Reactions of enaminones with 1-nitroolefins. Scope and limitations of a polyquinane synthesis
作者:John W. Huffman、Melanie M. Cooper、Barnabe B. Miburo、William T. Pennington
DOI:10.1016/s0040-4020(01)80490-7
日期:1992.1
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.
Descotes,G. et al., Bulletin de la Societe Chimique de France, 1970, p. 290 - 294
作者:Descotes,G. et al.
DOI:——
日期:——
Fast diastereoselective Baylis–Hillman reaction by nitroalkenes: synthesis of di- and triene derivatives
The Baylis–Hillman reaction is performed using nitroalkenes as activated alkenes, ethyl-2-bromomethylacrylate as electrophilic acceptor and DBU as catalyst base. Nitro dienes are obtained in good yields and very short reaction times. Moreover, starting from appropriate nitroalkenes it is possible to realize one pot the synthesis of trienic systems.