A Frustrated Phosphane-Borane Lewis Pair and Hydrogen: A Kinetics Study.

Authors :: Özgün T
Bergander K
Liu L
Daniliuc CG
Grimme S
Kehr G
Erker G
Source :: Chemistry (Weinheim an der Bergstrasse, Germany) [Chemistry] 2016 Aug 16; Vol. 22 (34), pp. 11958-61. Date of Electronic Publication: 2016 Jul 19.
Publication Year :: 2016
Abstract: The energy profile of a frustrated Lewis pair (FLP) dihydrogen splitting system was determined by a combined experimental kinetic and DFT study. A trimethylene-bridged phosphane-borane FLP was converted into its endothermic H2 -cleavage product by sequential H(+) /H(-) addition. The system could be handled at low temperature, and the kinetics of the H2 elimination were determined to give a rate constant of kHH,exp (299 K)=(2.87±0.1)×10(-4) s(-1) in solution. The primary kinetic isotope effects were determined; for example, (kHH /kDD )exp =3.19. The system was accurately analyzed by DFT calculations.<br /> (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)