Highly Enantioselective Hydrogenation of 2,4‐Diaryl‐1,5‐Benzodiazepines Catalyzed by Dendritic Phosphinooxazoline Iridium Complexes

Abstract

A PHOX with arms: A series of dendrimers with Ir phosphinooxazoline (PHOX) cores were designed and synthesized and found to be highly effective and recoverable catalysts for asymmetric hydrogenation of 2,4‐diaryl‐1,5‐benzodiazepines. An obvious positive dendritic effect on reactivity was observed, leading to chiral nitrogen‐containing heterocycles with excellent enantioselectivities.

Chiral catalysts immobilized on achiral polymers: effect of the polymer support on the performance of the catalyst

“…15). 159 Usually, the activity of the Ir-PHOX complexes is highly affected by the formation of polynuclear complexes, 160 but in the dendrimer supported systems (81) the sterically demanding dendrimer branches facilitate suitable site isolation reducing such adverse effect. In this way, the second-generation dendritic catalyst (81c) was ca.…”

Phosphination of Phenol Derivatives and Applications to Divergent Synthesis of Phosphine Ligands

“…NMR (100 MHz, CDCl3) δ 160.7, 144.5 (d, J = 19.7 Hz), 135.7 (d, J = 21.9 Hz), 133.8 (d, J = 4.4 Hz), 132.9, 132.3, 128.5, 125.7 (d, J = 7.0 Hz), 117.7 (d, J = 3.6 Hz), 117.3 (d, J = 31.5 Hz), 114.6 (d, J = 8.4 Hz), 55.3. 31 P NMR (162 MHz, CDCl3) δ -11.4.The characterization data are consistent with the literature reported data 11. …”

Catalysis Inside Dendrimers

“…63 In a 2014 account, 57 the Fan group reviewed their original work involving several series of chiral dendritic phosphorus ligands, including diphosphines, monodentate phosphoramidites, and P,N-ligands attached to the core or the focal point of Fréchet-type dendrons and their use in the asymmetric hydrogenation of prochiral olefins, ketones, and imine-type substrates using ruthenium, rhodium, or iridium complexes. [64][65][66][67][68] 3 Micellar Dendritic Catalysis: Olefin Metathesis and Click Reactions…”