Organic Reaction Mechanisms Series
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Part I Principles of Enzyme Catalysis
j1 Part I Principles of Enzyme Catalysis Enzyme Catalysis in Organic Synthesis, Third Edition. Edited by Karlheinz Drauz, Harald Groger,€ and Oliver May. Ó 2012 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2012 by Wiley-VCH Verlag GmbH & Co. KGaA. j3 1 Introduction – Principles and Historical Landmarks of Enzyme Catalysis in Organic Synthesis Harald Gr€oger and Yasuhisa Asano 1.1 General Remarks Enzyme catalysis in organic synthesis – behind this term stands a technology that today is widely recognized as a first choice opportunity in the preparation of a wide range of chemical compounds. Notably, this is true not only for academic syntheses but also for industrial-scale applications [1]. For numerous molecules the synthetic routes based on enzyme catalysis have turned out to be competitive (and often superior!) compared with classic chemicalaswellaschemocatalyticsynthetic approaches. Thus, enzymatic catalysis is increasingly recognized by organic chemists in both academia and industry as an attractive synthetic tool besides the traditional organic disciplines such as classic synthesis, metal catalysis, and organocatalysis [2]. By means of enzymes a broad range of transformations relevant in organic chemistry can be catalyzed, including, for example, redox reactions, carbon–carbon bond forming reactions, and hydrolytic reactions. Nonetheless, for a long time enzyme catalysis was not realized as a first choice option in organic synthesis. Organic chemists did not use enzymes as catalysts for their envisioned syntheses because of observed (or assumed) disadvantages such as narrow substrate range, limited stability of enzymes under organic reaction conditions, low efficiency when using wild-type strains, and diluted substrate and product solutions, thus leading to non-satisfactory volumetric productivities. -
Recyclable Catalysts for Alkyne Functionalization
molecules Review Recyclable Catalysts for Alkyne Functionalization Leslie Trigoura 1,2 , Yalan Xing 1,* and Bhanu P. S. Chauhan 2,* 1 Department of Chemistry, William Paterson University of New Jersey, 300 Pompton Road, Wayne, NJ 07470, USA; [email protected] 2 Engineered Nanomaterials Laboratory, Department of Chemistry, William Paterson University of New Jersey, 300 Pompton Road, Wayne, NJ 07470, USA * Correspondence: [email protected] (Y.X.); [email protected] (B.P.S.C.); Tel.: +1-973-720-2470 (B.P.S.C.) Abstract: In this review, we present an assessment of recent advances in alkyne functionalization reactions, classified according to different classes of recyclable catalysts. In this work, we have in- corporated and reviewed the activity and selectivity of recyclable catalytic systems such as polysiloxane- encapsulated novel metal nanoparticle-based catalysts, silica–copper-supported nanocatalysts, graphitic carbon-supported nanocatalysts, metal organic framework (MOF) catalysts, porous organic frame- work (POP) catalysts, bio-material-supported catalysts, and metal/solvent free recyclable catalysts. In addition, several alkyne functionalization reactions have been elucidated to demonstrate the success and efficiency of recyclable catalysts. In addition, this review also provides the fundamental knowl- edge required for utilization of green catalysts, which can combine the advantageous features of both homogeneous (catalyst modulation) and heterogeneous (catalyst recycling) catalysis. Keywords: green catalysts; nanosystems; nanoscale catalysts; catalyst modulation; alkyne functional- ization; coupling reactions Citation: Trigoura, L.; Xing, Y.; 1. Introduction Chauhan, B.P.S. Recyclable Catalysts for Alkyne Functionalization. Alkyne functionalization methods constitute one of the most relevant topics in organic Molecules 2021, 26, 3525. https:// synthesis and has resulted in numerous advancements over several years. -
Organometallic Chemistry BASIC PRINCIPLES, APPLICATIONS, and a FEW CASE STUDIES
Safety Moment TYLER LAB GROUP MEETING 1 Safety Moment TYLER LAB GROUP MEETING 2 Metal Hydrides: Benchtop vs. Box Hydride = :H- Hydrides are powerful Lewis bases and reducing agent ◦ Exothermically form H2 (this should scare you) ◦ Heating leads to faster reactivity ◦ H evolution leads to rapid increase in pressure2 ◦ Uncontrolled reactions easily cause runaway exotherm, class D fire, explosion, and death/unemployment LiAlH is the #1 chemical cause of fatality in chemical4 industry 3 Metal Hydrides: “I want to commit the murder I was imprisoned for†.” LiAlH4 ◦ Insanely irritating (serious safety hazard) ◦ Extremely moisture sensitive (don’t leave out for >2 minutes) ◦ Ethereal mixtures are pyrophoric! DiBuAl-H ◦ Pyrophoric – it will explode upon exposure to oxygen NaEt3BH ◦ Pyrophoric in solution LiH and NaH ◦ Can be handled on the benchtop (not >2 minutes) ◦ Parrafin oil dispersions much safer KH ◦ Pyrophoric if not in a dispersion ◦ Handle with extreme care! † Sirius Black, Harry Potter and the Prisoner of Azkaban 4 Metal Hydrides: “I want to commit the murder I was imprisoned for†.” CaH2 ◦ Very safe to handle on the benchtop Pt-H, Pd-H, Ni-H ◦ All very pyrophoric NaBH4 ◦ Very safe in general Other hydrides ◦ Treat as pyrophoric ◦ Transition metal hydrides vary in hydridic strength ◦ General rule of thumb: if it does hydrogenations, it is probably pyrophoric ◦ If they’re in organics of any kind, they are probably pyrophoric † Sirius Black, Harry Potter and the Prisoner of Azkaban 5 Organometallic Chemistry BASIC PRINCIPLES, APPLICATIONS, -
Enantioselective Synthesis of (-)-Vallesine: Late- Stage C17-Oxidation Via Complex Indole Boronation
Enantioselective synthesis of (-)-vallesine: late- stage C17-oxidation via complex indole boronation The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Antropow, Alyssa H., et al., "Enantioselective synthesis of (-)-vallesine: late-stage C17-oxidation via complex indole boronation." Organic Letters 20, 12 (2018): p. 3647-50 doi 10.1021/ acs.orglett.8b01428 ©2018 Author(s) As Published 10.1021/acs.orglett.8b01428 Publisher American Chemical Society (ACS) Version Author's final manuscript Citable link https://hdl.handle.net/1721.1/125882 Terms of Use Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. HHS Public Access Author manuscript Author ManuscriptAuthor Manuscript Author Org Lett Manuscript Author . Author manuscript; Manuscript Author available in PMC 2019 June 15. Published in final edited form as: Org Lett. 2018 June 15; 20(12): 3647–3650. doi:10.1021/acs.orglett.8b01428. Enantioselective Synthesis of (−)-Vallesine: Late-stage C17- Oxidation via Complex Indole Boronation Alyssa H. Antropow, Nicholas R. Garcia, Kolby L. White, and Mohammad Movassaghi* Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA Abstract The first enantioselective total synthesis of (−)-vallesine via a strategy that features a late-stage regioselective C17-oxidation, followed by a highly stereoselective transannular cyclization is reported. The versatility of this approach is highlighted by divergent synthesis of the archetypal alkaloid of this family, (+)-aspidospermidine, and an A-ring oxygenated derivative (+)- deacetylaspidospermine, the precursor to (−)-vallesine, from a common intermediate. -
Electrochemistry and Photoredox Catalysis: a Comparative Evaluation in Organic Synthesis
molecules Review Electrochemistry and Photoredox Catalysis: A Comparative Evaluation in Organic Synthesis Rik H. Verschueren and Wim M. De Borggraeve * Department of Chemistry, Molecular Design and Synthesis, KU Leuven, Celestijnenlaan 200F, box 2404, 3001 Leuven, Belgium; [email protected] * Correspondence: [email protected]; Tel.: +32-16-32-7693 Received: 30 March 2019; Accepted: 23 May 2019; Published: 5 June 2019 Abstract: This review provides an overview of synthetic transformations that have been performed by both electro- and photoredox catalysis. Both toolboxes are evaluated and compared in their ability to enable said transformations. Analogies and distinctions are formulated to obtain a better understanding in both research areas. This knowledge can be used to conceptualize new methodological strategies for either of both approaches starting from the other. It was attempted to extract key components that can be used as guidelines to refine, complement and innovate these two disciplines of organic synthesis. Keywords: electrosynthesis; electrocatalysis; photocatalysis; photochemistry; electron transfer; redox catalysis; radical chemistry; organic synthesis; green chemistry 1. Introduction Both electrochemistry as well as photoredox catalysis have gone through a recent renaissance, bringing forth a whole range of both improved and new transformations previously thought impossible. In their growth, inspiration was found in older established radical chemistry, as well as from cross-pollination between the two toolboxes. In scientific discussion, photoredox catalysis and electrochemistry are often mentioned alongside each other. Nonetheless, no review has attempted a comparative evaluation of both fields in organic synthesis. Both research areas use electrons as reagents to generate open-shell radical intermediates. Because of the similar modes of action, many transformations have been translated from electrochemical to photoredox methodology and vice versa. -
Total Synthesis of Aspeverin and Penicimutamide a Part Ii
PART I: TOTAL SYNTHESIS OF ASPEVERIN AND PENICIMUTAMIDE A PART II: TOTAL CHEMICAL SYNTHESIS OF ALL-L AND ALL-D KRAS(G12V) AND THE FURTHER EXPLORATION OF ISONITRILE- MEDIATED PEPTIDE LIGATIONS A Dissertation Presented to the Faculty of the Weill Cornell Graduate School of Medical Sciences in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy by Adam M. Levinson January 2017 © Adam M. Levinson 2016 PART I: TOTAL SYNTHESIS OF ASPEVERIN AND PENICIMUTAMIDE A PART II: TOTAL CHEMICAL SYNTHESIS AND FOLDING OF ALL-L AND ALL-D KRAS(G12V) AND THE FURTHER EXPLORATION OF ISONITRILE- MEDIATED PEPTIDE LIGATIONS Adam M. Levinson Cornell University 2016 Part I: Fungi serve as a rich source of prenylated indole alkaloids, which exhibit important biological activities including antiproliferative, antibiotic, and antihelminthic properties. Their promise as therapeutics, coupled with their diverse and complex molecular architectures, have made prenylated indole alkaloids popular targets for synthetic chemists in order to probe their activities and develop new synthetic methods. Herein, we describe the first total synthesis of aspeverin, a unique bridged carbamate-containing prenylated indole alkaloid isolated from Aspergillus versicolor. We also describe the synthesis of a closely related congener, penicimutamide A, isolated from a mutant strain of Penicillium purpurogenum. These molecules belong to a recently described subclass of prenylated indoles thought to be degradation products of parent bicyclo[2.2.2]diazaoctane congeners. In this research, we showcase a highly diastereoselective Diels−Alder cycloaddition, followed by an electrophilic Rawal arylation – reductive indolization to forge the pentacyclic scaffold of these natural products. A novel sequence for installation of a geminal dimethyl group was also developed. -
6.-Organic-Chemistry-I-Edexcel.Pdf
6: Organic Chemistry I 6A. Introduction to Organic Chemistry Basic definitions Hydrocarbon is a compound consisting of hydrogen and carbon only to know Saturated: Contain single carbon-carbon bonds only Unsaturated : Contains a C=C double bond Molecular formula: The formula which shows the actual number of each type of atom Empirical formula: shows the simplest whole number ratio of atoms of each element in the compound General formula: algebraic formula for a homologous series e.g. CnH2n Structural formula shows the minimal detail that shows the arrangement of atoms in a molecule, eg for butane: CH3CH2CH2CH3 or CH3(CH2)2CH3, Displayed formula: show all the covalent bonds present in a molecule Drawing Displayed formulae Remember that the shape around the carbon atom in saturated hydrocarbons is H H H H When drawing organic tetrahedral and the bond angle is 109.5o H C C C C H compounds add the hydrogen atoms so that H H H H H H C H each carbon has 4 bonds H C C H H H H Skeletal formula shows the simplified organic formula, shown by removing hydrogen atoms from alkyl chains, leaving just a carbon skeleton and associated functional Groups. OH But-2-ene Butan-1-ol 2-methylbutane cyclohexane cyclohexene N Goalby chemrevise.org 1 Homologous series are families of organic compounds with the same functional group and same general formula. •They show a gradual change in physical properties (e.g. boiling point). • Each member differs by CH2 from the last. • same chemical properties. Functional group is an atom or group of atoms which when present -
(12) Patent Application Publication (10) Pub. No.: US 2017/0056513 A1 Hedrick Et Al
US 2017.0056513A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2017/0056513 A1 Hedrick et al. (43) Pub. Date: Mar. 2, 2017 (54) THERAPEUTIC COMPOSITIONS Publication Classification COMPRISING N-ALKYL-HYDROXY POLYMERS (51) Int. Cl. A6II 47/48 (2006.01) (71) Applicant: INTERNATIONAL BUSINESS A6IR 48/00 (2006.01) MACHINES CORPORATION, A63L/73 (2006.01) Armonk, NY (US) (52) U.S. Cl. CPC ...... A61K 47/48192 (2013.01); A61 K3I/713 (72) Inventors: James Hedrick, San Jose, CA (US); (2013.01); A61K 48/00 (2013.01) Dylan BODAY, San Jose, CA (US); Jeannette GARCIA, San Jose, CA (US); Rudy WOJTECKI, San Jose, (57) ABSTRACT CA (US); Yi Yan YANG, The Nanos (SG); Chuan Yang. The Nanos (SG) The disclosure describes methods and therapeutic composi tions comprising polymers modified with N-alkyl-hydroxy (21) Appl. No.: 14/836,614 groups comprising one or more carbon atoms. The compo sitions are useful for gene delivery, and exhibit broad (22) Filed: Aug. 26, 2015 spectrum antiviral activity and low toxicity in vitro. Patent Application Publication Mar. 2, 2017 Sheet 1 of 2 US 2017/0056513 A1 10. 0.15 eq. Paraformaldehyde 2 9. 8 s 5 4. c 3. 2 s g & S As ss N. Concentration (ng) Figure 1A 1. 0.30 eg. Paraformaidehyde 9 - 8 f S 5 a 30 2 . xx 22---- 2 S. $, $ so tie is is S s & 9 y & Sy sys s & S Concentration (ng) Figure 1B Patent Application Publication Mar. 2, 2017. Sheet 2 of 2 US 2017/0056513 A1 0.75 eg. -
Organic Reaction Worksheet
Name _____________________________________ Date _________ Organic Reaction Worksheet 1. Fill in the table below. Be sure to complete the example reaction as well as fill in all other blanks. Be complete in your answers. Organic Description Example Reaction a. Addition CH2=CH2 + Cl2 → b.. A halogen replaces a I hydrogen on a | saturated alkane CH3CH2CH3 + ____→ CH3CHCH3 + HI c. Join many small molecules into one large molecule d. C6H12O6 + Yeast → CH3CH2OH + CO2 e. Fat + base → ____________________ f. CH3CH2COOH + CH3OH → ___________________________ + __________ g. C3H8 + 5 O2 → 3CO2 + 4H2O h. Break down large C20H42 → C8H16 + 2C3H8 hydrocarbons with heat, pressure and/or catalyst into smaller, more useful sizes 2. The process of joining many small molecules into larger molecules is called (1) neutralization (2) polymerization (3) saponification (4) substitution 3. In which reaction is soap a product? (1) addition (2) substitution (3) saponification (4) polymerization 4. Given the equation: C2H6 + Cl2 ---> C2H5Cl + HCl This reaction is best described as 1) addition involving a saturated hydrocarbon (2) addition involving an unsaturated hydrocarbon (3) substitution involving a saturated hydrocarbon (4) substitution involving an unsaturated hydrocarbon 5. Base your answers to questions a. through c. on the information below. Many artificial flavorings are prepared using the type of organic reaction shown below. a. What is the name of this organic reaction? __________________________ b. To what class of organic compounds does reactant 2 belong? ______________ c. Draw the structural formula of an isomer of reactant 2. 6. In the space to the right of the reactants and arrow draw the structural formula for the product of the reaction shown. -
Characterisation of the Reaction Mechanism Between Ammonia and Formaldehyde from the Topological Analysis of ELF and Catastrophe Theory Perspective
Struct Chem DOI 10.1007/s11224-017-1024-x ORIGINAL RESEARCH Characterisation of the reaction mechanism between ammonia and formaldehyde from the topological analysis of ELF and catastrophe theory perspective Agnieszka Ćmikiewicz1 & Agnieszka J. Gordon1 & Sławomir Berski1 Received: 11 November 2016 /Accepted: 9 August 2017 # The Author(s) 2017. This article is an open access publication Abstract A prototypical reaction between ammonia and Introduction formaldehyde has been investigated at the DFT(M06)/6- 311++G(d,p) computational level using the Bonding The reaction of ammonia with formaldehyde was investigated Evolution Theory (BET). BET is a very useful tool for study- in 1835 by Liebig [1]. Among its products were hemiaminals— ing reaction mechanisms as it combines topological analysis molecular compounds containing amino and hydroxyl groups, of electron localisation function with the catastrophe theory. bound to the same carbon. Hemiaminal is an initial product of Each of two studied reactions: H2C=O + NH3 ↔ HO–C(H2)– the reaction between aldehyde or ketone and amine. NH2 (hemiaminal) and HO–C(H2)–NH2 ↔ HN = CH2 (Schiff Hemiaminals obtained from primary amines have been gener- base) + H2O consists of six steps. Formation of hemiaminal ally considered unstable [2]. In 2010, Barys et al. [3] developed starts from a nucleophillic attack of nitrogen lone pair in NH3 a new general method for stable hemiaminals preparation. The on the carbon atom in H2C=O and is subsequently followed synthesis has been performed using 4-amino-1,2,4-triazole and by hydrogen transfer within the N–H..O bridge. A Schiff base nitro-substituted benzaldehydes in acetonitrile [3]. -
A General N-Alkylation Platform Via Copper Metallaphotoredox and Silyl Radical Activation of Alkyl Halides
ll Article A general N-alkylation platform via copper metallaphotoredox and silyl radical activation of alkyl halides Nathan W. Dow, Albert Cabre´, David W.C. MacMillan [email protected] Highlights General, room temperature N- alkylation via copper metallaphotoredox catalysis Broad reactivity across diverse alkyl bromides, N-heterocycles, and pharmaceuticals Convenient approach to N- cyclopropylation using easily handled bromocyclopropane Readily extended to functionalization of unactivated secondary alkyl chlorides Traditional substitution reactions between nitrogen nucleophiles and alkyl halides feature well-established, substrate-dependent limitations and competing reaction pathways under thermally induced conditions. Herein, we report that a metallaphotoredox approach, utilizing a halogen abstraction-radical capture (HARC) mechanism, provides a valuable alternative to conventional N-alkylation. This visible-light-induced, copper-catalyzed protocol is successful for coupling >10 classes of N-nucleophiles with diverse primary, secondary, or tertiary alkyl bromides. Moreover, this open-shell platform alleviates outstanding N-alkylation challenges regarding regioselectivity, direct cyclopropylation, and secondary alkyl chloride functionalization. Dow et al., Chem 7,1–16 July 8, 2021 ª 2021 Elsevier Inc. https://doi.org/10.1016/j.chempr.2021.05.005 Please cite this article in press as: Dow et al., A general N-alkylation platform via copper metallaphotoredox and silyl radical activation of alkyl halides, Chem (2021), https://doi.org/10.1016/j.chempr.2021.05.005 -
Synthesis of a Poison Frog Bioactive Alkaloids Sara Mazeh
Synthesis of a poison frog bioactive alkaloids Sara Mazeh To cite this version: Sara Mazeh. Synthesis of a poison frog bioactive alkaloids. Organic chemistry. Université Grenoble Alpes, 2019. English. NNT : 2019GREAV043. tel-02613846 HAL Id: tel-02613846 https://tel.archives-ouvertes.fr/tel-02613846 Submitted on 20 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THÈSE Pour obtenir le grade de DOCTEUR DE LA COMMUNAUTÉ UNIVERSITÉ GRENOBLE ALPES Spécialité : Chimie organique Arrêté ministériel : 25 mai 2016 Présentée par SARA MAZEH Thèse dirigée par Philippe DELAIR préparée au sein du Laboratoire Département de Pharmaco chimie Moléculaire dans l'École Doctorale Chimie et Sciences du Vivant Synthèse d'alcaloïdes bioactifs issus de batracien Synthesis of a poison frog bioactive alkaloids Thèse soutenue publiquement le 9 décembre 2019, devant le jury composé de : Madame MERCEDES AMAT PROFESSEUR, UNIVERSITE DE BARCELONE - ESPAGNE, Rapporteur Monsieur DAVID AITKEN PROFESSEUR DES UNIVERSITES, UNIVERSITE PARIS-SUD, Rapporteur Monsieur PETER GOEKJIAN PROFESSEUR DES UNIVERSITES, UNIVERSITE LYON 1, Examinateur Madame SANDRINE PY DIRECTRICE DE RECHERCHE, CNRS DELEGATION ALPES, Examinateur Monsieur OLIVIER RENAUDET PROFESSEUR DES UNIVERSITES, UNIVERSITE GRENOBLE ALPES, Président Monsieur PHILIPPE DELAIR MAITRE DE CONFERENCES HDR, UNIVERSITE GRENOBLE ALPES, Directeur de thèse Dedicated to my parents, this simply wouldn’t exist without you.