Stereodivergent Catalysis Contents
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Enantiotopicity, Diastereotopicity
Stereochemistry and stereocontrolled synthesis (OC 8) A lecture from Prof. Paul Knochel, Ludwig-Maximilians-Universität München WS 2015-16 1 Wichtig! • Prüfung Stereochemistry 02. Februar 2016 8:00 – 10:00 Willstätter-HS • Nachholklausur Stereochemistry 5. April 2016 9:00 – 11:00 Willstätter-HS 2 Problem set part I 3 Problem set part II 4 Problem set part III 5 Recommended Literature • E. Juaristi, Stereochemistry and Conformational Analysis, Wiley, 1991. • E. Eliel, Stereochemistry of Organic Compounds, Wiley, 1994. • A. Koskinen, Asymmetric Synthesis of Natural Products, Wiley, 1993. • R. Noyori, Asymmetric Catalysis, Wiley, 1994. • F. A. Carey, R. J. Sundberg, Advanced Organic Chemistry, 5th Edition, Springer, 2007. • A. N. Collins, G. N. Sheldrake, J. Crosby, Chirality in Industrie, Vol. I and II, Wiley, 1995 and 1997. • G.Q. Lin, Y.-M. Li, A.S.C. Chan, Asymmetric Synthesis, 2001, ISBN 0-471-40027-0. • P. Deslongchamps, Stereoelectronic Effects in Organic Chemistry, Pergamon, 1983. • M. Nogradi, Stereoselective Synthesis, VCH, 1995. • E. Winterfeldt, Stereoselective Synthese, Vieweg, 1988. • R. Mahrwald (Ed.), Modern Aldol Reactions, Vol. I and II, Wiley, 2004. • C. Wolf, Dynamic Stereochemistry of Chiral Compounds, RSC Publishing, 2008. • A. Berkessel, H. Gröger, Asymmetric Organocatalysis, Wiley-VCH, 2005. • J. Christoffers, A. Baro (Eds.), Quaternary Stereocenters, Wiley-VCH, 2005. • Catalytic Asymmetric Synthesis, I. Oshima (Ed.), Wiley, 2010. 6 Recent advances of asymmetric catalysis 7 Asymmetric Hydrogenation of Heterocyclic Compounds 8 R. Kuwano, N. Kameyama, R. Ikeda, J. Am. Chem. Soc. 2011, 133, 7312-7315. Camphor-Derived Organocatalytic Synthesis of Chromanones 9 Z.-Q. Rong, Y. Li, G.-Q. Yang, S.-L. You, Synlett 2011, 1033-1037. -
Alcohols Combined 1405
ALCOHOLS COMBINED 1405 Formulas: Table 1 MW: Table 1 CAS: Table 2 RTECS: Table 2 METHOD: 1405, Issue 1 EVALUATION: PARTIAL Issue 1: 15 March 2003 OSHA : Table 2 PROPERTIES: Table 1 NIOSH: Table 2 ACGIH: Table 2 COMPOUNDS: (1) n-butyl alcohol (4) n-propyl alcohol (7) cyclohexanol (2) sec-butyl alcohol (5) allyl alcohol (8) isoamyl alcohol (3) isobutyl alcohol (6) diacetone alcohol (9) methyl isobutyl carbinol SYNONYMS: See Table 3. SAMPLING MEASUREMENT SAMPLER: SOLID SORBENT TUBE TECHNIQUE: GAS CHROMATOGRAPHY, FID (Coconut shell charcoal, 100 mg/50 mg) ANALYTE: Compounds above FLOW RATE: 0.01 to 0.2 L/min DESORPTION: 1 mL 5% 2-propanol in CS2 Compounds: (1-3 ) (4-9) VOL-MIN: 2 L 1 L INJECTION -MAX: 10 L 10 L VOLUME: 1 µL SHIPMENT: Routine TEMPERATURE -INJECTION: 220 °C SAMPLE -DETECTOR: 250 - 300 °C STABILITY: See Evaluation of Method. -COLUMN: 35 °C (7 minutes), to 60 °C at 5 °C/minute, hold 5 minutes, up to BLANKS: 2 to 10 field blanks per set 120 °C at 10 °C /minute, hold 3 minutes. CARRIER GAS: He, 4 mL/min ACCURACY COLUMN: Capillary, fused silica, 30 m x 0.32-mm RANGE STUDIED: Not studied [1, 2]. ID; 0.5 µm film polyethylene glycol, DB- wax or equivalent BIAS: Not determined CALIBRATION: Solutions of analyte in eluent (internal OVERALL standard optional) PRECISION (Ö ): Not determined rT RANGE: See EVALUATION OF METHOD. ACCURACY: Not determined ESTIMATED LOD: 1 µg each analyte per sample PRECISION: See EVALUATION OF METHOD. APPLICABILITY: This method may be used to determine two or more of the specified analytes simultaneously. -
Enantiotopic Discrimination in the NMR Spectrum of Prochiral Solutes in Chiral Liquid Crystals
Chemical Society Reviews Enantiotopic Discrimination in the NMR Spectrum of Prochiral Solutes in Chiral Liquid Crystals Journal: Chemical Society Reviews Manuscript ID: CS-REV-07-2014-000260 Article Type: Review Article Date Submitted by the Author: 29-Jul-2014 Complete List of Authors: Lesot, Phillippe; Universite Paris Sud (Paris XI), LRMN, ICMMO, UMR 8182 Aroulanda, Christie; Universite Paris Sud (Paris XI), LRMN, ICMMO, UMR 8182 Zimmermann, Herbert; Abteilung Biophysik, Max-Planck-Institut für Medizinische Forschung, Luz, Zeev; Weizmann Institute of Science, Department of Chemical Physics Page 1 of 117 Chemical Society Reviews Chem. Soc. Rev. (2014) - 1 - Enantiotopic Discrimination in the NMR Spectrum of Prochiral Solutes in Chiral Liquid Crystals Philippe Lesot* ,a , Christie Aroulanda a, Herbert Zimmermann b and Zeev Luz c a Laboratoire de RMN en Milieu Orienté CNRS UMR 8182, ICMMO, Bât. 410, Université de Paris-Sud, 91405 Orsay cedex, France. bAbteilung Biophysik, Max-Planck-Institut für Medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany. c Weizmann Institute of Science, Department of Chemical Physics, Rehovot 76100, Israel. Corresponding author : Philippe Lesot: [email protected] Keywords : Prochirality, Enantiotopic sites, NMR, Chiral Liquid Crystals, Dynamics. Type of article : (comprehensive) review Chemical Society Reviews Page 2 of 117 Chem. Soc. Rev. (2014) - 2 - Abstract The splitting of signals in the NMR spectra originating from enantiotopic sites in prochiral molecules when dissolved in chiral solvents is referred to as spectral enantiotopic discrimination. The phenomenon is particularly noticeable in chiral liquid crystals (CLC) due to the combined effect of the anisotropic magnetic interactions and the ordering of the solute in the mesophase. -
The Control of Stereochemistry by the Pentafluorosulfanyl Group
Organic & Biomolecular Chemistry View Article Online PAPER View Journal | View Issue The control of stereochemistry by the pentafluorosulfanyl group† Cite this: Org. Biomol. Chem., 2018, 16, 3151 Paul R. Savoie, Cortney N. von Hahmann, Alexander Penger, Zheng Wei and John T. Welch * The influence of pentafluorosulfanylation on biological activity has been revealed in numerous compara- tive studies of biologically active compounds, but considerably less is known about the influence of pen- tafluorosulfanylation on reactivity. Among the distinctive properties of the pentafluorosulfanyl group is the profound dipole moment that results from introduction of this substituent. It has been shown that dipolar Received 20th December 2017, effects coupled with the steric demand of the SF5 group may be employed to influence the stereo- Accepted 3rd April 2018 chemistry of reactions, especially those processes with significant charge separation in the transition DOI: 10.1039/c7ob03146g state. The Staudinger ketene-imine cycloaddition reaction is an ideal platform for investigation of dipolar rsc.li/obc control of diastereoselectivity by the pentafluorosulfanyl group. Introduction ation into a hydrocarbon chain, the restricted rotation about the carbon–sulfur bond that results from interactions with Numerous pentafluorosulfanyl(SF5)-containing organic nearby methylene groups, can lead to localized conformational – compounds1 10 have been prepared that have potential utility rigidity of the alkyl chain.21,22 in drug discovery, agrochemical synthesis and materials -
Multicatalytic, Asymmetric Michael/Stetter Reaction Of
Multicatalytic, asymmetric Michael/Stetter reaction SPECIAL FEATURE of salicylaldehydes and activated alkynes Claire M. Filloux, Stephen P. Lathrop, and Tomislav Rovis1 Department of Chemistry, Colorado State University, Fort Collins, CO 80523 Edited by David W. C. MacMillan, Princeton University, Princeton, NJ, and accepted by the Editorial Board May 30, 2010 (received for review March 22, 2010) We report the development of a multicatalytic, one-pot, asymmetric Ar Ar Michael/Stetter reaction between salicylaldehydes and electron- N H deficient alkynes. The cascade proceeds via amine-mediated OO 3 OTMS (20 mol %) Me HO Me Michael addition followed by an N-heterocyclic carbene-promoted Me Me 1 Ar = 3,5-(CF3)2C6H3 O intramolecular Stetter reaction. A variety of salicylaldehydes, dou- + O O BF4 N bly activated alkynes, and terminal, electrophilic allenes participate 2 Me 5 Me in a one-step or two-step protocol to give a variety of benzofura- NNC F 4a 6 5 One-Pot Two - Po t none products in moderate to good yields and good to excellent (10 mol %) 93% yield 46% yield NaOAc (10 mol %) 85:15:<1:<1 dr 5:1 dr enantioselectivities. The origin of enantioselectivity in the reaction 86% ee 58% ee CHCl3, 23 C is also explored; E∕Z geometry of the reaction intermediate as well as the presence of catalytic amounts of catechol additive are O found to influence reaction enantioselectivity. O Me * O Me ∣ ∣ catalysis organic synthesis tandem catalysis Me 6 ascade catalysis has garnered significant recent attention Scheme 1. Multicatalytic Michael/Benzoin cascade. Cfrom the synthetic community as a means to swiftly assemble CHEMISTRY complex molecules from simple starting materials with minimal benzofuranones. -
Chapter 8. Chiral Catalysts José M
Chapter 8. Chiral Catalysts José M. Fraile, José I. García, José A. Mayoral 1. The Origin of Enantioselectivity in Catalytic Processes: the Nanoscale of Enantioselective Catalysis. Enantiomerically pure compounds are extremely important in fields such as medicine and pharmacy, nutrition, or materials with optical properties. Among the different methods to obtain enantiomerically pure compounds, asymmetric catalysis1 is probably the most interesting and challenging, in fact one single molecule of chiral catalyst can transfer its chiral information to thousands or even millions of new chiral molecules. Enantioselective reactions are the result of the competition between different possible diastereomeric reaction pathways, through diastereomeric transition states, when the prochiral substrate complexed to the chiral catalyst reacts with the corresponding reagent. The efficiency of the chirality transfer, measured as enantiomeric excess [% ee = (R−S)/(R+S) × 100], depends on electronic and steric factors in a very subtle form. A simple calculation shows that differences in energy of only 2 kcal/mol between these transition states are enough to obtain more than 90% ee, and small changes in any of the participants in the catalytic process can modify significantly this difference in energy. Those modifications may occur in the near environment of the catalytic centre, at less than 1 nm scale, but also at longer distances in the catalyst, substrate, reagent, solvent, or support in the case of immobilized catalysts. This is the reason because asymmetric -
(12) Patent Application Publication (10) Pub. No.: US 2012/0321727 A1 Windschauer Et Al
US 20120321727A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2012/0321727 A1 Windschauer et al. (43) Pub. Date: Dec. 20, 2012 (54) TASTE MASKING COMPOSITIONS AND A636/54 (2006.01) EDIBLE FORMS THEREOF A6II 3/40 (2006.01) A6II 3L/225 (2006.01) (75) Inventors: Robert J. Windschauer, Largo, FL A6IP 5/00 (2006.01) (US); Teresa T. Virgallito, A2.3L. I./22 (2006.01) Beavercreek, OH (US) A2.3L I/0562 (2006.01) A2.3L I/053 (2006.01) (73) Assignee: ACME SPECIALTY A2.3L I/054 (2006.01) PRODUCTS, LLC, Tampa, FL A2.3L I/0524 (2006.01) (US) A2.3L I/0522 (2006.01) A2.3L I/0532 (2006.01) (21) Appl. No.: 13/455,520 A2.3L I/0534 (2006.01) A2.3L I/0526 (2006.01) (22) Filed: Apr. 25, 2012 A23G 3/42 (2006.01) O O A63L/453 (2006.01) Related U.S. Application Data (52) U.S. Cl. ......... 424/737; 514/326; 424/769; 424/760; (60) Provisional application No. 61/480,102, filed on Apr. 424/754; 424/755; 424/756; 514/718; 514/627; 28, 2011. 424/739; 514/425; 514/548; 426/650: 426/573; 426/576; 426/577; 426/578; 426/575 Publication Classification (57) ABSTRACT (51) Int. Cl. A23G 3/36 (2006.01) Disclosed are edible formulations, for example, edible films A6 IK 36/28 (2006.01) and gummi confectioneries, that mask the taste of semen. The A6 IK 36/758 (2006.01) films and confectioneries include a composition that upon A6 IK 36/8 (2006.01) activation in the oral cavity provides a lasting taste masking A6 IK 36/8962 (2006.01) effect that endures for up to 20 minutes. -
Preparation of N Butyl Bromide Lab Report
Preparation Of N Butyl Bromide Lab Report Hoiden Wendell ingurgitate some Ellis and imperilling his odyssey so less! Embowed Preston usually flow some yeanling or readapts injudiciously. Paco is punitory and fossilizing regeneratively as miscible Phillipe inosculated intently and erased halfway. In reactivity of asking others to perform this helps facilitate the bromide lab report is reduced extensor muscle necrosis was performed Exp 23 Synthesis of n-Butyl Bromide and t-Pentyl 99-107. Organic Syntheses Procedure. Do this page is used a feasible to lighten the preparation of configuration at infinite dilution have to a sterically hindered aromatic stabilization and relative reactivity. Williamson ether synthesis video Khan Academy. The energy barrier is a haloalkane, is used a test tube. The total stereoselective synthesis of cis insect sex attractants. Experiment you will raid a Grignard reagent and react it incorporate an ester to near a tertiary alcohol Specifically in this reaction you also prepare phenyl magnesium bromide from. The boiling point of n-butyl bromide is 100 oC while expression of n-butyl chloride is 77. Substitution-lab Metabolomics. Some properties in this technique with an iron in after each reaction is added tantalum or primary halides. The records will be needed to generate lab reports at some point remains the. In today's experiment you will carry out the first gear of the barbiturate synthesis In reactions involving. Reactions of Tertiary Phosphites with Alkyl Iodides in Acetonitrile. Experiment will just the SN reactivity of alkyl halides To some worry this experiment is trap to the. Discussed here react more rapidly in solutions prepared from these solvents. -
Equilibrium Structures and Vibrational Assignments for Isoamyl Alcohol and Tert-Amyl Alcohol: a Density Functional Study
Equilibrium Structures and Vibrational Assignments for Isoamyl Alcohol and tert-Amyl Alcohol: A Density Functional Study Wolfgang Forner¨ and Hassan M. Badawi Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia Reprint requests to Wolfgang Forner.¨ E-mail: [email protected] Z. Naturforsch. 2013, 68b, 841 – 851 / DOI: 10.5560/ZNB.2013-3003 Received February 9, 2013 We have calculated the vibrational spectra of isoamyl alcohol and of tert-amyl alcohol using Den- sity Functional Theory (DFT) with the Becke-3 Lee Yang Parr (B3LYP) functional and a 6-311+G** atomic basis set. The energies of the conformers were also calculated with ab initio Perturbation Theory of second (MP2) and fourth order restricted to single, double and quadruple excitations (MP4 SDQ) with the same basis set. We found rather complicated equilibria of four conformations in each case, counting only those with appreciable abundancies. PED data were compared with GAUSSVIEW animations. The calculated wavenumbers agree rather well with the experimental ones when the gauche-trans conformer is assumed as the most important one for isoamyl alcohol, and the gauche- gauche one for tert-amyl alcohol. However, some of the experimental bands had to be assigned also to other conformers, indicating their presence in the equilibrium mixture. Due to sterical reasons both the CO and the OH bonds appear to be weaker in the tertiary alcohol, considering the wavenumbers of the CO and OH bond stretching vibrations. The bond lengths point into the same direction, however, the OH bond in the tertiary alcohol is only slightly longer than that in the primary alcohol. -
Dulaneyspr15.Pdf (409.1Kb)
Adventures in Organophosphorus Chemistry James W. Dulaney, III (Faculty Mentor: David E. Lewis) Department of Chemistry, University of Wisconsin-Eau Claire, Eau Claire, WI 54702-4004 Background Challenges with the Mitsunobu reaction What is required in a replacement to make the reaction Azodicarboxylates, an important component of the re- “green”? Organophosphorus compounds have been an increasingly important part of organic synthesis since the discovery action, are very hazardous: of the Arbuzov rearrangement in 1905. In the century that followed this discovery, the applications of phosphorus- O Green? based reagents in synthesis has grown to incorporate the Wittig and Horner-Wadsworth-Emmons reactions for OEt • They are highly explosive (especially diethyl azodi- N alkene formation, as well as the Mitsunobu inversion reaction, which is used to convert alcohols to a wide range carboxylate). N Green reactions are run under more environmentally sustainable conditions with a view to of products with inversion of configuration. O minimizing environmental impact: • They are highly toxic (especially diethyl azodicar- OEt boxylate). diethyl azodicarboxylate • They are highly regulated. (DEAD) • Wherever possible, renewable sources are used • Wherever possible, hazardous materials are eliminated completely or replaced by The Wittig reaction Ph Ph Ph BuLi Ph less hazardous materials P R P R Regulations have been put into place by the DOT that O Ph Ph O-i-Pr • Wherever possibler, catalytic reactions are used Reaction between an ylide and an aldehyde or ketone to give an alkene. make azodicarboxylic esters even more difficult to ob- N • Hazardous waste is minimized wherever possible (e.g. organic solvents can be re- Reaction gives mainly the Z isomer with aldehydes O tain and use. -
Working with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training in experimental organic chemistry. All hazardous materials should be handled using the standard procedures for work with chemicals described in references such as "Prudent Practices in the Laboratory" (The National Academies Press, Washington, D.C., 2011; the full text can be accessed free of charge at http://www.nap.edu/catalog.php?record_id=12654). All chemical waste should be disposed of in accordance with local regulations. For general guidelines for the management of chemical waste, see Chapter 8 of Prudent Practices. In some articles in Organic Syntheses, chemical-specific hazards are highlighted in red “Caution Notes” within a procedure. It is important to recognize that the absence of a caution note does not imply that no significant hazards are associated with the chemicals involved in that procedure. Prior to performing a reaction, a thorough risk assessment should be carried out that includes a review of the potential hazards associated with each chemical and experimental operation on the scale that is planned for the procedure. Guidelines for carrying out a risk assessment and for analyzing the hazards associated with chemicals can be found in Chapter 4 of Prudent Practices. The procedures described in Organic Syntheses are provided as published and are conducted at one's own risk. Organic Syntheses, Inc., its Editors, and its Board of Directors do not warrant or guarantee the safety of individuals using these procedures and hereby disclaim any liability for any injuries or damages claimed to have resulted from or related in any way to the procedures herein. -
Third Supplement, FCC 11 Index / All-Trans-Lycopene / I-1
Third Supplement, FCC 11 Index / All-trans-Lycopene / I-1 Index Titles of monographs are shown in the boldface type. A 2-Acetylpyridine, 20 Alcohol, 80%, 1524 3-Acetylpyridine, 21 Alcohol, 90%, 1524 Abbreviations, 6, 1726, 1776, 1826 2-Acetylpyrrole, 21 Alcohol, Absolute, 1524 Absolute Alcohol (Reagent), 5, 1725, 2-Acetyl Thiazole, 18 Alcohol, Aldehyde-Free, 1524 1775, 1825 Acetyl Valeryl, 562 Alcohol C-6, 579 Acacia, 556 Acetyl Value, 1400 Alcohol C-8, 863 ªAccuracyº, Defined, 1538 Achilleic Acid, 24 Alcohol C-9, 854 Acesulfame K, 9 Acid (Reagent), 5, 1725, 1775, 1825 Alcohol C-10, 362 Acesulfame Potassium, 9 Acid-Hydrolyzed Milk Protein, 22 Alcohol C-11, 1231 Acetal, 10 Acid-Hydrolyzed Proteins, 22 Alcohol C-12, 681 Acetaldehyde, 10 Acid Calcium Phosphate, 219, 1838 Alcohol C-16, 569 Acetaldehyde Diethyl Acetal, 10 Acid Hydrolysates of Proteins, 22 Alcohol Content of Ethyl Oxyhydrate Acetaldehyde Test Paper, 1535 Acidic Sodium Aluminum Phosphate, Flavor Chemicals (Other than Acetals (Essential Oils and Flavors), 1065 Essential Oils), 1437 1395 Acidified Sodium Chlorite Alcohol, Diluted, 1524 Acetanisole, 11 Solutions, 23 Alcoholic Potassium Hydroxide TS, Acetate C-10, 361 Acidity Determination by Iodometric 1524 Acetate Identification Test, 1321 Method, 1437 Alcoholometric Table, 1644 Aceteugenol, 464 Acid Magnesium Phosphate, 730 Aldehyde C-6, 571 Acetic Acid Furfurylester, 504 Acid Number (Rosins and Related Aldehyde C-7, 561 Acetic Acid, Glacial, 12 Substances), 1418 Aldehyde C-8, 857 Acetic Acid TS, Diluted, 1524 Acid Phosphatase