Alkyl dehydrogenation in iridium tri-cyclopentyl phosphines

[B(3,5‐C6H3Cl2)4]– as a Useful Anion for Organometallic Chemistry

“…With a more open coordination environment the [BAr Cl2 4 ] – anion can bind in an η 6 ‐motif to the metal centre, as we have recently reported for the [BAr F 4 ] – anion in both rhodium and iridium complexes with a chelatingphosphane–alkene ligand [M{P(C 5 H 9 ) 2 (η 2 ‐C 5 H 7 )}({η 6 ‐C 6 H 3 (CF 3 ) 2 }BAr F 3 )] (M = Rh,13a Ir13b). Here we usethe closely related Rh III complex [Rh(η 6 ‐C 6 H 5 F){κ 3 ‐P t Bu 2 CH 2 CH(CH 2 ) 2 }][BAr F 4 ]8 ( 2 [BAr F 4 ]) as a suitable starting material as this provides an open coordination site on displacement of the weakly bound fluoroarene ligand.…”

Dehydrogenation processes via C–H activation within alkylphosphines

“…This competitive process has also been observed in the case of Rh complexes. At low temperatures, it is possible to isolate complex 40 resulting from the reaction of [Rh(nbd)Cl] 2 (39) with NaBAr F 4 in the presence of 2 equivalents of PCyp 3 . However, 40 is not stable in solution and slowly transfers hydrogen from the cyclopentyl fragments to norbornadiene, thus affording 28a and 28b (Fig.…”

“…20). 39 The differences observed for C-H bond activation between cyclopentyl and cyclohexyl rings have been investigated using DFT calculations. The study made on simplified ligands (PH 2 Cyp versus PCyp 3 and PH 2 Cy versus PCy 3 ) showed thermodynamic and kinetic preferences for the first step of the dehydrogenation process.…”

A cationic gold complex cleaves BArF24

“…Cationic metal complexes with BArF 24 as a coordinating anion are known in the literature. [31][32][33][34][35][36] There, the coordination of one aromatic ring of the BArF 24 anion results in a splitting of the signals in low-temperature 1 H and 19 F NMR spectra. 31 For complex 2, however, we did not observe splitting in the 1 H NMR or 19 F NMR spectra at À78 1C.…”