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A racemic cyclopentannulated pyrrolidine derivative was synthesized utilizing ruthenium oxidation and borane reduction as the key steps. Ruthenium oxidation reaction of the 1,2-dibromoalkene moiety in an N-Boc-protected tetrabromonorbornyl derivative afforded a tricyclic α-hydroxy ketone, which on alkaline hydrogen peroxide cleavage furnished a bicyclic lactam in excellent yield. Borane reduction of the N-Boc-protected bicyclic lactam gave an unexpected product as a single diastereomer resulting from the reduction of not only the lactam and ester moieties but also the ketal to the corresponding methyl ether. A plausible mechanism involving an oxocarbenium ion is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Nucleophilic racemic amines have been synthesized utilizing a C7nC5x free-radical cascade reaction from a bis-allyl amine starting material. Being potentially useful organocatalytic bases as is evident from their screening in the Baylis–Hillman reaction, optically pure amines were also synthesized from optically pure aldehydes (−) or (+)-4. Bis-allyl amides under similar radical reaction condition resulted in C7n cyclized products. [Copyright &y& Elsevier]