title: Chelating P2-Bis-phosphazenes with a (R,R)-1,2-Diaminocyclohexane Skeleton: Two New Chiral Superbases.
abstract: The linkage of two P2-phosphazenyl groups through a C2-symmetric (R,R)-1,2-diaminocyclohexane (DACH) backbone yielded the new chiral superbases DACH-P2NMe2and DACH-P2Pyr (Pyr=pyrrolidinyl). These bases were prepared by a Kirsanov reaction and studied with respect to their spectroscopic and structural characteristics. Theoretical calculations concerning their basicity properties revealed remarkable pKBH+values of 38.1 and 39.9 on the acetonitrile scale; this makes them the strongest nonionic chiral superbases known to date.
authors.affiliation: Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032, Marburg, Germany.|Current address: FB Biologie/Chemie, Universität Bremen, Leobener Str. im NW2, 28359, Bremen, Germany.
authors.forename: Julius F
authors.initials: JF
authors.lastname: Kögel
authors.affiliation: Group for Computational Life Sciences, Rudjer Bošković Institute, Bijenička c. 54, HR-10000, Zagreb, Croatia.
authors.forename: Borislav
authors.initials: B
authors.lastname: Kovačević
authors.affiliation: Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032, Marburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Ullrich
authors.affiliation: Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032, Marburg, Germany.
authors.forename: Xiulan
authors.initials: X
authors.lastname: Xie
authors.affiliation: Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032, Marburg, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Sundermeyer
keywords: basicity; chirality; density functional calculations; phosphazenes; superbases