Organocatalytic domino annulation of in situ generated tert-butyl 2-hydroxybenzylidenecarbamates with 2-isothiocyanato-1-indanones for synthesis of bridged and fused ring heterocycles

Abstract

A one-pot efficient asymmetric domino annulation of 2-isothiocyanato-1-indanones with tert-butyl 2-hydroxybenzylidenecarbamates in situ generated from 2-hydroxyaryl-substituted α-amido sulfones was developed. This reaction firstly provided a powerful tool for the enantioselective...

Annulations involving 1-indanones to access fused- and spiro frameworks

“…In 2021, Du et al developed a one-pot asymmetric domino annulation of 2-isothiocyanato-1-indanones 72 with 2-hydroxyaryl-substituted α-amido sulfones 73 using thiourea derived tertiary amine organocatalyst 74. 52 This reaction prescribes an efficient protocol for preparing fused ring heterocycles 75 with three adjacent stereogenic centers in good yields (up to 91%) with excellent stereoselectivities (up to 99% ee and >20 : 1 dr). A plausible reaction mechanism is illustrated in Scheme 20 .…”

Bifunctional thiourea-catalyzed asymmetric [3 + 2] annulation reactions of 2-isothiocyanato-1-indanones with barbiturate-based olefins

“…However, as we know, the construction of these compounds is mostly carried out through transition-metal-catalyzed cyclization reactions [11][12][13][14], whereas strategies using bifunctional chiral thiourea catalysts are rarely reported. In 2018, Du's group reported a novel cascade reagent with the indane framework, namely, 2-isothiocyanato-1-indanone (Scheme 1a) [15], but research on its participation in the construction of chiral compounds has been relatively low [16,17].…”