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The near-ultraviolet (UV) photoinduced decarboxylation of o-acetylphenylacetic acid is studied with complete active space self-consistent field and density functional theory. The unimolecular decarboxylation is not in competition with the cyclization, but the cyclization reaction is prevented by the parent acid-catalyzed bimolecular decarboxylation, which is responsible for the products of C[O.sub.2] and o-acyltoluene.

Norrish type reactions for valerophenone in aqueous solution have been investigated by using the combined methods of DFT, CASSCF, and CASPT2 with molecular mechanics. It was found that formation of the intermolecular hydrogen bond in the complex of valerophenone with water results in a blue shift of the n,π* excited states, while the Coulomb interaction between valerophenone and the bulk surrounding water is mainly responsible for the red shift of the π,π* excited states. As a result, the ³ππ* state becomes the lowest triplet state and is responsible for the long triplet lifetime observed for aqueous valerophenone. The ¹nπ*, ³ππ*, and ³nπ* states were found to intersect in the same structural region, which appears to be the main reason why the intersystem crossing from ¹nπ* to ³nπ* is very efficient for aqueous valerophenone and why most aromatic ketones have unique photophysical features such as a short singlet lifetime, high phosphorescence, and weak fluorescence. The Coulomb interaction between valerophenone and the bulk surrounding water has a significant influence on the α-C-C cleavage and the 1,5-H shift reaction. The 1,5-H shift is predicted to have a very small barrier on the triplet pathway and the α-C-C bond cleavages are not in competition with the 1,5-H-shift reaction. This is in good agreement with the experimental findings that Norrish type II quantum yield is close to unity upon photoexcitation of aqueous valerophenone in the wavelength region of 290-330 nm. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed intermolecular C-N bond-forming reactions between aryl halides and amides are described using 2-dialkylphosphino-2'-alkoxyl-1,1'-binaphthyl, which is both bulky and electron-rich, as the ligand. A variety of amides, including aliphatic and aromatic primary amides, lactams, and carbamates, were viable substrates for the amidation, which exhibited good functional group compatibility. By tuning the substituents at the 2,2'-position of 1,1'-binaphthyl of the ligand, the palladium-catalyzed amidation of bulky aryl halides was realized and this coupling reaction was used to synthesize 2-amino-2'-methoxy-1,1'-binaphthyl in high yield.