Synthesis of Pyrrolyl-, Indolyl-, and Carbazolylphosphanes and Their Catalytic Application as Ligands in the Hydroformylation of 2-Pentene

Abstract

The synthesis of π-acceptor ligands of the type PAr x R 3−x (x = 0−2; R = pyrrolyl, indolyl, carbazolyl; Ar = aryl) (1−8, 10, 12, 13) and P(pyrrolyl) 2 (carbazolyl) (11) is described. These ligands can be prepared in good to excellent yields by treatment of the corresponding free heterocyclic amines with phosphorus chlorides in the presence of base. The utilization of pyrrolyl-, indolyl-, and carbazolylphosphanes in the rhod-

Strong π-Acceptor Ligands in Rhodium-Catalyzed Hydroformylation of Ethene and 1-Octene: Operando Catalysis

“…The carbazole substituent of L4 decreased the activity of the catalytic system. This effect was previously observed by Beller in 2-pentene hydroformylation . Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1 , which is in agreement with their similar steric and electronic properties.…”

“…This effect was previously observed by Beller in 2-pentene hydroformylation. 24 Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1, which is in agreement with their similar steric and electronic properties. Interestingly, the more bulky ligand L6 leads to very high activity, showing the beneficial effect of steric hindrance in this case.…”

Strong π-Acceptor Ligands in Rhodium-Catalyzed Hydroformylation of Ethene and 1-Octene: Operando Catalysis

“…The carbazole substituent of L4 decreased the activity of the catalytic system. This effect was previously observed by Beller in 2-pentene hydroformylation . Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1 , which is in agreement with their similar steric and electronic properties.…”

“…This effect was previously observed by Beller in 2-pentene hydroformylation. 24 Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1, which is in agreement with their similar steric and electronic properties. Interestingly, the more bulky ligand L6 leads to very high activity, showing the beneficial effect of steric hindrance in this case.…”

Rhodium-Catalyzed Hydroformylation and Deuterioformylation with Pyrrolyl-Based Phosphorus Amidite Ligands: Influence of Electronic Ligand Properties

“…The rate of hydroformylation remained very low. Thus, the selectivities are comparable with those of Jackstell et al,5g using monodentate pyrrolyl phosphorus ligands, but the rates are lower.…”

“…The results of the hydroformylation reaction of 1-octene for systems based on 1 and 2 are presented in Table . The activity and selectivity obtained with ligand 1 are in the range of those observed with bulky phosphite ligands . At the rhodium concentration used, the ligand-to-rhodium ratio of 5 is the minimum amount of ligand needed; the use of lower L/Rh ratios resulted in a large amount of 2-octene and we observed that the catalyst activity increased during the reaction.…”

Sterically hindered electron-withdrawing ligands: the reactions of N-carbazolyl phosphines with rhodium and palladium centres

“…The 31 P{ 1 H} NMR spectra showed single resonances at d 32.7 for L 1 , d 52.9 for L 2 and d 77.6 for L 3 , the values for L 1 and L 3 in agreement with those previously reported. 18 The observed progressive increase in chemical shift with increase in the number of carbazolyl rings is in agreement with the reduced r-basicity a dichloromethane solution. The molecular structure of trans-[RhCl(CO)(L 2 ) 2 ] is shown in Fig.…”

Strong π-Acceptor Ligands in Rhodium-Catalyzed Hydroformylation of Ethene and 1-Octene: Operando Catalysis

“…The carbazole substituent of L4 decreased the activity of the catalytic system. This effect was previously observed by Beller in 2-pentene hydroformylation . Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1 , which is in agreement with their similar steric and electronic properties.…”

“…This effect was previously observed by Beller in 2-pentene hydroformylation. 24 Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1, which is in agreement with their similar steric and electronic properties. Interestingly, the more bulky ligand L6 leads to very high activity, showing the beneficial effect of steric hindrance in this case.…”

Rhodium-Catalyzed Hydroformylation and Deuterioformylation with Pyrrolyl-Based Phosphorus Amidite Ligands: Influence of Electronic Ligand Properties

“…The rate of hydroformylation remained very low. Thus, the selectivities are comparable with those of Jackstell et al,5g using monodentate pyrrolyl phosphorus ligands, but the rates are lower.…”

“…The results of the hydroformylation reaction of 1-octene for systems based on 1 and 2 are presented in Table . The activity and selectivity obtained with ligand 1 are in the range of those observed with bulky phosphite ligands . At the rhodium concentration used, the ligand-to-rhodium ratio of 5 is the minimum amount of ligand needed; the use of lower L/Rh ratios resulted in a large amount of 2-octene and we observed that the catalyst activity increased during the reaction.…”

Sterically hindered electron-withdrawing ligands: the reactions of N-carbazolyl phosphines with rhodium and palladium centres

“…The 31 P{ 1 H} NMR spectra showed single resonances at d 32.7 for L 1 , d 52.9 for L 2 and d 77.6 for L 3 , the values for L 1 and L 3 in agreement with those previously reported. 18 The observed progressive increase in chemical shift with increase in the number of carbazolyl rings is in agreement with the reduced r-basicity a dichloromethane solution. The molecular structure of trans-[RhCl(CO)(L 2 ) 2 ] is shown in Fig.…”

Strong π-Acceptor Ligands in Rhodium-Catalyzed Hydroformylation of Ethene and 1-Octene: Operando Catalysis

“…The carbazole substituent of L4 decreased the activity of the catalytic system. This effect was previously observed by Beller in 2-pentene hydroformylation . Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1 , which is in agreement with their similar steric and electronic properties.…”

“…This effect was previously observed by Beller in 2-pentene hydroformylation. 24 Binaphthol-substituted ligand L5 shows an activity very comparable to that of L1, which is in agreement with their similar steric and electronic properties. Interestingly, the more bulky ligand L6 leads to very high activity, showing the beneficial effect of steric hindrance in this case.…”

Rhodium-Catalyzed Hydroformylation and Deuterioformylation with Pyrrolyl-Based Phosphorus Amidite Ligands: Influence of Electronic Ligand Properties

“…The rate of hydroformylation remained very low. Thus, the selectivities are comparable with those of Jackstell et al,5g using monodentate pyrrolyl phosphorus ligands, but the rates are lower.…”

“…The results of the hydroformylation reaction of 1-octene for systems based on 1 and 2 are presented in Table . The activity and selectivity obtained with ligand 1 are in the range of those observed with bulky phosphite ligands . At the rhodium concentration used, the ligand-to-rhodium ratio of 5 is the minimum amount of ligand needed; the use of lower L/Rh ratios resulted in a large amount of 2-octene and we observed that the catalyst activity increased during the reaction.…”

Sterically hindered electron-withdrawing ligands: the reactions of N-carbazolyl phosphines with rhodium and palladium centres

“…The 31 P{ 1 H} NMR spectra showed single resonances at d 32.7 for L 1 , d 52.9 for L 2 and d 77.6 for L 3 , the values for L 1 and L 3 in agreement with those previously reported. 18 The observed progressive increase in chemical shift with increase in the number of carbazolyl rings is in agreement with the reduced r-basicity a dichloromethane solution. The molecular structure of trans-[RhCl(CO)(L 2 ) 2 ] is shown in Fig.…”