Enantioselective construction of spirodihydrofuran oxindoles via one-pot organo-/iodine sequential catalysis

Abstract

A high efficient strategy was first developed for the enantioselective construction of spirodihydrofuran oxindoles via the one-pot Michael/iodization/SN2 nucleophilic substitution sequence. The reaction features easy operation, base and transition-metal free,...

Metal-Free Regioselective Oxa-Michael Approach to Access Spirooxindole-Fused Tetrahydrofuran/Tetrahydropyran through [3 + 2]/ [4 + 2] Spirocyclization of Methyleneindolinones with Haloalcohols

“…Methyleneindolinones have emerged as a useful synthon for preparing spirocyclic compounds and significant achievements have been made with various nucleophiles . Michael addition reactions are highly efficient to construct spirooxindole-fused derivatives, through nucleophilic addition on electrophilic methyleneindolinones at C3′ or C3 position. , Organocatalytic asymmetric oxa-Michael reaction provides an alternative powerful strategy for the synthesis of complex molecules with contiguous multiple stereocenters . Along with this the regioselective [3 + 2] and [4 + 2] reactions of methyleneindolinones allow for the facile construction of spirocyclic oxindoles with one or two contiguous quaternary centers …”