Hydroxy-based finishes

A major use for 2,4-di-/ f2 -amylphenol is in the production of uv stabilizers the principal one is a benzotriazole-based uv absorber, 2-(2 -hydroxy-3, 5 -di-/ f2 -amylphenyl)-5-chlorobenzotriazole [25973-55-17, which is widely used in polyolefin films, outdoor furniture, and clear coat automotive finishes (56). Another significant use for 2,4-di-/ f2 -amylphenol is in the photographic iadustry. A number of phenoxyacetic acid derivatives of... 

LA represents Lewis acid in the catalyst, and M represents Bren sled base. In Scheme 8-49, Bronsted base functionality in the hetero-bimetalic chiral catalyst I can deprotonate a ketone to produce the corresponding enolate II, while at the same time the Lewis acid functionality activates an aldehyde to give intermediate III. Intramolecular aldol reaction then proceeds in a chelation-controlled manner to give //-keto metal alkoxide IV. Proton exchange between the metal alkoxide moiety and an aromatic hydroxy proton or an a-proton of a ketone leads to the production of an optically active aldol product and the regeneration of the catalyst I, thus finishing the catalytic cycle. 

Oil-based, water-dispersible flavours (emulsions) are protected by the addition of oil-soluble antioxidants such as butylated hydroxy anisole (BHA) and butylated hydroxy toluene (BHT) to the oil phase before the emulsification process 1,000 mg/1 is the typical usage level in essential oils. Since the flavour emulsion will be used at the rate of about 0.1%, the level of antioxidant in the finished beverage will be of the order of 1 mg/1, which will safely comply with an ADI of 5 mg/kg body weight for either additive. 

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