Totally hindered phenols. 2,6-Di-t-butyl-4-(1,1-dialkyl-1-acetamide)-phenols and their persistent phenoxy radicals

2,6-Di-t-butyl-4-(1,1-dialkyl-1-acetamide)-phenols were prepared from 2,6-di-t-butylphenol, chloroform, ketone and amine with sodium hydroxide. Their phenoxy radicals were found to be more persistent than the well-known 2,4,6-tri-t-butylphenoxy blue aroxyl radical.