Compound 4
[(iPr3P)Ni]5(μ2-H)5(CC(Me)=CH2)
From: Cooperative carbon-atom abstraction from alkenes in the core of a pentanuclear nickel cluster
| 1H NMR | 31P{1H} NMR | HSQC | 13C{1H} DEPT-Q | ChemDraw
Compound data: CIF
Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.
To a stirring solution of [(iPr3P)Ni]5H6 (600 mg, 0.55 mmol) in 100 ml of n-pentane at 273 K, isobutylene was introduced to the 500 mL Schlenk flask until the solution was saturated with isobutylene. The solution was stirred for 0.25 h. The head-space gas was then removed under vacuum, and the dark brown solution was filtered through a plug of Celite. The solution was concentrated by vacuum evaporation, and then cooled to −40 ˚C for 40 hours, which afforded dark brown plates of 1. A second crop also afforded crystals of a combination of 1 and 3 according to 1H and 31P{1H} NMR spectra. A third crop, which was also a mix of 1 and 3, was collected and a dark brown plates of 3 were isolated which were suitable for X-Ray diffraction. 1H NMR (298 K, C6D6, 500 MHz): δ −22.05 (sextet, 2JPH=6.5 Hz, 5 H, Ni-H), δ 1.38 (dd, 3JHH= 7.3 Hz, 3JPH= 13.1 Hz, 90 H, P(CH(CH3)2)3), δ 2.28 (septet of d/apparent octet, 3JHH=7.1 Hz, 2JPH= 7.5 Hz, 15 H, P(CH(CH3)2)3), 1.62-1.78 (temperature-dependent s, 1H, isobutylene =CH2), δ 2.09 (s, 3H, isobutylene CH3), 2.91 (s, 1H, isobutylene =CH2) 31P{1H} NMR(298 K, C6D6, 202.5 MHz): δ 47.3 (s, 5P, P(CH(CH3)2)
