title: Hindered Brønsted bases as Lewis base catalysts.
abstract: KHMDS and KOtBu are well established as strong, hindered, non-nucleophilic Brønsted bases. However, in the present work these bases are applied as highly active Lewis base catalysts for the formal [2+2] cycloaddition of ketenes with aldehydes and imines.
authors.affiliation: Institute of Organic Chemistry, Clausthal University of Technology, Leibnizstr. 6, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Sobia
authors.initials: S
authors.lastname: Tabassum
authors.forename: Oksana
authors.initials: O
authors.lastname: Sereda
authors.forename: Peddiahgari Vasu Govardhana
authors.initials: PV
authors.lastname: Reddy
authors.forename: René
authors.initials: R
authors.lastname: Wilhelm