Options
Raubenheimer, Helgard G.
Preferred name
Raubenheimer, Helgard G.
Official Name
Raubenheimer, Helgard G.
Research Output
Now showing 1 - 1 of 1
- PublicationPyridine-derived N-heterocyclic carbenes: An experimental and theoretical evaluation of the bonding in and reactivity of selected normal and abnormal complexes of Ni(II) and Pd(II)(ACS, 2010-10-22)
; ; ; ; ; ; ; We report a thorough investigation of a series of isomeric complexes with the general formula trans-(pyridylidene)M(PPh3)2Cl (M = Pd, Ni). For the first time, a systematic comparison of normal, abnormal and remote bonding modes is presented. X-ray structural and 13C NMR data indicate the importance of carbenoid mesomeric contributions in their compound class. The catalytic performance of the palladium complexes, trans-(pyridylidene)Pd(PPh3)2Cl, as precursors in Suzuki-Miyaura-type cross-coupling suggests a correlation of remote bonding with catalyst robustness and thus effectivity. When metal precursors M(PPh3)4 are reacted with 2,4-dichloro pyridinium salts, preferential formation of remote carbene complexes occurs and indications are that electronic parameters rather than steric influences are responsible for the observed selectivity. Calculations at the BP86/TZ2P level of theory support interpretation of the results.272Scopus© Citations 68