Intramolecular Keto Lactam Condensation: A Convenient and Straightforward Approach to Bicyclic Vinylogous Lactams
作者:Pei-Qiang Huang、Ting Fan
DOI:10.1002/ejoc.201701060
日期:2017.11.24
lyl trifluoromethanesulfonate (TBDMSOTf), lactam activation with triflicanhydride (Tf2O), and a tandem cyclocondensation reaction. The reaction can be run in a one-pot manner or in a two-step fashion, both under mild conditions. The yields for the one-pot version were 52–80 %. In some cases, the two-step version gave higher overall yields (44–85 %) than the one-pot version.
Preparation and reductive transformations of vinylogous sulfonamides (β-sulfonyl enamines), and application to the synthesis of indolizidines
作者:Joseph P. Michael、Charles B. de Koning、Tshepo J. Malefetse、Ibrahim Yillah
DOI:10.1039/b413379j
日期:——
Condensation between the methiodide salts of 1-alkylpyrrolidine-2-thiones and ethyl [(4-methylphenyl)sulfonyl]acetate or 1-[(4-methylphenyl)sulfonyl]propan-2-one afforded several 2-[[(4-methylphenyl)sulfonyl]methylene]pyrrolidines in good yield. These beta-sulfonyl enamines are sufficiently nucleophilic for cyclisation with internal electrophiles to give sulfone-substituted indolizines, potentially
作者:Alberto Brandi、Antonio Guarna、Andrea Goti、Francesco De Sarlo
DOI:10.1039/c39860000813
日期:——
Indolizine and quinolizine derivatives are obtained by rearrangement of 4,5-dihydroisoxazole-5-spirocyclopropanes with a side chain in position 3-suitable for ring-closure.