Diaryl ethanones

A -(2,3>5-Trichloro-4-oxocyclohexa-2,5-dienylidene)benzenesulfonamide oxidations of 5,6-dihydro-l,3-thiazines 24 afford excellent yields of l-(4-ethoxy-2,6-diaryl-277-l,3-thiazin-5-yl)ethanone 58 and 59 (Equation 6) <2000CHE862>. 

A further application of this approach is the s)mthesis of 1,2-diaryl-l-ethanones 12 in good to excellent yields by reaction of aryl acetic acids 11 with arenes in the presence of 85% phosphoric acid without solvent at 50°C for 30-180 min (Scheme 2.7). The reaction tolerates a variety of substituents, and groups such as methoxy and thiomethoxy are found to be highly effective. 

Veeramaneni, V. R., Pal, M., and Yeleswarapu, K. R. 2003. A high speed parallel synthesis of 1,2-diaryl-l-ethanones via a clean-chemistry C-C bond formation reaction. Tetrahedron 59 3283-3290. 

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