1448591-90-9Relevant academic research and scientific papers
Bulky phosphinines: From a molecular design to an application in homogeneous catalysis
Weemers, Jarno J. M.,Van Der Graaff, Willem N. P.,Pidko, Evgeny A.,Lutz, Martin,Mueller, Christian
, p. 8991 - 9004 (2013/07/25)
The design and preparation of an asymmetrically substituted and bulky phosphinine was achieved by introducing sterically demanding substituents into specific positions of a rigid phosphorus-heterocyclic framework. Compound 5 shows, at the same time, axial chirality and a sufficiently high energy barrier for internal rotation to prevent enantiomerization. Both enantiomers of 5 were isolated by means of chiral analytical HPLC, and their absolute configurations could be assigned by combining experimental data and DFT calculations. Despite its substitution pattern, 5 can still coordinate to transition-metal centers through the lone pair of electrons on the phosphorus atom. Rapid C-H activation on the adjacent aryl substituent at the 2-position of the phosphorus heterocycle was achieved by using [{CpIrCl2}2] (Cp=1,2,3,4,5- pentamethylcyclopentadienyl) as a metal precursor. A racemic mixture of 5 was applied as a π-accepting low-coordinate phosphorus ligand in the Rh-catalyzed hydroformylation of trans-2-octene, which showed a clear preference for the formation of 2-methyloctanal. Bulky phosphinines: An asymmetrically substituted, bulky, and atropisomeric phosphinine has been prepared and characterized (see figure). Rapid C-H activation on the 2-aryl substituent of the phosphorus heterocycle was achieved with [{CpIrCl2}2] (Cp=1,2,3,4,5-pentamethylcyclopentadienyl) as a metal precursor. A racemic mixture of the phosphinine acted as a π-accepting low-coordinate phosphorus ligand in the Rh-catalyzed hydroformylation of 2-octene. Copyright
