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Reetz MT, Ma JA, Goddard R. Binol-Derived Monodentate Phosphites and Phosphoramidites with Phosphorus Stereogenic Centers: Novel Ligands for Transition-Metal Catalysis. Angew Chem Int Ed Engl 2005; 44:412-5. [PMID: 15624174 DOI: 10.1002/anie.200461624] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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227
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Bernsmann H, van den Berg M, Hoen R, Minnaard AJ, Mehler G, Reetz MT, De Vries JG, Feringa BL. PipPhos and MorfPhos: Privileged Monodentate Phosphoramidite Ligands for Rhodium-Catalyzed Asymmetric Hydrogenation. J Org Chem 2005; 70:943-51. [PMID: 15675853 DOI: 10.1021/jo048374o] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A library of 20 monodentate phosphoramidite ligands has been prepared and applied in rhodium-catalyzed asymmetric hydrogenation. This resulted in the identification of two ligands, PipPhos and MorfPhos, that afford excellent and in several cases unprecedented enantioselectivities in the hydrogenation of N-acyldehydroamino acid esters, dimethyl itaconate, acyclic N-acylenamides, and cyclic N-acylenamides. In addition, a method for the parallel enantioselectivity determination of eight acylated amines is presented.
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228
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Reetz MT, Li X. Rhodium-Catalyzed Enantioselective Hydrogenation of β,β-Disubstituted α-Acetamido Acrylates Using Cheap Monodentate P-Ligands. SYNTHESIS-STUTTGART 2005. [DOI: 10.1055/s-2005-918460] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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229
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Reetz MT, Schulenburg H, Lopez M, Spliethoff B, Tesche B. Platinum-Nanoparticles on Different Types of Carbon Supports: Correlation of Electrocatalytic Activity with Carrier Morphology. Chimia (Aarau) 2004. [DOI: 10.2533/000942904777677083] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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230
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Reetz MT, Hütte S, Goddard R. Synthetic and mechanistic aspects of anionic polymerization of (METH)acrylates initiated by metal-free salts of CH-acidic compounds. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.610080406] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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231
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Reetz MT, Brunner B, Schneider T, Schulz F, Clouthier CM, Kayser MM. Directed Evolution as a Method To Create Enantioselective Cyclohexanone Monooxygenases for Catalysis in Baeyer–Villiger Reactions. Angew Chem Int Ed Engl 2004; 43:4075-8. [PMID: 15300699 DOI: 10.1002/anie.200460272] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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232
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Reetz MT, Daligault F, Brunner B, Hinrichs H, Deege A. Directed Evolution of Cyclohexanone Monooxygenases: Enantioselective Biocatalysts for the Oxidation of Prochiral Thioethers. Angew Chem Int Ed Engl 2004; 43:4078-81. [PMID: 15300700 DOI: 10.1002/anie.200460311] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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233
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Reetz MT, Daligault F, Brunner B, Hinrichs H, Deege A. Directed Evolution of Cyclohexanone Monooxygenases: Enantioselective Biocatalysts for the Oxidation of Prochiral Thioethers. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200460311] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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234
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Reetz MT, Brunner B, Schneider T, Schulz F, Clouthier CM, Kayser MM. Directed Evolution as a Method To Create Enantioselective Cyclohexanone Monooxygenases for Catalysis in Baeyer–Villiger Reactions. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200460272] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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235
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Reetz MT, Mehler G, Meiswinkel A. Mixtures of chiral monodentate phosphites, phosphonites and phosphines as ligands in Rh-catalyzed hydrogenation of N-acyl enamines: extension of the combinatorial approach. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.04.038] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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236
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Reetz MT, Tielmann P, Eipper A, Ross A, Schlotterbeck G. A high-throughput NMR-based ee-assay using chemical shift imaging. Chem Commun (Camb) 2004:1366-7. [PMID: 15179467 DOI: 10.1039/b403249g] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The throughput of a previously described NMR-based -assay has been increased by a factor of at least 4 as a consequence of adapting the system to chemical shift imaging; by using a 19-capillary system the enantiomeric purity of 5600 samples can be measured per day.
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237
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Reetz MT. Controlling the enantioselectivity of enzymes by directed evolution: practical and theoretical ramifications. Proc Natl Acad Sci U S A 2004; 101:5716-22. [PMID: 15079053 PMCID: PMC395973 DOI: 10.1073/pnas.0306866101] [Citation(s) in RCA: 240] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2003] [Indexed: 11/18/2022] Open
Abstract
A fundamentally new approach to asymmetric catalysis in organic chemistry is described based on the in vitro evolution of enantioselective enzymes. It comprises the appropriate combination of gene mutagenesis and expression coupled with an efficient high-throughput screening system for evaluating enantioselectivity (enantiomeric excess assay). Several such cycles lead to a "Darwinistic" process, which is independent of any knowledge concerning the structure or the mechanism of the enzyme being evolved. The challenge is to choose the optimal mutagenesis methods to navigate efficiently in protein sequence space. As a first example, the combination of error-prone mutagenesis, saturation mutagenesis, and DNA-shuffling led to a dramatic enhancement of enantioselectivity of a lipase acting as a catalyst in the kinetic resolution of a chiral ester. Mutations at positions remote from the catalytically active center were identified, a surprising finding, which was explained on the basis of a novel relay mechanism. The scope and limitations of the method are discussed, including the prospect of directed evolution of stereoselective hybrid catalysts composed of robust protein hosts in which transition metal centers have been implanted.
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238
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Bocola M, Otte N, Jaeger KE, Reetz MT, Thiel W. Learning from Directed Evolution: Theoretical Investigations into Cooperative Mutations in Lipase Enantioselectivity. Chembiochem 2004; 5:214-23. [PMID: 14760743 DOI: 10.1002/cbic.200300731] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Molecular modeling with classical force-fields has been used to study the reactant complex and the tetrahedral intermediate in lipase-catalyzed ester hydrolysis in 20 enzyme/substrate combinations. The R and S enantiomers of alpha-methyldecanoic acid ester served as substrates for the wild-type lipase from Pseudomonas aeruginosa and nine selected mutants. After suitable preparation of initial structures from an available wild-type crystal structure, each system was subjected to 1 ns CHARMM force-field molecular dynamics simulations. The resulting geometric and energetic changes allow interpretation of some experimentally observed effects of mutations, particularly with regard to the "hot spots" at residues 155 and 162. The replacement S155F enhances S enantiopreference through a steric relay involving Leu162. The double mutation S53P + L162G improves S enantioselectivity by creating a new binding pocket for the S enantiomer with an additional stabilizing hydrogen bond to His83. The simulations provide insight into remote and cooperative effects of mutations.
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239
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Abstract
Activated and non-activated aryl bromides undergo smooth ligand-less Heck reactions, provided low amounts of palladium salts such as Pd(OAc)2 are used (ideally 0.01-0.1 mol%). This industrially viable process appears to involve palladium nanoparticles.
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240
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241
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Reetz MT, Wiesenhöfer W. Liquid poly(ethylene glycol) and supercritical carbon dioxide as a biphasic solvent system for lipase-catalyzed esterification. Chem Commun (Camb) 2004:2750-1. [PMID: 15568099 DOI: 10.1039/b412049c] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The biphasic solvent system composed of poly(ethylene glycol)(PEG) and supercritical carbon dioxide (scCO2) is ideally suited for the lipase-catalyzed acylation of alcohols; batch or continuous flow acylations are possible, scCO2 being used to extract the products.
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243
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Reetz MT, Ostarek R, Piejko KE, Arlt D, Bömer B. Group Transfer Polymerization of Acrylic Acid Esters with Alkylthio- or Arylthiosilanes as Initiators. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/anie.198611081] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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244
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Reetz MT. Select protocols of high-throughput ee-screening systems for assaying enantioselective enzymes. Methods Mol Biol 2003; 230:283-90. [PMID: 12824590 DOI: 10.1385/1-59259-396-8:283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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245
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Reetz MT. An overview of high-throughput screening systems for enantioselective enzymatic transformations. Methods Mol Biol 2003; 230:259-82. [PMID: 12824589 DOI: 10.1385/1-59259-396-8:259] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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246
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Reetz MT, Goossen LJ, Meiswinkel A, Paetzold J, Jensen JF. Enantioselective Rh-catalyzed hydrogenation of vinyl carboxylates with monodentate phosphite ligands. Org Lett 2003; 5:3099-101. [PMID: 12916991 DOI: 10.1021/ol035076p] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Alkyl-substituted vinylcarboxylates, which normally show poor enantioselectivity in Rh-catalyzed hydrogenation with traditional chiral diphosphines, undergo highly enantioselective reactions with BINOL- and carbohydrate-based monophosphite ligands.
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247
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Tielmann P, Boese M, Luft M, Reetz MT. A practical high-throughput screening system for enantioselectivity by using FTIR spectroscopy. Chemistry 2003; 9:3882-7. [PMID: 12916113 DOI: 10.1002/chem.200304885] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
For the first time FTIR spectroscopy has been applied to the measurement of enantiomeric purity. The underlying concept is based on the use of pseudo-enantiomers that are (13)C-labeled at appropriate positions. Upon applying Lambert-Beer's law in the determination of the concentrations of both enantiomers, the ee values are accessible, accuracy to within +/-5 % of the true values being possible. The application of a commercially available high-throughput FTIR system results in a slightly decreased accuracy (+/-7% for the ee values), but this allows a throughput of up to 10000 samples per day. The method is of interest in the area of combinatorial symmetric catalysis and directed evolution of enantioselective enzymes.
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248
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Reetz MT, Lopez M, Grünert W, Vogel W, Mahlendorf F. Preparation of Colloidal Nanoparticles of Mixed Metal Oxides Containing Platinum, Ruthenium, Osmium, and Iridium and Their Use as Electrocatalysts. J Phys Chem B 2003. [DOI: 10.1021/jp027785a] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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249
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Reetz MT, Mehler G. Mixtures of chiral and achiral monodentate ligands in asymmetric Rh-catalyzed olefin hydrogenation: reversal of enantioselectivity. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)00976-6] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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250
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Reetz MT, Sell T, Goddard R. Chiral Phosphoric Acid Diesters as Ligands in Asymmetric Transition Metal Catalyzed Hydrogenation. Chimia (Aarau) 2003. [DOI: 10.2533/000942903777679316] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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