activity.