18 solid catalyzed reactions

... chemical reactions effect of symmetrically coupled vibrations in collinear exchange reactions Chem Phys 154, 407 43 Huskey, P & Schowen, R (1983) Reaction coordinate tunneling in hydride-transfer reactions ... enzyme catalyzed reactions J Biol Chem 276, 6234–6242 59 Basran, J., Sutcliff, M.J., Scrutton, N.S (1999) Enzymatic H-transfer requires vibration driven extreme tunneling Biochemistry 38, 3 218 3222 ... chemical reactions in condensed phases J Chem Phys 114, 2910– 2 918 63 Caratzoulas, S., Mincer, J & Schwartz, S.D (2002) Identification of a protein promoting vibration in the reaction catalyzed...

Ngày tải lên: 31/03/2014, 23:20

... temperature on enzyme -catalyzed reactions Example and Application Conclusion Introduction about enzyme -catalyzed reaction • Living processes consists almost entirely of biochemical reactions Without ... of a reaction Catalysts accelerate the rates of reactions by lowering the activation energy barrier between reactants and products All chemical reactions speed up as the temperature is raised ... enough kinetic energy to undergo the reaction Since enzymes are catalysts for chemical reactions, enzyme reactions also tend to go ...

Ngày tải lên: 29/06/2014, 13:20

... for transition-metal -catalyzed reactions 169 4.4.3.1 Pd -catalyzed AAA reaction 169 4.4.3.1 Ag -catalyzed Mannich reaction 170 4.4.3.1 Rh -catalyzed1 ,4-addition 171 4.4.3.1 Pd -catalyzed 1,2-addition ... transition-metal -catalyzed reactions vii List of Tables Table 2.1 Catalytic Asymmetric Addition of Phenylboronic Acid (2-19m) to Cyclic N-Sulfonyl Aldimine 2-18a and Ketimine 2-18b 47 Table 2.2 ... of 2-18a 49 Table 2.3 Details of monitoring the reaction process of 2-18b 50 Table 2.4 Palladium -Catalyzed Asymmetric Addition of Arylboronic Acids 219m−z to Cyclic N-Sulfonyl Ketimines 2-18b−d...

Ngày tải lên: 09/09/2015, 09:59

... oxidation reactions on cellular metabolic control Metabolism 20, 187 –199 21 Harada N, Miwa GT, Walsh JS & Lu AYH (1984) Kinetic isotope effects on cytochrome P-450 -catalyzed oxidation reactions: ... 0.0059 0.25 0.31 0.14 0 .18 0.17 0.024 0.19 0.026 Used at concentration of 100 lM in all experiments b D V 8.1 8.1 7.8 7.1 7.3 V b (nmol product ⁄ nmol P450 min)1) 0. 018 0.019 0.17 0.17 0.077 ... a major factor in determining the rates of the reactions under all conditions Some shifting of the oxidations to the alternate 3-hydroxylation reactions occurs with some of the enzymes (with...

Ngày tải lên: 16/03/2014, 13:20

... mono-oxygenase Eur J Biochem 269, 183 5 184 3 14 Pilkington, S.J & Dalton, H (1990) Soluble methane monooxygenase from Methylococcus capsulatus Bath Methods Enzymol 188 , 181 –190 15 Lee, S.-K., Nesheim, ... that it was readily removed in the flow-cell experiment As dioxygen is a substrate in sMMO -catalyzed reactions, it was possible that the product that was inhibiting current flow in the static cell ... monooxygenase Science 257, 515– 518 17 Nagiev, T.M., Faradzhev, E.G & Mamedov, E.M (2001) Oxidation of methane to methanol by hydrogen peroxide under pressure Russ J Phys Chem 75, 43–48 18 George, A.R., Wilkins,...

Ngày tải lên: 17/03/2014, 09:20

... oxidation system [10 ,18, 20] It is associated with the occurrence of the different side -reactions, the lipophilicity of flavonoids or the hydrogen-bonding ability of solvents [10,11 ,18, 20] Our results ... Nova’s website under the E-book tab CHEMISTRY RESEARCH AND APPLICATIONS CHEMICAL REACTIONS IN GAS, LIQUID AND SOLID PHASES: SYNTHESIS, PROPERTIES AND APPLICATION G E ZAIKOV AND R M KOZLOWSKI ... COMMITTEE OF PUBLISHERS LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA Chemical reactions in gas, liquid, and solid phases : synthesis, properties, and application / editors, G.E Zaikov, R.M...

Ngày tải lên: 28/03/2014, 10:20

... catalysis, two representative mechanisms were proposed for phase-transfer catalyzed reactions First one is base catalyzed phase-transfer reactions Typically, under basic condition, active methylene or ... bis-(ammonium)salts 18, which resulted in the highly enantioselective alkylation of 1 .18 During the investigation, a counter-ion effect was observed: the enantioselectivity of the phase-transfer catalyzed ... catalyzed allylation of with 18b (BF4 salt) was slightly higher than with 18a (iodide salt)(Scheme 1.8) Scheme 1.8 Asymmetric alkylation of glycinate Schiff base with 18 1.2.3.4 Miscellaneous ammonium...

Ngày tải lên: 09/09/2015, 17:53

... towards various phase-transfer catalyzed reactions In the additive screening experiments, it was found that CsCl played a role of rate enhancement in the phase-transfer catalyzed conjugate additions ... 89m 18 83 87 14 2-naphthyl, Ph 89n 11 80 91 15 2-fural, Ph 89o 12 95 90 16 2-thiophenyl, Ph 89p 12 92 90 17 Me, Ph 89q 16 71 87 18 1-pyrrole, Ph 89r 12 78 92 19d Ph, 4-ClC6H4 89f 24 89 92 a Reactions ... corresponding sodium salt Details were included in experimental chapter 2.3 Pentanidium Catalyzed Conjugate Addition Reactions Enantioselective Phase-Transfer 2.3.1 Optimization of Michael addition...

Ngày tải lên: 09/09/2015, 17:53

... reactions utilized carbon–heteroatom bond-forming reactions This is the reason why new stereoselective carbon–heteroatom bond forming reactions are very important Various C-N bond formation reactions ... ee (%)d 96 52 28 K2CO3 24 87 48 Cs2CO3 18 82 50 Cs2CO3(Sat.aq.) 40 77 43 Zn2CO3 120 - Ag2CO3 15 85 11 KF 24 91 46 CsF 18 88 60 a Na2CO3 NaOH 0.2 54 33 Reactions conducted using 0.01 mmol of and ... Chem 1988, 31, 182 5 (b) Di Gregorio, G.; Pinori, M.; Verdini, A S In InnoVation and PerspectiVes in Solid- Phase Synthesis; Epton, R., Ed.; SPPC (UK) Ltd.: Birmingham, 1992; pp 311- 318 (c) Pallai,...

Ngày tải lên: 09/09/2015, 17:53

... MHz, CDCl3) δ 162.7, 66.2, 31.4, 27.8, 23.8; LRMS (ESI) m/z 318. 5 ([M-Cl-])+, HRMS (ESI) m/z 318. 2659 ([M-Cl-])+, calc for [C18H32N5+] 318. 2652 2-(((4S,5S)-1,3-dimethyl-4,5-diphenylimidazolidin-2-ylidene)amino)-1,3-dimethyl ... 127.6, 81.0, 64.7, 38.4, 35.8, 27.8, 7.67; LRMS (ESI) m/z 418. 1 (M + Na+), HRMS (ESI) m/z 418. 1997 ([M + Na+]), calc for [C24H29NO4 + Na+] 418. 1989; [α]29 = +75.2 (c 1.38, CHCl3); HPLC analysis: ... H+), HRMS (ESI) m/z 267.1497 ([M + H+]), calc for [C17H18N2O +H+] 267.1492 (4S, 5S)-1,3-Dimethyl-4,5-diphenylimidazolidin-2-imine (85): brown solid; 99% yield; 1H NMR (300 MHz, CDCl3): δ 7.17-7.14...

Ngày tải lên: 09/09/2015, 17:53

... 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 Chiral HPLC Chromatograms 030608 #440 [modi fi ed by T CH] mAU 800 mat6061-B-rac-ODH ... 12.0 Area Rel.Area mAU Height mAU*min % 5.94 n.a 649.665 218. 627 96.51 8.00 n.a 20.648 7.914 3.49 670.313 226.541 100.00 Total: ee 93% 188 030608 #438 [modified by T CH] mat6061-A-rac-ODH mAU ... 12.0 Area Rel.Area mAU Height mAU*min % 6.51 n.a 1343. 718 478.199 95.32 7.24 n.a 65.802 23.492 4.68 1409.520 501.691 100.00 Total: ee 91% 189 ...

Ngày tải lên: 09/09/2015, 17:53

... Development of Transition-Metal -Catalyzed C—S and C—C Cross-Coupling Reactions SUMMARY The transition-metal -catalyzed carbon-carbon and carbon-heteroatom bond forming reactions are important and ... synthetic organic chemistry These reactions have been widely used for a variety of cross-coupling reactions of aryl halides in the processes of C—C, C—N and C—S bond forming reactions In this dissertation, ... cross-coupling reactions Scheme 1.4: Preparation of palladium thiolato aryl complexes and its dissociation to aryl sulfides Scheme 1.5: General mechanism for the palladium -catalyzed C―S bond forming reactions...

Ngày tải lên: 10/09/2015, 15:50

... Enantioselective Claisen rearrangement reactions catalyzed by guanidinium salt 82 Scheme 1 .18 Guanidine–thiourea 85 catalyzed Henry reaction Scheme 1.19 Bifunctional guanidine 92 catalyzed 1,4-addition reaction ... for Brønsted-base Catalyzed Tandem Isomerization-Michael Reactions 74 Chapter Bicyclic Guanidine Catalyzed Asymmetric Tandem Mannich-Isomerization Reactions 4.1 Discovery ... guanidine catalyzed Michael reaction of glycinate Scheme 1.5 Enantioselective Mannich reactions of various N-Boc protected imines catalyzed by guanidine ent-22a Scheme 1.6 Guanidine ent-22d catalyzed...

Ngày tải lên: 11/09/2015, 09:17

... trichlorosilanes to aldehydes catalyzed by 17 Scheme 1.16 Addition of allyltrichlorosilane catalyzed by N-Oxide Scheme 1.17 Mo -catalyzed asymmetric allylic alkylation Scheme 1 .18 Mo -catalyzed asymmetric ... 10 1.4 Metal -Catalyzed Enantioselective Allylation Reactions - 16 1.4.1 Novel Ligands in Transition Metal Catalyzed Asymmetric Allylic Substitution and Addition Reactions ... BICYCLIC GUANIDINE CATALYZED ENANTIOSELECTIVE ALLYLIC ADDITION REACTIONS WANG JIANMIN 2011 BICYCLIC GUANIDINE CATALYZED ENANTIOSELECTIVE ALLYLIC ADDITION REACTIONS WANG JIANMIN (BSc.,...

Ngày tải lên: 12/09/2015, 09:07

... Bicyclic Guanidines Catalyzed Reactions of Anthrones 2.1 Brønsted-Base Catalyzed Diels-Alder Reaction -42 2.2 Chiral Bicyclic Guanidine Catalyzed Diels–Alder Reactions of Anthrones ... Scheme 1.17 Chiral bicyclic guanidine catalyzed Michael reactions of cyclic enones and furanone Scheme 1 .18 Chiral bicyclic guanidine catalyzed Michael reactions of alkyl trans-4-oxo-4-arylbutenoates ... dienophile catalyzed by 88a reaction catalyzed catalyzed by guanidine-thiourea Diels–Alder reaction of Scheme 2.5 Diels–Alder reaction of 3-hydroxy-2-pyrone catalyzed by 91 Scheme 2.6 Asymmetric base-catalyzed...

Ngày tải lên: 12/09/2015, 10:17

... 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) Catalyzed Michael Reactions 2.1 The Synthetic Utility of TBD 31 2.2 TBD Catalyzed Michael Reactions -32 ... 1.16 Henry reaction catalyzed by homochiral guanidine Scheme 1.17 Diastereoselective Henry reaction catalyzed by chiral guanidines Scheme 1 .18 Diastereoselective Henry reaction catalyzed by a guanidine-thiourea ... that are suitable for Michael and Michael-type reactions using TBD as the catalyst 2.2 TBD Catalyzed Michael Reactions 2.2.1 Various organobases catalyzed Michael reaction of cyclopentenone and...

Ngày tải lên: 12/09/2015, 10:17

... Asymmetric Henry reactions.   Scheme 1.3  Diastereoselective Henry reaction catalyzed by guanidine 3a.  Scheme 1.4  Guanidine 4a catalyzed asymmetric Henry reactions.   Scheme 1.5  Asymmetric Henry reactions of various aldehydes and nitroalkanes  ... List of Figures  List of Abbreviations  Chapter 1 Chiral Guanidines Catalyzed Enantioselective Reactions Chiral Guanidines Catalyzed Enantioselective Reactions 1  1.1 Introduction  2  1.2 Chiral Guanidines as Asymmetric Catalysts  ... Chapter 3 Kinetic Studies of Enantioselective Protonation Reactions Catalyzed by Chiral Bicyclic Guanidine  Kinetic Studies of Enantioselective Protonation Reactions Catalyzed by Chiral Bicyclic  Guanidine ...

Ngày tải lên: 12/09/2015, 10:17

... Asymmetric phospha-Michael reactions 1.1.1 Asymmetric phospha-Michael reactions through chiral starting materials and chiral auxiliaries Asymmetric versions of phospha-Michael reactions mainly deal ... Scheme 1.12 Organonickel complex catalyzed enantioselective phospha-Michael addition of secondary phosphines 1.1.3 Organocatalyst catalyzed asymmetric phospha-Michael reactions Recently, Melchiorre ... probably the most prominent ligands, in terms of structural and electronic diversity in metal -catalyzed reactions2 and nucleophilic phosphine organocatalysis.3 Molecules containing a phosphonic [P(O)(OH)2],...

Ngày tải lên: 14/09/2015, 08:38

... Scheme 2.2C TBD catalyzed three-component phospha-Michael reactions of diphenyl phosphine oxide 2.2 Synthesis of chiral bicyclic guanidines and their application in enantioselective reactions It ... bicyclic guanidine catalyzed Michael reactions of ethyl maleimide and 1, 3-diketones, β-keto esters, dithiomalonates The guanidine 114b was found to be a catalyst for asymmetric Michael reactions (Scheme ... regioselectivities were obtained in all examples 2.3 Bicyclic guanidine -catalyzed phospha-Michael enantioselective reactions The phospha-Michael reactions employing phosphorus nucleophiles such as phosphonates...

Ngày tải lên: 14/09/2015, 08:38

... 10eq K2CO3 Ph 182 Bn O P OR Ph OR O P Bn NHTs NHTs Ph sy n -183 anti- 183 entrya 183 [R] time/hb ee of 183 /%c drd 183 a[2-MeOC6H4CH2] 24 45; 67 2:1 183 b[2-NO2C6H4CH2] 24 70; 30 2:1 183 c[2-NpCH2] ... reaction NHTs Ar -180 a-g syn entrya Ar syn -180 time/h yield/%b dr c ee of syn -180 /%d Ph 180 a 39 83 6:1 94 2e 4-FC6H5 180 b 35 90 6:1 90 3e 4-ClC6H5 180 c 108 90 4:1 92 4e 4-MeC6H5 180 d 100 85 4:1 ... Ph syn -180 i-m Yield/%a drb ee of syn -180 [%]c entry 179 [R] 179b[2-NpCH2] 180 i 38 92 6.5:1 94 179c[4-CF3Ph CH2] 180 j 36 92 16:1 94 179d[4-NO2PhCH2] 180 k 36 90 5.5:1 89 179e[4-MePhCH2] 180 l 43...

Ngày tải lên: 14/09/2015, 08:38