Potassium tert-Butoxide-Mediated Condensation Cascade Reaction: Transition Metal-Free Synthesis of Multisubstituted Aryl Indoles and Benzofurans

An efficient and facile method to synthesize valuable disubstituted 2-aryl indoles and benzofurans in good yields has been demonstrated, based on a tert-butoxide-mediated condensation reaction involving a vinyl sulfoxide intermediate. Products are obtained from N- or O-benzyl benzaldehydes using dimethyl sulfoxide as a carbon source. The methodology features a wide functional group tolerance and transition metal-free environment. Preliminary mechanistic studies suggest that the reaction involves a tandem aldol reaction/Michael addition/dehydrosulfenylation/isomerization sequence through an ionic protocol.

A formal intermolecular [4 + 2] cycloaddition reaction of 1,3-disubstituted indoles and alkylquinones

A formal [4 + 2] cycloaddition reaction of 1,3-disubstituted indoles and alkylquinones was realized to afford polycyclic indolines in good yields.

Off–on fluorometric detection of cyanide anions in an aqueous mixture by an indane-based receptor

An indanedione–coumarin conjugate behaves as an off–on type fluorescent receptor for rapid, selective, and sensitive detection of cyanide anions in an aqueous mixture via a nucleophilic interaction with the electrophilic β-carbon of the receptor.