The effect of aqueous ethanol (50% v/v) on the activity of purified mushroom polyphenol oxidase has been found to be as follows: (1)The oxidation of catechol or pyrogallol is greatly stimulated,an increase in the rate of oxygen uptake of over 100% having been invariably observed with catechol as the substrate,whereas the oxidation of other substituted o-dihydric phenols is inhibited in 50% ethanol. (2)When excess ascorbic acid is added to the reaction mixture to reduce o-quinone back to catechol as soon as ...
The addition reactionof thiophenol and tert.-butylacetylene took Place slowly in the dark,giving a 1:1 adduct and smaller amounts of a 2:l adduct. The reaction could be accelerated by ight and benzoyl peroxide yielding the same Products.The reaction of thiophenol and tert.-butylacetylene in the presence of sodium ethoxide took Place very slowly,only a small amount of a 2:1 adduct was obtained. The 1:1 adduct interacted with mercuric chloride in aqueous solution yielding a carbonyl compound which...
The telomerization of methyl acetate with ethylene, using di-tert.-butyl peroxide, benzoyl peroxide, or azo-bis-iso-butyronitrile as initiator, has been studied. Experimental results show that di-tert.-butyl peroxide is much more efficient than benzoyl peroxide and azo-bis-iso-butyronitrile.