Influence of the bite natural angle of bidentate diphosphine ligands in the syngas-free branched hydroformylation of β-functionalized olefins

Microkinetic Molecular Volcano Plots for Enhanced Catalyst Selectivity and Activity Predictions

“…This chameleonic shift in the dominant product at higher temperatures is exemplified by L2 [Δ G RRS (INT4L) = −15.35 kcal/mol] which is highly active and selective for the branched product B at 353.15 K ( Figure 4 e, ([ B ]:[ L ] = 6.9:1)) while being relatively selective for the linear product L at 298.15 K ([ L ]:[ B ] = 2.8:1, Figure 4 d). Experimentally, L2 has been shown to favor B over L (albeit with a different substrate) with high temperature and long reaction times, 55 , 56 while L3 is known to favor the linear product even under harsh conditions, 57 , 58 in agreement with the results from our microkinetic volcano plots ([ L ]:[ B ] = 10.6:1). Importantly, behavior of this type cannot be easily discerned using previous generations of molecular volcano plots where the two cycles are treated independently (see Figure S1 for a comparison).…”

Valorisation of biobased olefins via Rh-catalyzed transfer hydroformylation and isomerization using formaldehyde as a CO/H2 surrogate

“…According to these results, our method outperformed those previously reported in terms of yield and regioselectivity. 16,17 In particular, the catalytic activity of [RhIJcod)Cl] 2 /PPh 3 /rac-BINAP applied to the hydroformylation of naturally occurring allylbenzenes showed a high formation of the aldehydes with yields up to 89% (2b-d and 3b-d) (Fig. 2, A).…”

“…Based on these conditions, in 2018 our group studied the Rh-catalyzed syngas-free hydroformylation of β-functionalized olefins using paraformaldehyde as the formyl source. 16 In this work, the influence of the bite angle of diphosphine ligands on the regioselectivity of the aldehyde products was investigated. The application of the optimized catalytic system resulted in the first reported transfer hydroformylation of safrole with a moderate 70% yield of the corresponding aldehydes and a poor linear : branched ( l : b ) regioselectivity of 40 : 60.…”

Microkinetic Molecular Volcano Plots for Enhanced Catalyst Selectivity and Activity Predictions

“…This chameleonic shift in the dominant product at higher temperatures is exemplified by L2 [∆G RRS (INT4L) = -15.35 kcal/mol] which is highly active and selective for the branched product B at 353.15K (Figure 4e, (B:L = 6.9:1)) while being relatively selective for the linear product L at 298.15K (L:B = 2.8:1, Figure 4d). Note that L2 has been experimentally shown to favor B over L with high temperature and long reaction times, 55,56 while L3 is known to favor the linear product even under harsh conditions, 57? in agreement with the results from our microkinetic volcano Reaction time has a similar effect to increasing reaction temperature on the product ratio that highlights the thermodynamic control of the reaction (Figure 4g). As the time of the reaction is increased, the range of descriptor values in which the branched isomer predominates increases.…”