title: Direct synthesis of a geminal zwitterionic phosphonium/hydridoborate system--developing an alternative tool for generating frustrated Lewis pair hydrogen activation systems.
abstract: A convenient way to a new class of geminal Mes2PH(+)/B(C6F5)2H(-) pairs is presented. It utilizes triflic acid addition to trans-Mes2PCH=CHB(C6F5)2 followed by triflate/hydride exchange. Thermally induced ring-closure gave a phosphonium/boratacyclopropane zwitterion 8 which formed the Mes2PH(CHMe)B(C6F5)2H P/B FLP-H2 product 10 by subsequent treatment with triflic acid and a silane, or alternatively with dihydrogen at 90 °C. The product 10 is an active catalyst for the hydrogenation of a variety of unsaturated organic substrates, including a quinoline derivative. Treatment of compound 8 with HB(C6F5)2 gave a bifunctional borane 14 which selectively reduced carbon monoxide to the formyl stage.
authors.affiliation: Organisch-Chemisches Institut der Universität Münster Correnstraβe 40, 48149 Münster, Germany. erker@uni-muenster.de.
authors.forename: Jiangang
authors.initials: J
authors.lastname: Yu
authors.forename: Gerald
authors.initials: G
authors.lastname: Kehr
authors.forename: Constantin G
authors.initials: CG
authors.lastname: Daniliuc
authors.forename: Christoph
authors.initials: C
authors.lastname: Bannwarth
authors.forename: Stefan
authors.initials: S
authors.lastname: Grimme
authors.forename: Gerhard
authors.initials: G
authors.lastname: Erker