926-36-3

Upstream product

• 3121-79-7 4,4-dimethyl-1-pentanol 
• 546-67-8 lead(IV) tetraacetate 
• 71-43-2 benzene 
• 558-37-2 tert-butylethylene 
• 201230-82-2 carbon monoxide 
• 590-86-3 isovaleraldehyde 
• 762-62-9 4,4-dimethylpent-1-ene 
• 50-00-0 formaldehyd 

Downstream Products

• 5375-28-0 2-neopentyl-acrylaldehyde 
• 1357292-08-0 C₂₀H₃₈N₂O₂ 
• 189152-00-9 (1R,2R)-N,N'-bis(3,3-dimethylbutyl)cyclohexane-1,2-diamine 
• 1194545-71-5 C₁₈H₃₄N₂ 
• 1472103-75-5 N-(4,4-dimethyl-pentyl)-2-ethylsulfanyl-6-methyl-4-morpholin-4-yl-benzamide 
• 1472103-77-7 N-(4,4-dimethyl-pentyl)-2-ethylsulfanyl-6-methyl-4-[(3R)-3-methyl-morpholin-4-yl]-benzamide 
• 1472103-79-9 N-(4,4-dimethyl-pentyl)-2-(ethylsulfinyl)-6-methyl-4-morpholin-4-yl-benzamide 
• 1472103-81-3 N-(4,4-dimethyl-pentyl)-2-(ethylsulfonyl)-6-methyl-4-morpholin-4-yl-benzamide 
• 1162665-53-3 C₁₆H₂₈N₂O₃ 

Relevant academic research and scientific papers

Palladium/Copper-catalyzed Oxidation of Aliphatic Terminal Alkenes to Aldehydes Assisted by p-Benzoquinone

The development of an anti-Markovnikov Wacker-type oxidation for simple aliphatic alkenes is a significant challenge. Herein, a variety of aldehydes can be selectively obtained from various unbiased aliphatic terminal alkenes using PdCl2(MeCN)2/CuCl in the presence of p-benzoquinone (BQ) under mild reaction conditions. Isomerization of the terminal alkene to the internal alkene was suppressed via slow addition of the starting material to the reaction mixture. In addition to the Pd catalyst, CuCl and BQ were essential in order to obtain the anti-Markovnikov product with high selectivity. Terminal alkenes bearing a halogen substituent afforded their corresponding aldehydes with high anti-Markovnikov selectivity. The halogen acts as a directing group in the reaction. DFT calculations indicate that a μ-chloro Pd(II)?Cu(I) bimetallic species with BQ coordinated to Cu is the catalytically active species in the case of a terminal alkene without a directing group.

Understanding a Hydroformylation Catalyst that Produces Branched Aldehydes from Alkyl Alkenes

This paper reports experimental and computational studies on the mechanism of a rhodium-catalyzed hydroformylation that is selective for branched aldehyde products from unbiased alkene substrates. This highly unusual selectivity relies on a phospholane-phosphite ligand prosaically called BOBPHOS. Kinetic studies using in situ high pressure IR (HPIR) and the reaction progress kinetic analysis methodology suggested two steps in the catalytic cycle were involved as turnover determining. Negative order in CO and positive orders in alkene and H2 were found and the effect of hydrogen and carbon monoxide partial pressures on selectivity were measured. Labeling studies found rhodium hydride addition to the alkene to be largely irreversible. Detailed spectroscopic HPIR and NMR characterization of activated rhodium-hydrido dicarbonyl species were carried out. In the absence of H2, reaction of the rhodium-hydrido dicarbonyl with allylbenzene allowed further detailed spectroscopic characterization of four- and five-coordinate rhodium-acyl species. Under single-turnover conditions, the ratios of branched to linear acyl species were preserved in the final ratios of aldehyde products. Theoretical investigations uncovered unexpected stabilizing CH-π interactions between the ligand and substrate which influenced the high branched selectivity by causing potentially low energy pathways to become unproductive. Energy span and degree of TOF control analysis strongly support experimental observations and mechanistic rationale. A three-dimensional quadrant model was built to represent the structural origins of regio- and enantioselectivity.

Crucial role of additives in iridium-catalyzed hydroformylation

Abstract This paper presents the new highly selective iridium-catalyzed hydroformylation of 1-octene with an Ir(cod)(acac)/PPh3/salt catalyst system. The addition of inorganic salts such as LiCl suppresses the hydrogenation of 1-octene and increases the yield of desired hydroformylation products. Even low amounts of LiCl (LiCl/Ir = 2/1) significantly increase the chemoselectivity of aldehydes up to 94% with a 1-octene conversion of 90% within 7 h. This catalyst is applicable to other alkenes such as 1-pentene or 1-dodecene. The high selectivities and the remarkable activity of the optimized iridium catalyst are promising in terms of successfully implementing on an industrial scale in the future.

Kinetic explanation for the temperature dependence of the regioselectivity in the hydroformylation of neohexene

The kinetics of Rh-catalyzed neohexene hydroformylation were investigated with the bulky monodentate ligand tris(2,4-di-tert-butylphenyl)phosphite. The hydrogenolysis of the Rh-acyl intermediate was identified as the rate-limiting step for both the linear and the branched aldehydes. Rate equations for both aldehydes were derived and kinetic parameters were estimated. Increased aldehyde linearity at higher temperatures, frequently observed in hydroformylation, was elucidated by deuterioformylation experiments. These showed that at 100 °C the formation of linear Rh-alkyl was more reversible than the formation of the branched derivative. The ratio of linear to branched Rh-acyl species was determined by in situ high-pressure IR spectroscopy experiments, which allowed the difference in the activation energies for the hydrogenolysis steps towards the aldehyde isomers to be quantified. The hydrogenolysis of Rh-acyl was found to be the step that caused the greatest temperature effect on the regioselectivity. Kinetics arouses curiosity: Studying the kinetics of neohexene hydroformylation catalyzed by a bulky-phosphite-modified Rh catalyst brings up the question: "What is the reason behind the temperature dependence of regioselectivity?" We answer this question by using mechanistic tools such as deuterium labeling and in situ IR spectroscopy. The hydrogenolysis step of the catalytic cycle seems to be the main step that is responsible. Copyright

An operando FTIR spectroscopic and kinetic study of carbon monoxide pressure influence on rhodium-catalyzed olefin hydroformylation

The influence of carbon monoxide concentration on the kinetics of the hydroformylation of 3,3-dimethyl-1-butene with a phosphite-modified rhodium catalyst has been studied for the pressure range p(CO)=0.20-3.83MPa. Highly resolved time-dependent concentration profiles of the organometallic intermediates were derived from IR spectroscopic data collected in situ for the entire olefin-conversion range. The dynamics of the catalyst and organic components are described by enzyme-type kinetics with competitive and uncompetitive inhibition reactions involving carbon monoxide taken into account. Saturation of the alkyl-rhodium intermediates with carbon monoxide as a cosubstrate occurs between 1.5 and 2 MPa of carbon monoxide pressure, which brings about a convergence of aldehyde regioselectivity. Hydrogenolysis of the acyl intermediate is fast at 30'°C and low pressure of p(CO)=0.2 MPa, but is of minus first order with respect to the solution concentration of carbon monoxide. Resting 18-electron hydrido and acyl complexes that correspond to early and late rate-determining states, respectively, coexist as long as the conversion of the substrate is not complete.

METHOD FOR HYDROFORMYLATION OF UNSATURATED COMPOUNDS

The invention relates to a method for hydroformylation of unsaturated compounds such as olefins and alkynes using mixtures of synthesis gas (CO/H2), in which either the unsaturated compounds and a catalyst are heated to a reaction temperature of 60 to 200° C. and the synthesis gas is then added, or the unsaturated compounds and the catalyst are brought into contact with pure CO at normal temperature in a preformation step, then are heated to reaction temperature and on reaching the reaction temperature the CO is replaced by the synthesis gas. The pressure is 1 to 200 bar and the CO:H2 ratio in the synthesis gas is in the range from 1:1 to 50:1. The iridium catalyst used comprises a phosphorus-containing ligand in the iridium:ligand ratio in the range from 1:1 to 1:100. With high catalyst activities and low catalyst use, very high turnover frequencies are achieved.

Rhodium catalyzed hydroformylation with formaldehyde and an external H 2-source

The efficiency of the syngas-free rhodium catalyzed hydroformylation of olefins with formaldehyde can be significantly improved by the addition of hydrogen gas or formic acid.

Exploring between the extremes: Conversion-dependent kinetics of phosphite-modified hydroformylation catalysis

The kinetics of the hydroformylation of 3,3-dimethyl-1-butene with a rhodium monophosphite catalyst has been studied in detail. Time-dependent concentration profiles covering the entire olefin conversion range were derived from in situ high-pressure FTIR spectroscopic data for both, pure organic components and catalytic intermediates. These profiles fit to Michaelis-Menten-type kinetics with competitive and uncompetitive side reactions involved. The characteristics found for the influence of the hydrogen concentration verify that the pre-equilibrium towards the catalyst substrate complex is not established. It has been proven experimentally that the hydrogenolysis of the intermediate acyl complex remains rate limiting even at high conversions when the rhodium hydride is the predominant resting state and the reaction is nearly of first order with respect to the olefin. Results from in situ FTIR and high-pressure (HP) NMR spectroscopy and from DFT calculations support the coordination of only one phosphite ligand in the dominating intermediates and a preferred axial position of the phosphite in the electronically saturated, trigonal bipyramidal (tbp)-structured acyl rhodium complex. Copyright

A general and efficient iridium-catalyzed hydroformylation of olefins

Breaking with conventional wisdom: Hydroformylation catalysts are generally based on rhodium; earlier, cobalt was used. Iridium, which is less expensive than rhodium, was considered too unreactive. However, iridium/phosphine complexes have now been shown to form active catalysts for the hydroformylation of olefins under mild conditions (see scheme; R1, R2=H, alkyl, aryl; R3=H, alkyl). Competing hydrogenation side reactions can be suppressed. Copyright

Isomerization of aldehydes catalyzed by rhodium(I) olefin complexes

A mixture of isomeric aldehydes is formed in a catalytic isomedzation of alkyl aldehydes with [C5Me5Rh(olefin)2] complexes. This process offers an indirect method for altering the n:iso ratio of aldehydes formed in hydroformylation reactions. For example the reaction of n-butanal with [C5Me5Rh(CH2 = CHMe)2] (1) results in the formation of a bis-alkyl carbonyl rhodium complex 2 which is the resting state during the isomerization of n-butanal to a mixture of n- and isobutanals (see scheme). In the presence of other olefins transfer formylation is observed.