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2-Allylphenols react with carbon monoxide and hydrogen in the presence of catalytic quantities of a cationic palladium(II) complex [(PCy 3 ) 2 Pd(H)(H 2 O)] + BF 4 -or palladium acetate and 1,4-bis(diphenylphosphino)butane, affording five-or seven-membered ring lactones (bicyclic, tricyclic, and pentacyclic) as the principal products, often in excellent yields. Use of 2-aminostyrenes as reactants and catalytic quantities of palladium acetate and tricyclohexylphosphine, affords five-membered ring lactams in high yield and selectivity. Bicyclic and tricyclic heterocycles containing six-membered ring lactams can be synthesized from the reaction of 2-allylanilines with CO/ H 2 using the catalytic system Pd(OAc) 2 /PPh 3 , while use of 1,4-bis(diphenylphosphino)butane instead of PPh 3 in the latter process results in the formation of the seven-membered lactams benzazepinones in good yield. The regiochemical control depends on the nature of the palladium catalyst, the relative pressures of the gases, and the solvent.

Novel hybrid organic–inorganic coatings were successfully prepared, coated on mild steel, and subjected to different spectral, electrochemical and morphological characterizations.