title: Reactions of an intramolecular frustrated Lewis pair with unsaturated substrates: evidence for a concerted olefin addition reaction.
abstract: The intramolecular frustrated Lewis pair (mesityl)(2)P-CH(2)-CH(2)-B(C(6)F(5))(2) was generated in situ by HB(C(6)F(5))(2) hydroboration of dimesitylvinylphosphine. The compound reacts with 1-pentyne by C-H bond cleavage. It undergoes a 1,2-addition to the carbonyl group of trans-cinnamic aldehyde to yield a zwitterionic six-membered heterocycle by B-O and P-C bond formation. The Lewis pair regioselectively adds to the electron-rich C=C double bond of ethyl vinyl ether, and it selectively undergoes an exo-cis-2,3-addition to norbornene. A combined experimental/theoretical study suggests that this reaction takes place in an asynchronous concerted fashion with the B-C bond being formed in slight preference to the P-C bond. The addition products were characterized by X-ray crystal structure analyses.
authors: Organisch-Chemisches Institut der Universität Munster, Corrensstrasse 40, 48149 Münster, Germany.
authors: Cornelia M
authors: CM
authors: Mömming
authors: Silke
authors: S
authors: Frömel
authors: Gerald
authors: G
authors: Kehr
authors: Roland
authors: R
authors: Fröhlich
authors: Stefan
authors: S
authors: Grimme
authors: Gerhard
authors: G
authors: Erker