Reaction of 4-t-Butyl-1, 2-benzoquinone and Methyl Linoleate

Abstract

A model reaction of hardening process of urushiol which is a principal component of Urushi (Japanese Lac) was investigated.4-t-Butyl-1, 2-bonzoquinone and methyl linoleate were mixed and allowed to stand for 48 hours at room temperature. The reaction products were characterized by GC/MS, or first separated into six fractions by thin layer chromatography and characterized by IR, NMR, UV and MS spectrometries.
The results showed the presence of methyl 9- (2-hydroxy-4- (or 5-) t-butylphenoxy) -10, 12- octadecadienoate and/or methyl 13- (2-hydroxy-4- (or 5-) t-butylphenoxy) -9, 11-octadecadienoate, methyl 9- (2, 3-dihydroxy-5-t-butylphenyl) -10, 12-octadecadienoate, methyl 13- (2, 3-dihydroxy5-t-butylphenyl) -9, 11-octadecadienoate, methyl octadecatrienoates, 4-t-butylcatechol and dimers of 4-t-butylcatechol in the reaction products.
The results suggest that hydrogen abstraction from the methylene group between two olefinic double bonds of methyl linoleate by 4-t-butyl-1, 2-benzoquinone formed the conjugated radical and t-butyl-o-semiquinone radical, and that the compounds described above were formed by combination and disproportionation between these radicals.