Rhodium catalysed hydroformylation of higher alkenes using amphiphilic ligands

Abstract

A variety of amphiphilic ligands has been synthesised comprising PhzArP (Ar= 3-hydroxyphenyl, 4-carboxyphenyl), Ph,Ar, _ .P ( Ar = 4-PhCH,X, X = NE& NMePh, NPh,; n = l-2) and Ph,Ar, -,P ( Ar = 3/4-pyridyl; n = l-2). In the hydroformylation of act-1-ene (80°C 20 bar syngas, toluene) the ligands were shown to be comparable with triphenylphosphine. Tumover frequencies of 2.2 X lo3 (mol aldehyde . mol Rh -' . h-' ) were found for most ligands with an act-1 -ene concentration of 0.84 M. The pyridylphosphines were up to two times faster. The selectivity of the hydroformylation is not affected by the modifications and in all cases aldehydes were formed with a n/b ratio of 2.8. Ph,P( 4-C,H&OOH) showed low catalytic activity under standard conditions. Preliminary experiments have shown that the new ligands in their protonated, water-soluble form do not produce active hydroformylation catalysts.

Linear‐selective hydroformylation of vinyl ether using Rh (acac)(2,2′‐bis{(di[1H‐indol‐1‐yl]phosphanyl)oxy}‐1,1′‐binaphthalene) – Possible way to synthesize 1,3‐propanediol

“…As shown in Table 1, for monophosphorus ligands (Entries 1-4), the excellent and good π-accepting phosphorus ligand P(N-pyrrolyl) 3 , P(OPh) 3 , achieved high conversion under this mild condition as expected. PPh 3 was a σ-donor ligand, compared with O-and N-substituted phosphorus ligands, which are π-accepting phosphorus ligand, as mentioned previously, [9] and therefore its activity was poor. In the case of P(N-indolyl) 3 , the conversion was determined to be 19% and only 9% linear aldehyde could be detected, which may be caused by significant steric hindrance of the indole substituent.…”

“…Phosphorus ligands usually play a vital role in controlling Rh-catalyzed hydroformylation. It is believed that phosphorus ligands possessing strong π-acceptors were able to make rhodium more electron deficient so that rhodium would readily coordinate to alkene, thus enhancing the reactivity [9] ; additionally, the Rh-diphosphorus ligand complex with a large bite angle could promote the formation of rhodium complexes with equatorialequatorial (ee) configuration, which is the linear aldehyde-preferred configuration, compared with its apical-equatorial (ea) isomer, in hydroformylation. [10] We applied the typical linear aldehyde-preferred diphosphorus ligand BISBI (L1) in hydroformylation as a model ligand [11] and on this basis, a pyrrolyl substituent was applied to enhance the π-acceptor properties of phosphorus atom and indolyl substituents to enhance both π-acceptor properties and steric hindrance of the ligand.…”

Diphosphine Capsules for Transition‐Metal Encapsulation

“…Bis(N,N-diethylamino)chlorophosphine, [26] (4-bromobenzyl)diethylamine, [11] and 5,11,17,23-tetrakis(sulfonato)-25,26,27,28-tetrakis(2-ethoxyethoxy)calix [4]arene tetrasodium salt 2-SO 3 Na [4b] were synthesized according to reported procedures. Solvents were dried and distilled under nitrogen prior to use.…”

“…1 4, 139.3, 134.5, 134.3, 131.1, 130.1, 129.3, 128.3, 127.7, 127.2, 124.8, 123.6, 34.5, 34.1, 31.7, 30.3 An orange suspension of D-HCl (300 mg, 269 mmol) in degassed dimethylcyanamide (48.9 mL, 6.00 mmol) was heated at 110 8C for 24 h. Subsequently, the clear brown solution was cooled to room temperature, upon which a fine brown precipitation appeared. 1 5,11,17,26,27,calix [4]arene 1 A solution of dppe-p-C 6 H 4 -CH 2 NEt 2 a (0.915 g, 1.24 mmol) in dichloromethane (15 mL) was added to a solution of [(cod)PdCl 2 ] (0.354 g, 1.24 mmol) in dichloromethane (20 mL).…”

Wasserlösliche Phosohane, XIV. Hydrophile Derivate des Triphenylphosphans mit NH2-, COOH- und P(O)(OR)2-funktionalisierten Seitenketten / Water Soluble Phosphanes, XIV. Hydrophilic Derivatives of Triphenylphosphane with NH2, COOH and P (O)(OR)2 Functionalized Side Chains

“…A [2], B [3]) sind als Katalysatorliganden für die Hydrofor mylierung und Oligomerisation von Olefinen [4] sowie die Carbonylierung von Benzylhalogeni den in Zweiphasensystemen [3] von Bedeutung. Durch Immobilisierung aromatischer Phosphane mit P (0 )(0 R )2-Resten (B) an anorganischen Ma terialien (Zirconium(IV)-phosphat, -phosphonat, -phosphit) wurden geträgerte Katalysatoren erhal ten, die für Hydroformylierungs-und Heck-Reaktionen in heterogenen Systemen mit Erfolg einge setzt wurden [5,6].…”