Diastereo- and enantioselective construction of chiral cyclopenta[b]indole framework via a catalytic asymmetric tandem cyclization of 2-indolymethanols with 2-naphthols†
Abstract
A catalytic asymmetric tandem cyclization of 2-indolymethanols with 2-naphthols has been established in the presence of chiral phosphoric acids, which constructed chiral cyclopenta[b]indole frameworks in generally good yields (up to 90%), high diastereoselectivities (up to >95 : 5 dr) and excellent enantioselectivities (up to 96% ee). This reaction not only provides an easy access to chiral cyclopenta[b]indole scaffolds, but also advances the chemistry of indolylmethanols, especially catalytic asymmetric transformations of indolylmethanols.