Neighboring effect of the lactam functionality in select reactions of 6-azaspiro[4.5]decane-1,7-dione

The susceptibility of 6-azaspiro[4.5]decane-1,7-dione (4) to nucleophilic attack was evaluated. Although steric effects preclude the 1,2-addition of many reagents, more reactive lithium and Grignard species react. Attack from the direction syn to the lactam functionality predominates. The acid-catalyzed rearrangement of select products delivered allylic alcohols carrying their double bond at varying distances from the spirocyclic carbon. These designed systems undergo hydrogenation predominantly from that pi-surface syn to the amide component, the more so when a hydroxyl is proximate to these hetero atoms. The same phenomenon operates when N-benzoylated intermediates are hydrolyzed with potassium carbonate in methanol. (c) 2005 Elsevier Ltd. All rights reserved.