Synthesis of polysubstituted 3-aminoindenes <i>via</i> rhodium-catalysed [3+2] cascade annulations of benzimidates with alkenes
作者:Binjie Wu、Zi Yang、Hong Zhang、Lianhui Wang、Xiuling Cui
DOI:10.1039/c9cc00567f
日期:——
A novel Rh-catalysed intermolecular [3+2] cascade cyclization of benzimidates and alkenes has been developed to assemble polysubstituted 3-aminoindenes. The target products are important building blocks for organic synthesis and drug discovery. Cheap and easily available α,β-unsaturated ketones or nitroalkenes are applied as coupling partners. Acyl or nitro groups are easily introduced to 3-aminoindenes
and expeditious protocol for the synthesis of difunctionalized indenes from readily available benzimidates and nitroalkenes through rhodium‐catalyzed C−H activation and cyclization is reported here. The transformation exhibits powerful reactivity, tolerates a large number of functionalgroups, and proceeds in moderate to high yields under an ambient atmosphere, providing a straightforward method to access
β-Nitrostyrenes as electrophiles in Parham cyclization chemistry: reaction with o-lithiobenzonitrile
作者:Adam J. Clarke、David A. Hunt
DOI:10.1016/j.tetlet.2009.03.217
日期:2009.6
β-Nitrostyrenes react with o-lithiobenzonitrile, generated from the requisite aryl bromide at −100 °C by bromine–lithium exchange with n-butyllithium in THF, to afford 2-nitro-3-phenyl-3H-inden-1-ylamines resulting from 1,4-addition to the β-nitrostyrene followed by intramolecular capture of the resultant nitronate anion by the ortho-cyano functional group.