Benzoy lation

The extracted crude luciferin was purified by Anderson s benzoy-lation method mentioned above (Anderson, 1935), followed by partition chromatography on a cellulose powder column using a mixture of ethyl acetate-ethanol-water (5 2 3 Tsuji, 1955) as the solvent, again in a hydrogen atmosphere. The luciferin obtained (3 mg) was highly pure by paper chromatography, and appeared suitable for crystallization. I... 

The dibenzoate chirality rule 155, 156 extends the application of the exciton chirality method to molecules containing no suitable chromophore, but, rather two hydroxy groups which can be converted to benzoates or cinnamates. For example, the dibenzoate 1, obtained by benzoy-lation of the ra-diol, from microbial oxidation of ethylbenzene, displays a negative exciton Cotton effect and is hence assigned the 1 S.2R configuration157. 

Wang, T. Zhang, Z. Meanwell, N. A. Benzoy-lation of dianions preparation of monoben-zoylated derivatives of symmetrical secondary diamines./. Org. Chem. 1999, 64, 7661-7662. 

Although the observed effect of the metal ions on the extent of O-benzoy-lation or C-benzoylation is important for synthetic purposes, it is questionable whether any conclusions of significance to the reactions of chelated organic ligands can be obtained from these results. It would be of great interest to repeat these reactions with the inert chelates of Rh(III), Co (III), Al(III), and Cr(III). 

Bromopentacarbonylrhenium(I) [ReBr(CO)5] promotes the Friedel-Crafts acylation of arenes with acyl chlorides. Toluene rmdergoes benzoy-lation with BC in the presence of the rhenium-based catalyst (0.1% mol), affording a mixture of ortho-, meta-, and para-methylbenzophenones in 91% yield (11 4 85 molar ratio). The yield decreases to 72% when using the same catalyst in a lower amount (0.01% mol). The process can be applied to different acyl chlorides, giving the corresponding ketones a satisfactory to high yield (Table 3.17). 

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