No abstract

No abstract

The reaction of lactim ethers 1-3 with organolithium reagents has been found to be an effective method for the preparation of cyclic 2-alkyl imines 4-6. The method is most effective for the preparation of 2-aryl and sterically hindered 2-alkyl imines. In addition, treatment of 1-3 with excess organolithium provides a facile route to the rare cyclic 2,2-dialkyl amine derivatives 7-9. These reactions are characterized by mild reaction conditions and good yields and constitute a superior route to the title compounds.Our interest in cyclic 2-alkyl imines as synthons for indolizidine and quinolizidine alkaloids2 led to a search for 0-Aryloximes having various oxygenated substitution patterns have been converted to benzofurans, with implications toward natural product synthesis, through an extension of the Fischer indole type of synthesis. The effect of the substituent pattern in the benzene ring and the nature of the carbonyl derived portion of the oxime on benzofuranization were explored.

No abstract

We have shown that N-dienyl lactams are prepared in good yield by reaction of a lactam with an a,@-unsaturated aldehyde. The N-dienyl lactam is obtained with good selectivity for theEJ-isomer. The N-dienyl lactams are excellent enophiles and react with electron-deficient olefins to give exclusively the ortho regioisomer with good selectivity for the endo (2) adduct, similar to results observed for dienyl amides. In addition, the yield of the Diels-Alder adduct can be significantly enhanced by the use of aqueous solvents when compared to traditional aprotic solvents.