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In the presence of norbornene, Pd(OAc) 2 smoothly catalyzed the meta -C-H activation process of N-phenylbenzamide ( 4 ) and yielded a norbornene fused product, (1 R ,4 S ,4a R ,8b S )-N-phenyl-1,2,3,4,4a,8b-hexahydro-1,4-methanobiphenylene-5-carboxamide ( 5a ). The employment of Ag(OAc) is crucial to the success of this reaction. Norbornene related compounds, dicyclopentadiene and norbordiene, were used as the reagents and structurally similar compounds, 5b and 5c were formed although with much lower yields. Similar reaction was carried out for using N-benzylbenzamide ( 9 ) as starting reagent. The resulted norbornene fused product (1R,4S,4aR,8bS)-N-benzyl-1,2,3,4,4a,8b-hexahydro-1,4-methanobiphenylene-5-carboxamide ( 10 ) shows that the C-H activation indeed took place at the phenyl ring of acetophenone part rather than the benzyl side. Crystal structures of 5a , 5c and 10 were determined by X-ray diffraction methods. A reaction mechanism is proposed to account for the formation of 5a , which could be extended to describe the generation of other structurally related compounds as well. [ABSTRACT FROM AUTHOR]

Several secondary phosphine oxides (SPOs, 2a-2d ) as well as 2a -chelated palladium complex 2a_Pd were employed in Catellani type reaction for the synthesis of 1-methyl-9 H -carbazole ( 4 ) from 2-iodotoluene and N -(2-bromophenyl)acetamide ( 3 ). The application of these ligands ( 2a-2d ) and palladium complex ( 2a_Pd ) in this reaction is beneficial in terms of increasing the yield of the major product, 4 . An elaborated mechanism was proposed to account for the observation of 4 as well as some side products, 5 , 6 , 7 , and 8 , via C-C and C-N bonds formation processes. [ABSTRACT FROM AUTHOR]