In the presence of a catalytic amount of lithium amide, the reaction of oxophorone with electron-deficient olefins afforded bicyclo[2.2.2]octane-2,5-dione derivatives in high yields. The reaction proceeds autocatalytically by an enolate of bicyclo[2.2.2]octane-2,5-dione, generated by an initial domino Michael reaction.
Domino Michael reactions of oxophorone and its derivatives 4 with Michael partners 3 have been effected to give bicyclo[2.2.2]octane-2,5-dione derivatives 7 by a catalytic amount of a Brønsted base (NMAP-Li) generated from N-methylaminopropylated silica gel (NMAP) and n-BuLi. The NMAP pellets were efficiently reused up to six times in 86% average yield.
Twenty irone-related compounds 1–20 containing from 10 to 16 C-atoms have been identified for the first time in commercial Iris oil of Moroccan origin (Iris germanicaL.). Most of the structures and the absolute configurations of natural 6, 16, and 17 are corroborated by partial synthesis. The organoleptic properties of some of the newconstituents are discussed.