6922-60-7

We present here proton-exchanged montmorillonite-mediated an unusual transformation of 4-hydroxy and 4-methoxybenzylic alcohols to form symmetrical benzylic ethers and diarylmethanes under mild conditions. Nuclear magnetic resonance spectroscopy and density functional theory calculations support a plausible mechanism, which includes a distinctive aromatic C[sbnd]C ipso-substitution reaction with a hydroxymethyl group as the C-based leaving group.

2-(2′-hydroxyphenyl)benzotriazoles having general formula (I). The above 2-(2′-hydroxyphenyl)benzotriazoles are useful as light stabilizers for organic polymers.

2-(2′-hydroxyphenyl)benzotriazoles having general formula (I). The above 2-(2′-hydroyzphenyl)benzotriazoles having general formula (I) are useful as heat, oxygen and light stabilizers for organic polymers. In particular they are useful as UV stabilizers for organic polymers.

2-(2'-hydroxyphenyl)benzotriazoles having general formula (I): The above 2-(2'-hydroxyphenyl)benzotriazoles can be used as light stabilizers for organic polymers.

2-(2'-hydroxyphenyl)benzotriazoles having general formula (I): The above 2-(2'-hydroxyphenyl)benzotriazoles can be used as light stabilizers for organic polymers.

3,5-Di-tert-butyl-4-hydroxybenzyl acetate reacts with primary and secondary amines to give mainly the corresponding benzylamines. Base-catalyzed transformation of 3,5-di-tert-butyl-4-hydroxybenzyl acetate into 2,6-di-tert-butyl-4-methylene-2,5-cyclohexadienone occurs to a small extent. The major product of the reaction of 3,5-di-tert-butyl-4-hydroxybenzyl acetate with aqueous ammonia is bis(3,5-di-tert-butyl-4-hydroxybenzyl) ether which is formed by the action of ammonium acetate liberated during the process.

Carboxylic acid benzyl esters are formed in the reaction of carboxylic acid anhydrides with N,N-dialkyl-4(2)-hydroxy-substituted benzylamines. 4-Hydroxy-3,5-di-tert-butylbenzyl acetate exchanges an acetyl fragment for an alkoxyl fragment and benzylates phenol derivatives in the presence of an acid.

The 4-hydroxy-4-phenyl-2,6-di-t-butylcyclohexa-2,5-dienone (2) undergoes reaction in acidic conditions to give, inter alia, derivatives of an arene-1,2-diol.In poorly nucleophilic media, the 1,1'-biphenyl-4-ol (16) and the 5-phenyl-o-benzoquinone (37) are the main products.Isolation of the 4-(2-methylpropyl)cyclohexadienone derivatives (41) and (42) provides the first examples of intermolecular trapping of a four-carbon unit.The products are consistent with the intervention of the phenoxenium ion (44); the formation of the 2-methyl-1,3-benzodioxole (43) testifies to the intermediacy of such a powerful oxidant.Whereas the 4- phenyl-2-t-butyl-p-quinol (5) gave a complex mixture from which only the 1,1'-biphenyl-4-ol derivative (24) was isolated, the 2,6-di-isopropyl- and 2,6-dimethyl-analogues (4) and (6) afforded mainly the arene-1,3-diol derivatives (48) and (47), respectively.The 4-methyl-2,6-di-t-butyl-p-quinol (7) gave products arising from nucleophilic attack on an intermediate p-quinone methide; dimers were the major products in the absence of a good nucleophile.