P-Cymene → 2-(Benzotriazol-2-yl)-4-methyl-6-(2-hydroxy-3-benzoyl-6-n-octyloxybenzyl)phenol

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2-(2-Hydroxy-3-diethylaminomethyl-5-methylphenyl)-2H-benzotriazole (21.0 g, 0.067 mol), 2-hydroxy-4-n-octyloxybenzophenone (22.0 g, 0.067 mol), and p-cymene (80 g) are charged to a reaction flask. The mixture is heated to dissolve, and sodium methoxide (1.0 g, 25% in methanol) is added as catalyst. The solution is heated with agitation under a nitrogen flow at reflux (176°-178° C.) for 24 hours. After cooling to room temperature, the solution is filtered, and the black filtered solid (~1 g) is discarded. The product is then precipitated with methanol. The yellow solid (12.5 g) obtained is vacuum filtered, and identified using thin layer chromatography, with toluene:acetone (1:1) as the mobile phase. To remove the yellow color, the solid product is dissolved in hot toluene, and silica gel is introduced. The silica gel is gravity filtered hot. The toluene is removed by vacuum distillation, yielding 8.2 g of the title compound as an off-white solid, m.p. 124°-126° C. H NMR shows proton resonances at 0.73 ppm, triplet, 3 protons, (terminal --CH3 in --OC8H17); 1.06-1.24 ppm, complex, 8 protons, (inner 4X-CH2 in --OC8H17); 1.32 ppm, quintet, 2 protons, (--CH2 beta to Ar--O); 1.71 ppm, quintet, 2 protons, (--CH2 gamma to Ar--O); 2.32 ppm, singlet, 3 protons (--CCH3); 4.03 ppm, triplet, 2 protons, (--CH2 alpha to Ar-0); 4.24 ppm, singlet, 2 protons, (Ar--CH2 --Ar); 6.48 ppm, doublet, 1 proton, (C8H17OCCH--); 6.82 ppm, 1 proton, (CH3CCHC--CH2 --Ar); 7.40-7.64 ppm, complex, 6 protons, (Ar--COCCHCH3 --, C8H17OCCHCH--,--NCCHC2H2 --); 7.68 ppm, doublet, 2 protons, (AR--COCCHC3H3CH), 7.95 ppm, complex, 2 protons, (--NCCHC2H2CH); 8.05 ppm, 1 proton, (CH3CCHCNCOH); 11.46 and 12.80 ppm, two singlets, two protons, (exchangeable --OH protons).

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