Adams immobilized

Heitkamp MA, V Camel, TJ Reuter, WJ Adams (1990) Biodegradation ofp-nitrophenol in an aqueous waste stream by immobilized bacteria. Appl Environ Microbiol 56 2967-2973. 

Tanaka Y, Adams DH, Hubscher S, Hirano H, Siebenlist U, Shaw S. T-cell adhesion induced by proteoglycan-immobilized cytokine MIP-1 beta. Nature 1993 361 79-82. 

The selectivity in favor of the desired monobenzylated product was found to be >99% and the immobilized Pt02 was found to be 4-5 times more active than the commercial Adams catalysts. In solution or in immobilized form, the PtOz colloid is effective in the hydrogenation of carbonyl compounds or of olefins. Recently, the heterogeneous catalytic amination of aryl bromides by immobilized Pd(0) particles has been reported [163], Secondary amines such as piperidine and diethyl amine are used in the amination of aryl bromides and the reaction proceeds with good turnover numbers and regio-control. The catalysts can be reused repeatedly without loss of activity or selectivity after filtration from the reaction mixture. 

One of the first cross-coupling reactions performed on solid supports was the Stille reaction [250] which is a paUadium-catalyzed reaction of a trialkylaryl or trialkylalkenyl stannane with an aromatic iodide, bromide or triflate. In contrast to the process in liquid-phase, the organotin reagent is easily removed from the solid-phase because of the subsequent washing processes. Immobilized aryl halides have been frequently coupled with aryl and alkenylstannanes, whereas stan-nanes attached to the solid support have been used less frequently for the StiUe reaction. An example is the synthesis of a benzodiazepine library by EUman et al. Recently, a Stille cross-couphng reaction has been employed in the synthesis of al-kenyldiarylmethanes (ADAM) series of non-nucleoside HlV-1 Reverse Transcriptase Inhibitors (Scheme 3.14) [251]. 

Rosevear, A., Kennedy, J.F. and Cabral, J.M.S. (1987) Immobilized enzymes and cells. Bristol Adam Hilger. 

The practical difficulty with carrying out a crystalhzation DTR process is the need to operate under conditions that allow selective crystalhzation of the least soluble diastereomer while permitting the racemization to take place. Amine racemization catalysts, such as SCRAM , Shvo, Pd/C, and Adam s, are more active at higher temperatures, which runs counter to the conditions required for crystaUization. A solution to this problem is to separate the diastereomeric resolution and racemization steps but couple them with a flow engineering design. In this way each reaction can be operated under optimal conditions for example, temperature, concentration and solvent, via an intermediary solvent exchange unit Since the racemization catalyst itself may affect the crystalhzation (or indeed the crystalhzation may affect the catalyst), it is preferred to keep them separate. This can be achieved by having the catalyst or product either permanently or temporarily in a different phase by immobilization, extraction, precipitation, distil-... 

The vadose zone beneath the cultivated soil horizon is the last barrier that can effectively detoxify, adsorb, or immobilize leaching herbicides before they reach aquifers. In most cases, a decrease in degradation rates is observed with increasing depth (Harper et al., 1990 Adams and Thurman, 1991 Fomsgaard, 1995 Kruger et al., 1997 Miller et al, 1997 Vanderheyden et al., 1997). 

Tanaka, Y., Adams, D.H., Hubscher, S., Hirano, H., Siebenlist, S. and Shaw, S. (1993). Adhesion induced by proteoglycan-immobilized cytokine MIP-l/S. Nature 361, 79-82. 

Insects are usually held in groups of ten. Adams showed that cross-contamination occurs between individuals. A female cockroach could transfer a dose sufficient to kill a male. A case could be made for holding insects separately unless the material has such a slow action that return of the insects to their harbourage would occur in the field before immobilization. 

Reaction of solutes with mineral surface sites is analogous to the immobilized tcaclant model discussed by Adam and Delbruck (1968). A difference is that many sites line the surface, and lateral movement may bring the adsorbed solute lu contact with sites exhibiting higher reaction free energies. 

Sasso S V, Pierce R J, Walla R and Yacynych A M 1990 Electropolymerized 1,2-diaminobenzene as a means to prevent interferences and fouling and to stabilize immobilized enzyme in electrochemical biosensors A aA Chem. 62 1111-7 Gerhardt G A, Oke A F, Nagy G, Moghaddam B and Adams R N 1984 Naflon-coated electrodes with high selectivity for CNS electrochemistry Brain Res. 290 390-5... 

The aqueous colloidal Adams catalyst can be immobilized conveniently on solid carriers such as AI2O3 by adding the calculated amount of solid material to the aqueous colloidal solution and stirring. However, prior reduction to the zerovalent form followed by immobilization is actually more efficient [54]. After washing with methanol several times to remove the surfactant, the heterogeneous catalysts were examined by TEM which showed that essentially no undesired agglomeration had occurred (1.9nm particles). 

Adam, T., Unger, K. K., Dittmann, M. M., and Rozing, G R, Towards the eolumn bed stabihzation of columns in capillary electroendosmotic chromatography immobilization of microparticulate sflica columns to a continuous bed. Journal of Chromatography A, 887, 327-337, 2000. 

Rosevear, A. et al., Immobilized Enzymes and Cells, Adam Hilger, Philadelphia, PA, 1987. 

Lindner E., Jaeger A., Auer F., Wegner P., Mayer HA., Benez A., Adam D., Plies E. Poly(alumosiloxanes) as matrixes for the immobilization of catalytically active ruthenium(II) complexes. Chem. Mater. 1998 10 217-225... 

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