A Reaction Product from Butylated Hydroxyanisole and Trimethylamine Oxide

The main reaction product obtained when butylated hydroxyanisole (BHA) and tri-methylamine oxide (TMAO) were thermally treated in liquid paraffin under a nitrogen stream at 180 C for 1 hr, was investigated. The crystalline substance obtained by the silica gel chromatography was recrystallized from ethanol and identified as the BHA dimer of biphenyltype, i.e., 2,2′-dihydroxy-5,5′-dimethoxy-3,3′-di-tert-butyl biphenyl, by means of the elementary analysis and the spectroscopic studies.

The BHA dimer was found to be inferior to BHA in the antioxidative activity which was compared according to the weight gain method, in either case when lard (at 60°C) and methyl esters of linseed oil (at 30°C) were used as substrates. The dimer showed a synergism with TMAO.