The In Situ Enzymatic Screening (ISES) Approach to Reaction Discovery and Catalyst Identification

Robert A. Swyka1, David B. Berkowitz1

1 Department of Chemistry, University of Nebraska, Lincoln, Nebraska
Publication Name:  Current Protocols in Chemical Biology
Unit Number:   
DOI:  10.1002/cpch.30
Online Posting Date:  December, 2017
GO TO THE FULL TEXT: PDF or HTML at Wiley Online Library

Abstract

The importance of discovering new chemical transformations and/or optimizing catalytic combinations has led to a flurry of activity in reaction screening. The in situ enzymatic screening (ISES) approach described here utilizes biological tools (enzymes/cofactors) to advance chemistry. The protocol interfaces an organic reaction layer with an adjacent aqueous layer containing reporting enzymes that act upon the organic reaction product, giving rise to a spectroscopic signal. ISES allows the experimentalist to rapidly glean information on the relative rates of a set of parallel organic/organometallic reactions under investigation, without the need to quench the reactions or draw aliquots. In certain cases, the real‐time enzymatic readout also provides information on sense and magnitude of enantioselectivity and substrate specificity. This article contains protocols for single‐well (relative rate) and double‐well (relative rate/enantiomeric excess) ISES, in addition to a colorimetric ISES protocol and a miniaturized double‐well procedure. © 2017 by John Wiley & Sons, Inc.

Keywords: catalysis; enzymatic screening; reaction discovery; metal‐ligand combinations; UV/vis spectrophotometry

     
 
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Table of Contents

  • Introduction
  • Basic Protocol 1: In Situ Enzymatic Screening (ISES) Method (UV/VIS Readout; Single Well Per Catalyst Screened)
  • Basic Protocol 2: Colorimetric In Situ Enzymatic Screening (ISES) Method (Visible Color Change; Single Well Per Catalyst Screened)
  • Basic Protocol 3: In Situ Enzymatic Screening (ISES) Assay Detecting Chiral Reaction Products (UV/VIS Readout; Two Wells Per Catalyst Screened)
  • Alternate Protocol 1: Expansion of to Screen two Substrate Candidates in Parallel (Four Wells Per Catalyst Screened): Parallel Multiple Substrate % EE Determination
  • Basic Protocol 4: Miniature ISES Assay Detecting Chiral Reaction Products (Two Wells Per Substrate; Four Wells Per Catalyst)
  • Commentary
  • Literature Cited
  • Figures
  • Tables
     
 
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Materials

Basic Protocol 1: In Situ Enzymatic Screening (ISES) Method (UV/VIS Readout; Single Well Per Catalyst Screened)

  Materials
  • Yeast alcohol dehydrogenase (ADH) lyophilized powder (EC 1.1.1.1; Sigma‐Aldrich)
  • Yeast aldehyde dehydrogenase (AlDH) lyophilized powder (EC 1.2.1.5; Boehringer‐Mannheim)
  • β‐NAD+ (free acid; Sigma‐Aldrich)
  • β‐NADH (disodium salt; Sigma‐Aldrich)
  • Ethanol
  • Acetaldehyde
  • Sodium phosphate, monobasic and dibasic salts
  • Sodium pyrophosphate
  • THF/hexane/toluene (2:1:1; solvent for upper organic phase)
  • Ni(cod) 2
  • Triphenyl phosphine (PPh 3)
  • Substrate of interest (allylic carbonate bearing an appropriately positioned nucleophile, e.g., carbamate nitrogen; see Figure )
  • Lithium hexamethyldisilazide (LiHMDS)
  • Rubber septa (13 mm OD, with neck trimmed off; these fit 1‐ml cuvettes snuggly)
  • UV spectrophotometer (6 to 12 multi‐cell positioner useful but not necessary; Shimadzu UV‐2101PC or Shimadzu UV‐2401PC used for this protocol; Cary: 12‐cell positioner)
  • Quartz cuvettes (1 ml each)
  • Components for organic reaction of interest (example reaction: Intramolecular allylic amination; specific conditions for Ni cuvette in Figure )
NOTE: This procedure describes ISES with an upper organic phase; subsequent protocols make use of a lower organic phase, typically generated by utilizing a significant percentage of a chlorinated solvent. See the protocols that follow and the Troubleshooting section for more insight into organic layer selection. At the outset, care should always be taken to position the phase partition in the cuvette so that the UV beam passes squarely through the aqueous reporting layer.

Basic Protocol 2: Colorimetric In Situ Enzymatic Screening (ISES) Method (Visible Color Change; Single Well Per Catalyst Screened)

  Materials
  • Alcohol oxidase (AO; EC 1.1.3.13; from Hansenula sp. lyophilized powder; Sigma‐Aldrich)
  • Peroxidase (EC 1.11.1.7; from horseradish, HRP, Type VI, lyophilized powder; Sigma‐Aldrich)
  • 2,2′‐Azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS; Sigma‐Aldrich)
  • Methanol
  • Hydrogen peroxide (aqueous, 30%, w/w)
  • Potassium phosphate, monobasic and dibasic salts
  • 1,1,2‐Trichloroethane (TCE)
  • Tetrahydrofuran (THF)
  • Components for organic reaction of interest (example reaction: (pseudo)halometallation‐carbocyclization; see Figure )
  • Lithium halide (LiF, LiCl, LiBr) or pseudohalide (e.g., LiSCN, LiOCN, LiCN)
  • Transition metal (TM) catalyst candidates (64 TM complexes screened here with [Rh(O 2CCF 3) 2] 2 and Cl 2Pd(NCPh) 2 being among the most effective catalysts depending upon substrate and halide/pseudohalide; Friest et al., ; Ginotra, Friest, & Berkowitz, )
  • Substrates of interest (in this example, 5‐ and 6‐exo‐trig ester and 5‐exo‐trig ether substrates 1 to 3 were used; all are outfitted with an allylic methyl carbonate functionality; Figure )
  • UV/vis spectrophotometer (Shimadzu UV‐2101PC or Shimadzu UV‐2401PC used for this protocol)
  • Quartz cuvettes (1 ml)
  • Multichannel pipetter, e.g., Eppendorf (Thermo Fisher Scientific) or Rainin (Mettler‐Toledo)
  • Plastic or Plexiglass 96‐well tray (Thermo Fisher Scientific) or custom‐fabricated, as needed, depending upon culture tube dimensions (Plexiglass is poly(methyl methacrylate) and is easily machined to make custom trays)
  • Disposable cell culture tubes (6 × 50 mm utilized here; Thermo Fisher Scientific)

Basic Protocol 3: In Situ Enzymatic Screening (ISES) Assay Detecting Chiral Reaction Products (UV/VIS Readout; Two Wells Per Catalyst Screened)

  Materials
  • β‐NAD+ (Sigma‐Aldrich)
  • β‐NADP+ (Sigma‐Aldrich)
  • Horse liver alcohol dehydrogenase (HLADH; EC 1.1.1.1; Sigma‐Aldrich)
  • Thermoanaerobium brockii alcohol dehydrogenase (TBADH; EC 1.1.1.2; Sigma‐Aldrich)
  • Sodium phosphate, monobasic and dibasic salts
  • 1,2‐Propanediol (R, S, and racemic)
  • Sodium pyrophosphate
  • Components for organic reaction of interest (example reaction: Hydrolytic kinetic resolution of epoxides employing Co(III)‐salen catalysts designed and synthesized in the Berkowitz Lab)
  • Chloroform or dichloromethane for organic layer
  • Epoxide substrate (e.g., (±)‐propylene oxide, (±)‐hexene oxide)
  • Co(III)‐salen catalyst array
  • UV/vis spectrophotometer
  • 1‐ml quartz cuvettes

Alternate Protocol 1: Expansion of to Screen two Substrate Candidates in Parallel (Four Wells Per Catalyst Screened): Parallel Multiple Substrate % EE Determination

  Materials
  • β‐NAD+ (free acid; Sigma‐Aldrich)
  • β‐NADP+ (Sigma‐Aldrich)
  • Reporting enzymes (KRED 23, 107, 119 enzymes, Codexis; TBADH, Sigma‐Aldrich)
  • (R)‐ and (S)‐1,2‐Propanediol (or product of interest)
  • (R)‐ and (S)‐1,2‐Hexanediol (or product of interest)
  • (±)‐1‐Hexene oxide
  • (±)‐Propylene oxide
  • Sodium pyrophosphate
  • Sodium phosphate, monobasic and dibasic salts
  • Chloroform
  • Co(III)‐salen catalyst array
  • UV/vis spectrophotometer with micromulticell capability
  • 16‐well quartz micromulticell (Shimadzu or other supplier)
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library

Figures

Videos

Literature Cited

Literature Cited
  Abato, P., & Seto, C. T. (2001). EMDee: An enzymatic method for determining enantiomeric excess. Journal of the American Chemical Society, 123, 9206–9207. doi: 10.1021/ja016177q
  Applegate, G. A., Cheloha, R. W., Nelson, D. L., & Berkowitz, D. B. (2011). A new dehydrogenase from Clostridium acetobutylicum for asymmetric synthesis: Dynamic reductive kinetic resolution entry into the Taxotère side chain. Chemical Communications, 47, 2420–2422. doi: 10.1039/C0CC04585C
  Bentley, K. W., Proano, D., & Wolf, C. (2016a). Chirality imprinting and direct asymmetric reaction screening using a stereodynamic Bronsted/Lewis acid receptor. Nature Communications, 7, 12539. doi: 10.1038/ncomms12539
  Bentley, K. W., Zhang, P., & Wolf, C. (2016b). Miniature high‐throughput chemosensing of yield, ee, and absolute configuration from crude reaction mixtures. Science Advances, 2, e1501162. doi: 10.1126/sciadv.1501162
  Berkowitz, D. B., Bose, M., & Choi, S. (2002). In situ enzymatic screening (ISES): A tool for catalyst discovery and reaction development. Angewandte Chemie (International ed. in English), 41, 1603–1607. doi: 10.1002/1521‐3773(20020503)41:9%3c1603::AID‐ANIE1603%3e3.0.CO;2‐D
  Berkowitz, D. B., Jahng, W.‐J., & Pedersen, M. L. (1996a). α–Vinyllysine and α‐vinylarginine are time‐dependent inhibitors of their cognate decarboxylases. Bioorganic & Medicinal Chemistry Letters, 6, 2151–2156. doi: 10.1016/0960‐894X(96)00366‐6
  Berkowitz, D. B., & Maiti, G. (2004). Following an ISES lead: The first examples of asymmetric Ni(0)‐mediated allylic amination. Organic Letters, 6, 2661–2664. doi: 10.1021/ol049159x
  Berkowitz, D. B., McFadden, J. M., Chisowa, E., & Semerad, C. L. (2000). Organoselenium‐based entry into versatile, α‐(2‐tributylstannyl)vinyl amino acids in scalemic form: A new route to vinyl stannanes. Journal of the American Chemical Society, 122, 11031–11032. doi: 10.1021/ja0055110
  Berkowitz, D. B., Pedersen, M. L., & Jahng, W.‐J. (1996b). Synthesis of higher α‐chlorovinyl and α‐bromovinyl amino acids: The amino protecting group determines the reaction course. Tetrahedron Letters, 37, 4309–4312. doi: 10.1016/0040‐4039(96)00832‐5
  Berkowitz, D. B., Pumphrey, J. A., & Shen, Q. (1994). Enantiomerically enriched α‐vinyl amino acids via lipase‐mediated reverse transesterification. Tetrahedron Letters, 35, 8743–8746. doi: 10.1016/S0040‐4039(00)78486‐3
  Berkowitz, D. B., Shen, W., & Maiti, G. (2004). In situ enzymatic screening (ISES) of P, N‐ligands for Ni(0)‐mediated asymmetric intramolecular allylic amination. Tetrahedron: Asymmetry, 15, 2845–2851. doi: 10.1016/j.tetasy.2004.06.052
  Berkowitz, D. B., & Smith, M. K. (1996). A convenient synthesis of l‐ α‐vinylglycine from l‐homoserine lactone. Synthesis, 39–41. doi: 10.1055/s‐1996‐4177
  Bertozzi, C. R., Chang, C. J., Chattopadhyay, A., Stockwell, B. R., Schultz, C., Butcher, R. A., … Prescher, J. A. (2015). Voices of chemical biology. Nature Chemical Biology, 11, 378–379. doi: 10.1038/nchembio.1820
  Buitrago Santanilla, A., Regalado, E. L., Pereira, T., Shevlin, M., Bateman, K., Campeau, L.‐C., … Dreher, S. D. (2015). Nanomole‐scale high‐throughput chemistry for the synthesis of complex molecules. Science, 347, 49–53. doi: 10.1126/science.1259203
  Chan, A. I., McGregor, L. M., & Liu, D. R. (2015). Novel selection methods for DNA‐encoded chemical libraries. Current Opinion in Chemical Biology, 26, 55–61. doi: 10.1016/j.cbpa.2015.02.010
  Collins, K. D., Gensch, T., & Glorius, F. (2014). Contemporary screening approaches to reaction discovery and development. Nature Chemical, 6, 859–871. doi: 10.1038/nchem.2062
  Copeland, G. T., & Miller, S. J. (1999). A chemosensor‐based approach to catalyst discovery in solution and on solid support. Journal of the American Chemical Society, 121, 4306–4307. doi: 10.1021/ja984139+
  Créminon, C., & Taran, F. (2015). Enzyme immunoassays as screening tools for catalysts and reaction discovery. Chemical Communications, 51, 7996–8009. doi: 10.1039/C5CC00599J
  De los Santos, Z. A., & Wolf, C. (2016). Chiroptical asymmetric reaction screening via multicomponent self‐assembly. Journal of the American Chemical Society, 138, 13517–13520. doi: 10.1021/jacs.6b08892
  Debler, E. W., Kaufmann, G. F., Meijler, M. M., Heine, A., Mee, J. M., Pljevaljčić, G., … Janda, K. D. (2008). Deeply inverted electron‐hole recombination in a luminescent antibody‐stilbene complex. Science, 319, 1232–1235. doi: 10.1126/science.1153445
  Dey, S., Karukurichi, K. R., Shen, W., & Berkowitz, D. B. (2005). Double‐cuvette ISES: In situ estimation of enantioselectivity and relative rate for catalyst screening. Journal of the American Chemical Society, 127, 8610–8611. doi: 10.1021/ja052010b
  Dey, S., Powell, D. R., Hu, C., & Berkowitz, D. B. (2007). “Cassette” in situ enzymatic screening identifies complementary chiral scaffolds for hydrolytic kinetic resolution across a range of epoxides. Angewandte Chemie (International ed. in English), 46, 7010–7014. doi: 10.1002/anie.200701280
  Ebner, C., Muller, C. A., Markert, C., & Pfaltz, A. (2011). Determining the enantioselectivity of chiral catalysts by mass spectrometric screening of their racemic forms. Journal of the American Chemical Society, 133, 4710–4713. doi: 10.1021/ja111700e
  Feagin, T. A., Olsen, D. P., Headman, Z. C., & Heemstra, J. M. (2015). High‐throughput enantiopurity analysis using enantiomeric DNA‐based sensors. Journal of the American Chemical Society, 137, 4198–4206. doi: 10.1021/jacs.5b00923
  Finn, M. G. (2002). Emerging methods for the rapid determination of enantiomeric excess. Chirality, 14, 534–540. doi: 10.1002/chir.10101
  Ford, D. D., Nielsen, L. P. C., Zuend, S. J., & Jacobsen, E. N. (2013). Mechanistic basis for high stereoselectivity and broad substrate scope in the (salen)Co(III)‐catalyzed hydrolytic kinetic resolution. Journal of the American Chemical Society, 135, 15595–15608. doi: 10.1021/ja408027p
  Friest, J. A., Broussy, S., Chung, W. J., & Berkowitz, D. B. (2011). Combinatorial catalysis employing a visible enzymatic beacon in real time: Synthetically versatile (pseudo)halometalation/carbocyclizations. Angewandte Chemie (International ed. in English), 50, 8895–8899. doi: 10.1002/anie.201103365
  Friest, J. A., Maezato, Y., Broussy, S., Blum, P., & Berkowitz, D. B. (2010). Use of a robust dehydrogenase from an archael hyperthermophile in asymmetric catalysis‐Dynamic reductive kinetic resolution entry into (S)‐Profens. Journal of the American Chemical Society, 132, 5930–5931. doi: 10.1021/ja910778p
  Ginotra, S. K., Friest, J. A., & Berkowitz, D. B. (2012). Halocarbocyclization entry into the oxabicyclo[4.3.1]decyl exomethylene‐ δ‐lactone cores of linearifolin and zaluzanin A: Exploiting combinatorial catalysis. Organic Letters, 14, 968–971. doi: 10.1021/ol203088g
  Goodell, J. R., McMullen, J. P., Zaborenko, N., Maloney, J. R., Ho, C.‐X., Jensen, K. F., … Beeler, A. B. (2009). Development of an automated microfluidic reaction platform for multidimensional screening: Reaction discovery employing bicyclo[3.2.1]octanoid scaffolds. The Journal of Organic Chemistry, 74, 6169–6180. doi: 10.1021/jo901073v
  Hamberg, A., Lundgren, S., Penhoat, M., Moberg, C., & Hult, K. (2006). High‐throughput enzymatic method for enantiomeric excess determination of O‐acetylated cyanohydrins. Journal of the American Chemical Society, 128, 2234–2235. doi: 10.1021/ja058474r
  Isenegger, P. G., Baechle, F., & Pfaltz, A. (2016). Asymmetric Morita‐Baylis‐Hillman reaction: Catalyst development and mechanistic insights based on mass spectrometric back‐reaction screening. Chemistry ‐ A European Journal, 22, 17595–17599. doi: 10.1002/chem.201604616
  Jo, H. H., Lin, C.‐Y., & Anslyn, E. V. (2014). Rapid optical methods for enantiomeric excess analysis: From enantioselective indicator displacement assays to exciton‐coupled circular dichroism. Accounts of Chemical Research, 47, 2212–2221. doi: 10.1021/ar500147x
  Jung, E., Kim, S., Kim, Y., Seo, S. H., Lee, S. S., Han, M. S., & Lee, S. (2011). A colorimetric high‐throughput screening method for palladium‐catalyzed coupling reactions of aryl iodides using a gold nanoparticle‐based iodide‐selective probe. Angewandte Chemie (International ed. in English), 50, 4386–4389. doi: 10.1002/anie.201100378
  Kanan, M. W., Rozenman, M. M., Sakurai, K., Snyder, T. M., & Liu, D. R. (2004). Reaction discovery enabled by DNA‐templated synthesis and in vitro selection. Nature, 431, 545–549. doi: 10.1038/nature02920
  Karukurichi, K. R., De la Salud‐Bea, R., Jahng, W. J., & Berkowitz, D. B. (2007). Examination of the new α‐(2′Z‐fluoro)vinyl trigger with lysine decarboxylase: The absolute stereochemistry dictates the reaction course. Journal of the American Chemical Society, 129, 258–259. doi: 10.1021/ja067240k
  Karukurichi, K. R., Fei, X., Swyka, R. A., Broussy, S., Shen, W., Dey, S., … Berkowitz, D. B. (2015). Mini‐ISES identifies promising carbafructopyranose‐based salens for asymmetric catalysis: Tuning ligand shape via the anomeric effect. Science Advances, 1, e1500066. doi: 10.1126/sciadv.1500066
  Kleiner, R. E., Dumelin, C. E., & Liu, D. R. (2011). Small‐molecule discovery from DNA‐encoded chemical libraries. Chemical Society Reviews, 40, 5707–5717. doi: 10.1039/c1cs15076f
  Kolodych, S., Rasolofonjatovo, E., Chaumontet, M., Nevers, M. C., Créminon, C., & Taran, F. (2013). Discovery of chemoselective and biocompatible reactions using a high‐throughput immunoassay screening. Angewandte Chemie (International ed. in English), 52, 12056–12060. doi: 10.1002/anie.201305645
  Leung, D., & Anslyn, E. V. (2011). Rapid determination of enantiomeric excess of α‐chiral cyclohexanones using circular dichroism spectroscopy. Organic Letters, 13, 2298–2301. doi: 10.1021/ol2004885
  Leung, D., Folmer‐Andersen, J. F., Lynch, V. M., & Anslyn, E. V. (2008). Using enantioselective indicator displacement assays to determine the enantiomeric excess of α‐amino acids. Journal of the American Chemical Society, 130, 12318–12327. doi: 10.1021/ja803806c
  Leung, D., Kang, S. O., & Anslyn, E. V. (2012). Rapid determination of enantiomeric excess: A focus on optical approaches. Chemical Society Reviews, 41, 448–479. doi: 10.1039/C1CS15135E
  Lichtor, P. A., & Miller, S. J. (2011). One‐bead‐one‐catalyst approach to aspartic acid‐based oxidation catalyst discovery. ACS Combinatorial Science, 13, 321–326. doi: 10.1021/co200010v
  Lin, C.‐Y., Giuliano, M. W., Ellis, B. D., Miller, S. J., & Anslyn, E. V. (2016). From substituent effects to applications: Enhancing the optical response of a four‐component assembly for reporting ee values. Chemical Science, 7, 4085–4090. doi: 10.1039/C5SC04629G
  Loch, J. A., & Crabtree, R. H. (2001). Rapid screening and combinatorial methods in homogeneous organometallic catalysis. Pure and Applied Chemistry, 73, 119–128. doi: 10.1351/pac200173010119
  Loskyll, J., Stoewe, K., & Maier, W. F. (2012). Infrared thermography as a high‐throughput tool in catalysis research. ACS Combinatorial Science, 14, 295–303. doi: 10.1021/co200168s
  Malik, G., Swyka, R. A., Tiwari, V. K., Fei, X., Applegate, G. A., & Berkowitz, D. B. (2017). A thiocyanopalladation/carbocyclization transformation identified through enzymatic screening: Tandem C‐SCN and C‐C bond formation. Chemical Science. Advance online publication. doi: 10.1039/C7SC04083K.
  Matsushita, M., Yoshida, K., Yamamoto, N., Wirsching, P., Lerner, R. A., & Janda, K. D. (2003). High‐throughput screening by using a blue‐fluorescent antibody sensor. Angewandte Chemie (International ed. in English), 42, 5984–5987. doi: 10.1002/anie.200352793
  McNally, A., Prier, C. K., & MacMillan, D. W. C. (2011). Discovery of an α‐amino C‐H arylation reaction using the strategy of accelerated serendipity. Science, 334, 1114–1117. doi: 10.1126/science.1213920
  Mei, X., & Wolf, C. (2006). Determination of enantiomeric excess and concentration of unprotected amino acids, amines, amino alcohols, and carboxylic acids by competitive binding assays with a chiral scandium complex. Journal of the American Chemical Society, 128, 13326–13327. doi: 10.1021/ja0636486
  Montavon, T. J., Li, J., Cabrera‐Pardo, J. R., Mrksich, M., & Kozmin, S. A. (2012). Three‐component reaction discovery enabled by mass spectrometry of self‐assembled monolayers. Nature Chemistry, 4, 45–51. doi: 10.1038/nchem.1212
  Mueller, C. A., Markert, C., Teichert, A. M., & Pfaltz, A. (2009). Mass spectrometric screening of chiral catalysts and catalyst mixtures. Chemical Communications, 1607–1618. doi: 10.1039/b822382c
  Onaran, M. B., & Seto, C. T. (2003). Using a lipase as a high‐throughput screening method for measuring the enantiomeric excess of allylic acetates. The Journal of Organic Chemistry, 68, 8136–8141. doi: 10.1021/jo035067u
  Pfaltz, A. (2010). Design and screening of chiral catalysts. Chimia, 64, 860–862.
  Reetz, M. T. (2002). New methods for the high‐throughput screening of enantioselective catalysts and biocatalysts. Angewandte Chemie (International ed. in English), 41, 1335–1338. doi: 10.1002/1521‐3773(20020415)41:8%3c1335::AID‐ANIE1335%3e3.0.CO;2‐A
  Reetz, M. T., Becker, M. H., Kuhling, K. M., & Holzwarth, A. (1998). Time‐resolved IR‐thermographic detection and screening of enantioselectivity in catalytic reactions. Angewandte Chemie (International ed. in English), 37, 2647–2650. doi: 10.1002/(SICI)1521‐3773(19981016)37:19%3c2647::AID‐ANIE2647%3e3.0.CO;2‐I
  Reetz, M. T., Becker, M. H., Liebl, M., & Fürstner, A. (2000). IR‐thermographic screening of thermoneutral or endothermic transformations: The ring‐closing olefin metathesis reaction. Angewandte Chemie (International ed. in English), 39, 1236–1239. doi: 10.1002/(SICI)1521‐3773(20000403)39:7%3c1236::AID‐ANIE1236%3e3.0.CO;2‐J
  Robbins, D. W., & Hartwig, J. F. (2011). A simple, multidimensional approach to high‐throughput discovery of catalytic reactions. Science, 333, 1423–1427. doi: 10.1126/science.1207922
  Schaus, S. E., Brandes, B. D., Larrow, J. F., Tokunaga, M., Hansen, K. B., Gould, A. E., … Jacobsen, E. N. (2002). Highly selective hydrolytic kinetic resolution of terminal epoxides catalyzed by chiral (salen)Co(III) complexes. Practical synthesis of enantioenriched terminal epoxides and 1,2‐diols. Journal of the American Chemical Society, 124, 1307–1315. doi: 10.1021/ja016737l
  Shabbir, S. H., Joyce, L. A., da Cruz, G. M., Lynch, V. M., Sorey, S., & Anslyn, E. V. (2009). Pattern‐based recognition for the rapid determination of identity, concentration, and enantiomeric excess of subtly different threo‐diols. Journal of the American Chemical Society, 131, 13125–13131. doi: 10.1021/ja904545d
  Sprout, C. M., Richmond, M. L., & Seto, C. T. (2005). A positional scanning approach to the discovery of dipeptide‐based catalysts for the enantioselective addition of vinylzinc reagents to aldehydes. The Journal of Organic Chemistry, 70, 7408–7417. doi: 10.1021/jo051342w
  Stambuli, J. P., & Hartwig, J. F. (2003). Recent advances in the discovery of organometallic catalysts using high‐throughput screening assays. Current Opinion in Chemical Biology, 7, 420–426. doi: 10.1016/S1367‐5931(03)00056‐5
  Taran, F., Gauchet, C., Mohar, B., Meunier, S., Valleix, A., Renard, P. Y., … Mioskowski, C. (2002). High‐throughput screening of enantioselective catalysts by immunoassay. Angewandte Chemie (International ed. in English), 41, 124–127. doi: 10.1002/1521‐3773(20020104)41:1%3c124::AID‐ANIE124%3e3.0.CO;2‐R
  Taylor, S. J., & Morken, J. P. (1998). Thermographic selection of effective catalysts from an encoded polymer‐bound library. Science, 280, 267–270. doi: 10.1126/science.280.5361.267
  Treece, J. L., Goodell, J. R., Vander Velde, D., Porco, J. A., Jr., & Aube, J. (2010). Reaction discovery using microfluidic‐based multidimensional screening of polycyclic iminium ethers. The Journal of Organic Chemistry, 75, 2028–2038. doi: 10.1021/jo100087h
  Trost, B. M., Bunt, R. C., Lemoine, R. C., & Calkins, T. L. (2000). Dynamic kinetic asymmetric transformation of diene monoepoxides: A practical asymmetric synthesis of vinylglycinol, vigabatrin, and ethambutol. Journal of the American Chemical Society, 122, 5968–5976. doi: 10.1021/ja000547d
  Yoon, T. P., & Jacobsen, E. N. (2003). Privileged chiral catalysts. Science, 299, 1691–1693. doi: 10.1126/science.1083622
GO TO THE FULL PROTOCOL:
PDF or HTML at Wiley Online Library