2,4,6-Tri-ferf-butylphenol

The remarkably high isotope effects found in Reactions 10 and 10a are almost as embarrassing as was our discovery of an isotope effect of about 15 in the reaction with phenols referred to above. [For 2,6-di-tert-butyl-4-methylphenol in oxidizing styrene at 65°C. we obtained an isotope effect kH/kD = 10.6 (11). We have since carefully measured the isotope effect for 2,4,6-tri-ferf-butylphenol under the same conditions and have obtained a value 15. In these cases, hydrogen bonding to the solvent is relatively unimportant (6, 12). Similarly, DaRooge and Mahoney (9) have reported that for the reaction of 2,4,6-tri-tert-butylphenoxy radicals with 4-phenylphenol kH/kD 7.5.] Although... 

A soln. of 2 moles of 2,4,6-tri-ferf-butylphenol in benzene stirred 2 hrs. at room temp, under Og-free Ng with an aq. soln. of K-ferricyanide and KOH, the alkaline layer removed, the organic layer washed 5 times with water, a suspension of N-acetyl-L-tyrosine in ethyl acetate added with stirring which is continued until a clear greenish yellow soln. results 4-[p-(2-acetylamino-2-carboxyethyl)phenoxy]-2,4,6-tri-ferf-butyl-2,5-cyclohexadien-l-one. Y 77%. F. e. s. T. Matsuura and A. Nishinaga, J. Org. Chem. 27, 3072 (1962). 

Bromo-2,6-di-ferf-butylphenol in ether shaken 1 hr. with a soln. of K-ferri-cyanide and KOH in water under Ng -> diphenoquinone. F. e., also with 2,4,6-tri-ferf-butyl-l-phenoxyl, s. K. Ley et al., B. 97, 2670 (1958). 

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