Catalysis efficiency

Catalytic hydrogenation of tnfluoroacetic acid gives tnfluoroethanol in high yield [73], but higherperfluorocarboxybc acids and their anhydndes are reduced much more slowly over rhodium, iridium, platinum, or ruthenium catalysts [7J 74] (equation 61) Homogeneous catalysis efficiently produces tnfluoroethanol from tnfluoroacetate esters [75] (equation 61)... 

Kumar K, Michalik D, Garcia Castro I, Tillack A, Zapf A, Arlt M, Heinrich T, Bottcher H, Beller M (2004) Biologically active compounds through catalysis efficient synthesis of N-(heteroarylcarbonyl)-N -(arylalkyl)piperazines. Chem Eur J 10 746-757... 

This type of alkoxylation chemistry cannot be performed with conventional alkali metal hydroxide catalysts because the hydroxide will saponify the triglyceride ester groups under typical alkoxylation reaction conditions. Similar competitive hydrolysis occurs with alternative catalysts such as triflic acid or other Brpnsted acid/base catalysis. Efficient alkoxylation in the absence of significant side reactions requires a coordination catalyst such as the DMC catalyst zinc hexacyano-cobaltate. DMC catalysts have been under development for years [147-150], but have recently begun to gain more commercial implementation. The use of the DMC catalyst in combination with castor oil as an initiator has led to at least two lines of commercial products for the flexible foam market. Lupranol Balance 50 (BASF) and Multranol R-3524 and R-3525 (Bayer) are used for flexible slabstock foams and are produced by the direct alkoxylation of castor oil. 

I. Pennequin, J. Meyer, I. Suisse, and A. Mortreux, A further application of TPPTS in catalysis Efficient sucrose-butadiene telomerization using palladium catalysts in water, J. Mol. Catal. A Chem., 120 (1997) 139-142. 

Chaudhuri, P., Hess, M., FTrke, U., and Wieghardt, K., 1998, From Structural Models of Galactose Oxidase to Homogeneous Catalysis Efficient Aerobic Oxidation of Alcohols, Angew. Chem., Int. Ed. Engl. 37 2217n2220. 

Hydroformylation is an industrially important carbonylation process that is used in the synthesis of aldehydes from olefins, CO and molecular hydrogen by homogeneous catalysis. Efficient catalyst recovery is crucial for the process to be economically viable. Pioneering work in fluorous chemistry was published in 1994 by Horvdth and Rabai, who studied the fluorous hydroformylation of olefins catalyzed by an Rh complex with a fluorous phosphine as a ligand. ... 

Z.-J. Zheng, L.-X. Liu, G. Gao, H. Dong, J.-X. Jiang, G.-Q. Lai, L.-W. Xu, RSC Adv. 2012, 2, 2895-2901. Amine-fiinctional polysUoxanes (AFPs) as efficient polymeric organocatalyst for amino catalysis efficient multicomponent Gewald reaction, a-allyhc alkylation of aldehydes, and Knoevenagel condensation. 

Deutschmaim O High temperature catalysis efficient way for chemical conversion oflogistic fuels, Chem Ing Tech 83 1954—1964, 2011a. 

As an example, catalysis efficiency in the isomerization of cyclopropane to propene can be interpreted, in part, in terms of the mass of the buffer-gas molecules. To activate CgHe, energy is most likely transferred first to a C-H bond by collision of a buffer-gas molecule with the H atom the extra... 

Fremy, G. Monflier, E. Carpentier, J.F. Castanet, Y. Mortreux, A. (1996) Expanded scope of supported aqueous-phase catalysis efficient rhodium-catalyzed hydroformylation of alpha,beta-unsaturated esters, J. Catal, 162, 339-48. 

Chiral 3-amino carbonyl compounds and 1,2-amino alcohols are among the most valuable building blocks for asymmetric synthesis and catalysis. Efficient enanti-oselective syntheses of these compounds were reported from 2000 to 2006 using enamine-based organocatalysts. For example, Mannich reactions employing aliphatic aldehyde as a donor with a-imino glyoxylate as an acceptor provide syn-adducts (74) as the major product with excellent enantiomeric excess in the presence of (S)-proline (13) as a catalyst (Table 28.5, entry 1) [41]. When the ketone is employed as a donor, the sy -isomer is obtained with excellent diastereo-and enantioselectivities (entry 2) [42]. 

---