A direct one-pot synthesis of phenanthrene lactams, which employs a Suzuki-Miyaura coupling/aldol condensation cascade reaction of isoindolin-1-one with 2-formylphenylboronic acid, has been developed. The approach is used to efficiently produce a number of natural aristolactams, such as aristolactam BII (cepharanone B), aristolactam BIII, aristolactam FI (piperolactam A), N-methyl piperolactam A, and sauristolactam.

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Reduction O 0220Selective Reduction of Carbonyl Compounds with B-Phenoxydiisopinocampheylborane: Comparison of Its Reactivity to the Cyclohexoxy Derivative. -The title reagent shows an excellent chemoselectivity between aldehydes and other reducible functional groups such as ketones, acid chlorides, esters, nitriles, and olefins. -(CHA*, J. S.; NAM, H. T.; JANG, S. H.; KWON, S. Y.; PARK, S. J.; KWON, O. O.; Bull. Korean Chem.

Reduction O 0220Selective Reduction of Carbonyl Compounds with B-Acetoxy-and B-Trifluoroacetoxydiisopinocampheylboranes. -New Meerwein-Ponndorf-Verley-type reagents are prepared and their reducing characteristics are examined. In general, the reducing activity of Ipc2B-O-CO-CF3 appears to be stronger than that of Ipc2B-O-Ac, presumably due to the acidity increase by the electron-withdrawing fluorine-substituent. Both reagents show excellent selectivity in competitive reduction between structurally different carbonyl compounds. -(CHA*, J. S.; NAM, H. T.; PARK, S. J.; KWON, S. Y.; KWON, O. O.; Bull. Korean Chem. Soc. 27 (2006) 5, 667-671; Dep. Chem., Yeungnam Univ., Kyongsan 712-749, S. Korea; Eng.) -M. Paetzel 52-051