The reaction of several 2-aminocyclohex-2-en-1-ones with cyclic nitroolefins has been explored as a possible synthetic approach to polyquinanes. 2-Pyrrolidino, 2-piperidino and 2-morpholinocyclohex-2-en-1-one react with 1-nitrocyclopentene to provide substituted triquinanes. Reactions involving 5,5-dimethyl-2-morpholinocyclohex-2-en-1-one were unsuccessful as were those using 4,4-dimethyl-1-nitrocyclopentene. 5-Methyl-2-morpholinocyclohex-2-en-1-one and 1-nitrocyclopentene provide the corresponding triquinane, plus a by-product in which the amino substituent has been lost. The reactions of other selected nitroolefins have been carried out, and the products are described. The results of these reactions are rationalized in terms of an inverse electron demand Diels-Alder reaction to afford an intermediate oxazine N-oxide, which then undergoes further transformations to afford the observed products.
reaction between ylide Ph3PCCO, amines and aldehydes is known to afford selectively (E)-α,β-unsaturated amides. We applied a variant of this methodology to the preparation of (2E,4Z)-dienamides 11 utilizing the phosphonium salt formation from ethyl 5-aminopentanoate hydrochloride and Ph3PCCO followed by deprotonation with DBU and a Wittigolefination of the corresponding ylide with various (Z)-α,β-unsaturated
[EN] AZACYCLIC COMPOUND, AND PREPARATION METHOD THEREFOR AND USE THEREOF<br/>[FR] COMPOSÉ AZACYCLIQUE, SON PROCÉDÉ DE PRÉPARATION ET SON UTILISATION<br/>[ZH] 氮杂并环化合物、其制备方法及其用途