Cyclopropanation Chem 115

Total Page:16

File Type:pdf, Size:1020Kb

Cyclopropanation Chem 115 Myers Cyclopropanation Chem 115 Reviews: • Bonding Orbitals in Cyclopropane (Walsh Model): Roy, M.-N.; Lindsay, V. N. G.; Charette, A. B. Stereoselective Synthesis: Reactions of Carbon– Carbon Double Bonds (Science of Synthesis); de Vries, J. G., Ed.; Thieme: Stuttgart, 2011, Vol 1.; 731–817. Lebel, H.; Marcoux, J.-F.; Molinaro, C.; Charette, A. B. Chem. Rev. 2003, 103, 977–1050. Davies, H. M. L.; Beckwith, R. E. J. Chem. Rev. 2003, 103, 2861–2903. Li, A-H.; Dai, L. X.; Aggarwal, V. K. Chem. Rev. 1997, 97, 2341–2372. eS (") eA (") • Applications of Cyclopropanes in Synthesis Carson, C. A.; Kerr, M. A. Chem. Soc. Rev. 2009, 38, 3051–3060. Reissig, H.-U.; Zimmer, R. Chem. Rev. 2003, 103, 1151–1196. Gnad, F.; Reiser, O. Chem. Rev. 2003, 103, 1603–1624. • Cyclopropane Biosynthesis ! Thibodeaux, C. J.; Chang, W.-c.; Liu, H.-w. Chem. Rev. 2012, 112, 1681–1709. de Meijere, A. Angew. Chem. Int. Ed. 1979, 18, 809–886. General Strategies for Cyclopropanation: Introduction • via carbenoids "MCH2X" H HH H H H • via carbenes generated by decomposition of diazo compounds H H H H H H RCHN2 • Cyclopropanes are stable but highly strained compounds (ring strain ~29 kcal/mol). R • via Michael addition and ring closure • C–C bond angles = 60º (vs 109.5º for normal Csp3–Csp3 bonds). • Substituents on cyclopropanes are eclipsed. H–C–H angle is ~120º. As a result, the C–H bonds RCH–LG have higher s character compared to normal sp3 bonds. EWG EWG EWG LG R • Because of their inherent strain, the reactivity of cyclopropanes is more closely analogous to that of alkenes than that of alkanes. RCH2 R EWG LG EWG LG EWG R Lebel, H.; Marcoux, J.-F.; Molinaro, C.; Charette, A. B. Chem. Rev. 2003, 103, 977–1050. James Mousseau, Fan Liu 1 Myers Cyclopropanation Chem 115 Simmons-Smith Reaction –– Zinc Reagents in Cyclopropanation • Diastereoselective cyclopropanation is possible in the presence of directing groups: • Original Report: OH OH OCH3 CH3O H H CH2I2, Zn(Cu) CH2I2, Zn(Cu) H CH I , Zn(Cu) Et O, 35 ºC Et O, 35 ºC 2 2 2 H 2 H (±) 63% (±) (±) ~60% (±) Et2O, 35 ºC 48% H Dauben, W. G.; Berezin, G. H. J. Am. Chem. Soc. 1963, 85, 468–472. Simmons, H. E.; Smith, R. D. J. Am. Chem. Soc. 1958, 80, 5323–5324. • Interestingly, excess carbenoid can reverse the directing effect of alcohols. • Reaction Overview: OZnR' OZnR' OZnR' H H Zn I H R1 "ZnCH I" CH R H 2 2 1 OBn OBn OBn R1 H R H R R2 2 2 Zinc Reagent dr yield Zn(CH I) (1 equiv) >25:1 >95% Butterfly transition state 2 2 EtZnCH2I (9 equiv) 1:>25 >95% Charette, A. B.; Marcoux, J. F. Synlett, 1995, 1197–1207. • The reaction is proposed to proceed through a "butterfly" transition state. • Directed cyclopropanation is also possible in acyclic systems: Simmons, H. E. Org. React. 1973, 20, 1–133. OH OH OH CH • Zinc cyclopropanating reagents can be generated in various ways. Both Zn metal and ZnEt can be Et2Zn, CH2I2 3 2 CH3 CH3 used. CH Cl , –10 °C H 2 2 H 97% : • Many zinc reagents for cyclopropanation have been developed: 130 1 Charette, A. B.; Lebel, H. J. Org. Chem. 1995, 60, 2966–1967. • Diastereoselectrive cyclopropanation has been used in tandem asymmetric organozinc additions: O O I Zn I I EtO Zn Zn F C P I 3 Zn Zn 1. HBEt , PhCH , 23 ºC I H3C EtO 2 3 I I OH Simmons 2. Et2Zn, i-PrCHO ZnEt2, CH2I2 OH and Smith Denmark Furukawa Shi Charette CH3 H3C CH3 Ph CH Cl , 23 ºC CH3 Ph 2 2 Ph O CH3 N H CH3 Highly reactive OH carbenoid for Highly stable carbenoid 75%, 99% ee H3C (4 mol%) General applicability unreactive alkenes dr >20:1 –78 ! –10 ºC Kim, H. Y.; Lurain, A. E.; Garcia-Garcia, P.; Carroll, P. J.; Walsh, P. J. J. Am. Chem. Soc. 2005, 127, 13138–13139. James Mousseau, Fan Liu 2 Myers Cyclopropanation Chem 115 • Asymmetric Simmons-Smith Reaction Using Chiral Auxiliaries • Stoichiometric Promoter for Asymmetric Simmons-Smith Cyclopropanation • Allylic alcohols: • A chiral dioxaborolane auxiliary prepared from tetramethyltartramide and butylboronic acid has been shown to be effective in the asymmetric cyclopropanation of allylic alcohols. • A hydrogen peroxide work-up is employed to remove boron side-products. OBn OBn Et Zn, CH I O 2 2 2 O A (1.1 equiv) BnO O Ph BnO O Ph BnO BnO H OH toluene, –35 ! 0 ºC OH Zn(CH2I)2, DME, CH2Cl2 98%, dr >50:1 OH OH 0 ! 23 ºC 1. Tf O, C H N >98%, 93% ee 2 5 5 then 30% aq H O 2. 2 2 via OBn DMF, H2O, C5H5N Me 160 ºC, 90% O Et BnO O OBn via O BnO Me O O H3C O HO Ph N(CH ) EtZn Zn O N(CH ) O 3 2 C + BnO (H3C)2N 3 2 B H I BnO 2 CHO O O O O H B Zn O N(CH3)2 A I Charette, A. B.; Côté, B.; Marcoux, J.-F. J. Am. Chem. Soc. 1991, 113, 8166–8167. n-Bu Ph H • Allylic amines: Charette, A. B.; Juteau, H.; Lebel, H.; Molinaro, C. J. Am. Chem. Soc. 1998, 120, 11943–11952. Ph OH Ph OH • Allylic alcohols are cyclopropanated selectively: Et2Zn, CH2I2 H3C N Ph H3C N Ph CH2Cl2, 0 °C CH3 CH3 ent-A (1.1 equiv) 95%, dr = 98:2 CH3 CH3 CH3 H3C Zn(CH2I)2, DME, CH2Cl2 H3C H H3C Aggarwal, V. K.; Fang, G. Y.; Meek, G. Org. Lett. 2003, 5, 4417–4420. then 30% aq H O OH 2 2 80%, 95% ee OH • ",#-Unsaturated carbonyls: 1. (EtO)3CH, NH4NO3 (cat.) H C EtOH, 23 ºC 3 O Nicolaou, K. C.; Sasmal, P. K.; Rassais, G.; Reddy, M. V.; Altmann, K. H.; Wartmann, M.; O'Brate, H3C H CO2i-Pr O A.; Giannakakou, P. Angew. Chem. Int. Ed. 2003, 42, 3515–3520. O 2. OH CO2i-Pr CO2i-Pr • The cyclopropanation of allenic alcohols affords spiropentane derivatives: i-PrO2C OH Et2Zn, CH2I2 C5H5NH•OTs, C6H6 hexanes, –20 °C OH 80 ºC, 79% A (1.1 equiv) MO Et OH Et Zn(CH2I)2, DME, CH2Cl2 C Et H H3C O H pTSA, THF Et H –10 ! 23 ºC Et H C CO2i-Pr Et 3 H O then 10% aq NaOH H O, 65 ºC 70%, 97% ee O 2 yield not provided CO2i-Pr 90%, dr = 97:3 Mash, E. A.; Nelson, K. A. J. Am. Chem. Soc. 1985, 107, 8256–8258. Charette, A. B.; Jolicoeur, E.; Bydlinkski, G. A. S. Org. Lett. 2001, 3, 3293–3295 Mori, A.; Arai, I.; Yamamoto, H. Tetrahedron 1986, 42, 6447–6458. James Mousseau, Fan Liu 3 Myers Cyclopropanation Chem 115 • The dioxaborolane promoter can be used to prepare 1,2,3-trisubstituted cyclopropanes. • Unfunctionalized alkenes can undergo asymmetric Simmons–Smith cyclopropanation in presence of • In the example shown, the intermediate borinate was used directly for Suzuki coupling: a valine/proline dipeptide. • Selectivity is higher for trisubstituted alkenes than for disubstituted alkenes. O O (H3C)2N N(CH3)2 Ph C (1.25 equiv) Ph O CO2CH3 BocHN 1. Et2Zn 2. A (1.2 equiv) O O Et2Zn, CH2I2 N Ph OH Ph OZnEt B n-Bu CH2Cl2, 0 ºC Ph O 0 ºC, CH2Cl2 H3C CH3 ZnEt 83%, 90% ee absolute stereochemistry C not reported O O n-Bu 3. EtZnI•OEt , CHI H (H C) N N(CH ) 2 3 H B 3 2 3 2 B-Zn Exchange CH2Cl2, –78 ! –40 ºC Long, J.; Yuan, Y.; Shi, Y. J. Am. Chem. Soc. 2003, 125, 13632–13633. O ZnI Ph O O H B Ph O n-Bu • Catalytic Enantioselective Simmons-Smith Cyclopropanation Reactions ZnEt • Chiral bis-sulfonamides have been used to direct asymmetric Simmons–Smith reactions of allylic 4. Pd(PPh3)4 alcohols: (5 mol%) Ph PhI, KOH Ph OH D (10 mol %) THF, 65 ºC 59%, 92% ee, >20:1 dr Et Zn, ZnI , Zn(CH I) 2 2 2 2 NHSO2CH3 OH OH CH2Cl2, 0 ºC Zimmer, L. E.; Charette, A. B. J. Am. Chem. Soc. 2009, 131, 15624–15626. NHSO CH 92%, 89% ee 2 3 • Homoallylic ethers can be cyclopropanated using a zinc phosphate, prepared in situ from a chiral D phosphoric acid: B (1.2 equiv) OBn Et2Zn, CH2I2 OBn Denmark, S. E.; O'Connor, S. P. J. Org. Chem. 1997, 62, 584–594. CH2Cl2, 0 ºC 85%, 93% ee • "Taddolates" can also be used: E Et Et B via E (25 mol %) O O Ar Ar = Ar Zn(CH I) , 4Å MS Ph Ph OH 2 2 OH O O O O Ph Ph P P CH2Cl2, 0 ºC O O O OH O OZnCH I Ti 2 85%, 92% ee i-PrO Oi-Pr Ar Ar Charette, A. B.; Molinaro, C.; Brochu, C. J. Am. Chem. Soc. 2001, 123, 12168–12175. Lacasse, M.-C.; Poulard, C. Charette, A. B. J. Am. Chem. Soc. 2005, 127, 12440–12441. James Mousseau, Fan Liu 4 Myers Cyclopropanation Chem 115 • A bifunctional Al-complex is an effective cyclopropanation catalyst and is believed to bind both the • Telluronium ylides can also be used: Zn and the allylic alcohol: ligand (10 mol%) Et2AlCl (10 mol%) H3C TBDPSO TBDPSO 1. LiTMP, HMPA CO2Et OH + Et Zn, CH I OH Te TMS 2 2 2 THF, toluene, –95 ºC CH Cl , 23 ºC 2 2 CH TMS 3 2. CO Et 99%, 90% ee 2 O ligand O 81%, 97% ee NH N via O OH HO I Ph Ph N N Zn Al Liao, W.-W.; Li, K.
Recommended publications
  • United States Patent Office Patented June 17, 1969
    3,450,782 United States Patent Office Patented June 17, 1969 2 1,3-dibromocyclobutane with sodium in refluxing dioxane, 3,450,782 PROCESS FOR THE PREPARATION OF K. B. Wiberg, G. M. Lampman, R. P. Ciula, D. S. Con CYCLICALKANES nor, P. Scherter, and J. Lavanesh, Tetrahedron, 21, 2749 Daniel S. Connor, Cincinnati, Ohio, assignor to The (1695), bicyclo[1.1.1 pentane by treatment of 3-(bromo Procter & Gamble Company, Cincinnati, Ohio, a cor methyl)-cyclobutyl bromide with sodium metal at a 0.5% poration of Ohio yield, with lithium amalgam in refluxing dioxane at a No Drawing. Filed Nov. 29, 1967, Ser. No. 686,738 4.2% yield and with sodium/naphtahalene at a 8% yield, Int, C. C07c I/28 K. B. Wiberg, D. S. Connor, and G. M. Lampman, Tetra U.S. C. 260-666 8 Claims hedron Letters, 531 (1964); K. B. Wiberg and D. S. Con 0 nor, J. Am. Chem. Soc., 88, 4437 (1966). On examination of the literature hereinbefore cited ABSTRACT OF THE DISCLOSURE on cyclization, it is apparent that the yields obtained were This invention concerns the preparation of cyclic al extremely low, that the conditions for reaction when it kanes from dihalogenated alkanes using lithium amalgam. did occur were quite severe, and that the starting materials 5 used were less than common. OBJECTS OF THE INVENTION SUMMARY OF THE INVENTION The use of the method of this invention to obtain cyclic The object of this invention is to prepare cyclic al compounds provides a valuable synthetic tool heretofore kanes from the halogenated straight chain starting ma 20 unknown to chemists, thus enabling the production of terials using lithium amalgam to remove the halogens valuable end products.
    [Show full text]
  • Carbene and Nitrene Transfer Reactions Joseph B
    University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School 11-19-2014 Co(II) Based Metalloradical Catalysis: Carbene and Nitrene Transfer Reactions Joseph B. Gill University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the Organic Chemistry Commons Scholar Commons Citation Gill, Joseph B., "Co(II) Based Metalloradical Catalysis: Carbene and Nitrene Transfer Reactions" (2014). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/5484 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Co(II) Based Metalloradical Catalysis: Carbene and Nitrene Transfer Reactions by Joseph B. Gill A dissertation in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Chemistry College of Arts and Sciences University of South Florida Major Professor: X. Peter Zhang, Ph.D. Jon Antilla, Ph.D Jianfeng Cai, Ph.D. Edward Turos, Ph.D. Date of Approval: November 19, 2014 Keywords: cyclopropanation, diazoacetate, azide, porphyrin, cobalt. Copyright © 2014, Joseph B. Gill Dedication I dedicate this work to my parents: Larry and Karen, siblings: Jason and Jessica, and my partner: Darnell, for their constant support. Without all of you I would never have made it through this journey. Thank you. Acknowledgments I would like to thank my advisor, Professor X. Peter Zhang, for his support and guidance throughout my time working with him.
    [Show full text]
  • Supporting Information
    Electronic Supplementary Material (ESI) for RSC Advances. This journal is © The Royal Society of Chemistry 2021 Supporting Information Synthesis, Oligomerization and Catalytic Studies of a Redox- Active Ni4-Cubane: A detailed Mechanistic Investigation Saroj Kumar Kushvaha, a† Maria Francis, b† Jayasree Kumar, a Ekta Nag, b Prathap Ravichandran, a b a Sudipta Roy* and Kartik Chandra Mondal* aDepartment of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India. bDepartment of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati 517507, India. † Both authors contributed equally. Table of Contents 1. General remarks 2. Syntheses of complexes 1-3 3. Detail characterization of complexes 1-3 4. Computational details 5. X-ray single crystal diffraction of complexes 1-3. 6. Details of catalytic activities of complex 3 6.1. General procedures for the syntheses of aromatic heterocycles (6) and various diazoesters (7) 6.2. Optimization of reaction condition for cyclopropanation of aromatic heterocycles (6) 6.3. General synthetic procedure and characterization data for cyclopropanated aromatic heterocycles (8) 6.4. Determination of relative stereochemistry of 8 7. 1H and 13C NMR spectra of compounds 8a-j 8. Mechanistic investigations and mass spectrometric analysis 9. References S1 1. General remarks All catalytic reactions were performed under Argon atmosphere. The progress of all the catalytic reactions were monitored by thin layer chromatography (TLC, Merck silica gel 60 F 254) upon visualization of the TLC plate under UV light (250 nm). Different charring reagents, such as phosphomolybdic acid/ethanol, ninhydrin/acetic acid solution and iodine were used to visualize various starting materials and products spots on TLC plates.
    [Show full text]
  • Gold-Catalyzed Ethylene Cyclopropanation
    Gold-catalyzed ethylene cyclopropanation Silvia G. Rull, Andrea Olmos* and Pedro J. Pérez* Full Research Paper Open Access Address: Beilstein J. Org. Chem. 2019, 15, 67–71. Laboratorio de Catálisis Homogénea, Unidad Asociada al CSIC, doi:10.3762/bjoc.15.7 CIQSO-Centro de Investigación en Química Sostenible and Departamento de Química, Universidad de Huelva, Campus de El Received: 17 October 2018 Carmen 21007 Huelva, Spain Accepted: 11 December 2018 Published: 07 January 2019 Email: Andrea Olmos* - [email protected]; Pedro J. Pérez* - This article is part of the thematic issue "Cyclopropanes and [email protected] cyclopropenes: synthesis and applications". * Corresponding author Guest Editor: M. Tortosa Keywords: © 2019 Rull et al.; licensee Beilstein-Institut. carbene transfer; cyclopropane; cyclopropylcarboxylate; ethylene License and terms: see end of document. cyclopropanation; ethyl diazoacetate; gold catalysis Abstract Ethylene can be directly converted into ethyl 1-cyclopropylcarboxylate upon reaction with ethyl diazoacetate (N2CHCO2Et, EDA) F F in the presence of catalytic amounts of IPrAuCl/NaBAr 4 (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene; BAr 4 = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate). Introduction Nowadays the olefin cyclopropanation through metal-catalyzed carbene transfer starting from diazo compounds to give olefins constitutes a well-developed tool (Scheme 1a), with an exquisite control of chemo-, enantio- and/or diastereoselectiv- ity being achieved [1,2]. Previous developments have involved a large number of C=C-containing substrates but, to date, the methodology has not been yet employed with the simplest olefin, ethylene, for synthetic purposes [3]. Since diazo compounds bearing a carboxylate substituent are the most Scheme 1: (a) General metal-catalyzed olefin cyclopropanation reac- commonly employed carbene precursors toward olefin cyclo- tion with diazo compounds.
    [Show full text]
  • Organic Synthesis: New Vistas in the Brazilian Landscape
    Anais da Academia Brasileira de Ciências (2018) 90(1 Suppl. 1): 895-941 (Annals of the Brazilian Academy of Sciences) Printed version ISSN 0001-3765 / Online version ISSN 1678-2690 http://dx.doi.org/10.1590/0001-3765201820170564 www.scielo.br/aabc | www.fb.com/aabcjournal Organic Synthesis: New Vistas in the Brazilian Landscape RONALDO A. PILLI and FRANCISCO F. DE ASSIS Instituto de Química, UNICAMP, Rua José de Castro, s/n, 13083-970 Campinas, SP, Brazil Manuscript received on September 11, 2017; accepted for publication on December 29, 2017 ABSTRACT In this overview, we present our analysis of the future of organic synthesis in Brazil, a highly innovative and strategic area of research which underpins our social and economical progress. Several different topics (automation, catalysis, green chemistry, scalability, methodological studies and total syntheses) were considered to hold promise for the future advance of chemical sciences in Brazil. In order to put it in perspective, contributions from Brazilian laboratories were selected by the citations received and importance for the field and were benchmarked against some of the most important results disclosed by authors worldwide. The picture that emerged reveals a thriving area of research, with new generations of well-trained and productive chemists engaged particularly in the areas of green chemistry and catalysis. In order to fulfill the promise of delivering more efficient and sustainable processes, an integration of the academic and industrial research agendas is to be expected. On the other hand, academic research in automation of chemical processes, a well established topic of investigation in industrial settings, has just recently began in Brazil and more academic laboratories are lining up to contribute.
    [Show full text]
  • And Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis Xue Xu University of South Florida, [email protected]
    University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School January 2012 Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis Xue Xu University of South Florida, [email protected] Follow this and additional works at: http://scholarcommons.usf.edu/etd Part of the American Studies Commons, and the Organic Chemistry Commons Scholar Commons Citation Xu, Xue, "Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis" (2012). Graduate Theses and Dissertations. http://scholarcommons.usf.edu/etd/4262 This Dissertation is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Asymmetric Intra- and Intermolecular Cyclopropanation by Co(II)- Based Metalloradical Catalysis by Xue(Snow) Xu A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Chemistry College of Arts and Sciences University of South Florida Major Professor: X. Peter Zhang, Ph.D. Jon Antilla, Ph.D. Mark L. McLaughlin, Ph.D. Wayne Guida, Ph.D. Date of Defense: June 20th, 2012 Keywords: cobalt, porphyrin, catalysis, cyclopropanation, carbene, diazo Copyright © 2012, Xue Xu DEDICATION I dedicate this dissertation to my parents and my husband, without their caring support, it would not have been possible. ACKNOWLEGEMENTS I need to begin with thanking Dr. Peter Zhang for his continuous guidance and support over the last 5 and half years. Especially for encouraging me to achieving my potential as a researcher and setting an example of dedication to science that is admirable.
    [Show full text]
  • Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc
    Metal-Metal (MM) Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc Richard H. Duncan Lyngdoh*,a, Henry F. Schaefer III*,b and R. Bruce King*,b a Department of Chemistry, North-Eastern Hill University, Shillong 793022, India B Centre for Computational Quantum Chemistry, University of Georgia, Athens GA 30602 ABSTRACT: This survey of metal-metal (MM) bond distances in binuclear complexes of the first row 3d-block elements reviews experimental and computational research on a wide range of such systems. The metals surveyed are titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, and zinc, representing the only comprehensive presentation of such results to date. Factors impacting MM bond lengths that are discussed here include (a) n+ the formal MM bond order, (b) size of the metal ion present in the bimetallic core (M2) , (c) the metal oxidation state, (d) effects of ligand basicity, coordination mode and number, and (e) steric effects of bulky ligands. Correlations between experimental and computational findings are examined wherever possible, often yielding good agreement for MM bond lengths. The formal bond order provides a key basis for assessing experimental and computationally derived MM bond lengths. The effects of change in the metal upon MM bond length ranges in binuclear complexes suggest trends for single, double, triple, and quadruple MM bonds which are related to the available information on metal atomic radii. It emerges that while specific factors for a limited range of complexes are found to have their expected impact in many cases, the assessment of the net effect of these factors is challenging.
    [Show full text]
  • Benchmarking and Application of Density Functional Methods In
    BENCHMARKING AND APPLICATION OF DENSITY FUNCTIONAL METHODS IN COMPUTATIONAL CHEMISTRY by BRIAN N. PAPAS (Under Direction the of Henry F. Schaefer III) ABSTRACT Density Functional methods were applied to systems of chemical interest. First, the effects of integration grid quadrature choice upon energy precision were documented. This was done through application of DFT theory as implemented in five standard computational chemistry programs to a subset of the G2/97 test set of molecules. Subsequently, the neutral hydrogen-loss radicals of naphthalene, anthracene, tetracene, and pentacene and their anions where characterized using five standard DFT treatments. The global and local electron affinities were computed for the twelve radicals. The results for the 1- naphthalenyl and 2-naphthalenyl radicals were compared to experiment, and it was found that B3LYP appears to be the most reliable functional for this type of system. For the larger systems the predicted site specific adiabatic electron affinities of the radicals are 1.51 eV (1-anthracenyl), 1.46 eV (2-anthracenyl), 1.68 eV (9-anthracenyl); 1.61 eV (1-tetracenyl), 1.56 eV (2-tetracenyl), 1.82 eV (12-tetracenyl); 1.93 eV (14-pentacenyl), 2.01 eV (13-pentacenyl), 1.68 eV (1-pentacenyl), and 1.63 eV (2-pentacenyl). The global minimum for each radical does not have the same hydrogen removed as the global minimum for the analogous anion. With this in mind, the global (or most preferred site) adiabatic electron affinities are 1.37 eV (naphthalenyl), 1.64 eV (anthracenyl), 1.81 eV (tetracenyl), and 1.97 eV (pentacenyl). In later work, ten (scandium through zinc) homonuclear transition metal trimers were studied using one DFT 2 functional.
    [Show full text]
  • Catalytic Cyclopropanation of Polybutadienes
    Erschienen in: Journal of Polymer Science, Part A: Polymer Chemistry ; 48 (2010), 20. - S. 4439-4444 https://dx.doi.org/10.1002/pola.24231 Catalytic Cyclopropanation of Polybutadienes JUAN URBANO,1 BRIGITTE KORTHALS,2 M. MAR DI´AZ-REQUEJO,1 PEDRO J. PE´ REZ,1 STEFAN MECKING2 1Laboratorio de Cata´ lisis Homoge´ nea, Departamento de Quı´mica y Ciencia de los Materiales, Unidad Asociada al CSIC, Centro de Investigacio´ n en Quı´mica Sostenible, Campus de El Carmen s/n, Universidad de Huelva, 21007 Huelva, Spain 2Department of Chemistry, University of Konstanz, 78464 Konstanz, Germany ABSTRACT: Catalytic cyclopropanation of commercial 1,2- or 1,4- bonyl-cyclopropene)]. Catalytic hydrogenation of residual dou- cis-polybutadiene, respectively, with ethyl diazoacetate catalyzed ble bonds of partially cyclopropanated polybutadienes provided by [TpBr3Cu(NCMe)] (TpBr3 ¼ hydrotris(3,4,5-tribromo-1-pyrazo- access to the corresponding saturated polyolefins. Thermal lyl)borate) at room temperature afforded high molecular weight properties are reported. 5 À1 (Mn > 10 mol ) side-chain or main-chain, respectively, carbox- yethyl cyclopropyl-substituted polymers with variable and con- trolled degrees of functionalization. Complete functionalization KEYWORDS: carbene addition; catalysis; functionalization of poly- of 1,4-cis-polybutadiene afforded poly[ethylene-alt-(3-ethoxycar- mers; organometallic catalysis; polar groups; polybutadienes INTRODUCTION Catalytic insertion polymerization of ethyl- polypropylene.6 Examples of catalytic post-polymerization ene and propylene is employed for the production of more reactions on saturated polyolefins are rare. The oxyfunction- than 60 million tons of polyolefins annually.1 These poly- alization of polyethylenes and polypropylenes by metal- mers are hydrocarbons, without any heteroatom-containing based catalysts can afford hydroxyl groups.7 We have functional groups, such as for example ester moieties.
    [Show full text]
  • Recent Advances on Mechanistic Studies on C–H Activation
    Open Chem., 2018; 16: 1001–1058 Review Article Open Access Daniel Gallego*, Edwin A. Baquero Recent Advances on Mechanistic Studies on C–H Activation Catalyzed by Base Metals https:// doi.org/10.1515/chem-2018-0102 received March 26, 2018; accepted June 3, 2018. 1Introduction Abstract: During the last ten years, base metals have Application in organic synthesis of transition metal- become very attractive to the organometallic and catalytic catalyzed cross coupling reactions has been positioned community on activation of C-H bonds for their catalytic as one of the most important breakthroughs during the functionalization. In contrast to the statement that new millennia. The seminal works based on Pd–catalysts base metals differ on their mode of action most of the in the 70’s by Heck, Noyori and Suzuki set a new frontier manuscripts mistakenly rely on well-studied mechanisms between homogeneous catalysis and synthetic organic for precious metals while proposing plausible chemistry [1-5]. Late transition metals, mostly the precious mechanisms. Consequently, few literature examples metals, stand as the most versatile catalytic systems for a are found where a thorough mechanistic investigation variety of functionalization reactions demonstrating their have been conducted with strong support either by robustness in several applications in organic synthesis [6- theoretical calculations or experimentation. Therefore, 12]. Owing to the common interest in the catalysts mode we consider of highly scientific interest reviewing the of action by many research groups, nowadays we have a last advances on mechanistic studies on Fe, Co and Mn wide understanding of the mechanistic aspects of precious on C-H functionalization in order to get a deep insight on metal-catalyzed reactions.
    [Show full text]
  • Revised Group Additivity Values for Enthalpies of Formation (At 298 K) of Carbon– Hydrogen and Carbon–Hydrogen–Oxygen Compounds
    Revised Group Additivity Values for Enthalpies of Formation (at 298 K) of Carbon– Hydrogen and Carbon–Hydrogen–Oxygen Compounds Cite as: Journal of Physical and Chemical Reference Data 25, 1411 (1996); https://doi.org/10.1063/1.555988 Submitted: 17 January 1996 . Published Online: 15 October 2009 N. Cohen ARTICLES YOU MAY BE INTERESTED IN Additivity Rules for the Estimation of Molecular Properties. Thermodynamic Properties The Journal of Chemical Physics 29, 546 (1958); https://doi.org/10.1063/1.1744539 Critical Evaluation of Thermochemical Properties of C1–C4 Species: Updated Group- Contributions to Estimate Thermochemical Properties Journal of Physical and Chemical Reference Data 44, 013101 (2015); https:// doi.org/10.1063/1.4902535 Estimation of the Thermodynamic Properties of Hydrocarbons at 298.15 K Journal of Physical and Chemical Reference Data 17, 1637 (1988); https:// doi.org/10.1063/1.555814 Journal of Physical and Chemical Reference Data 25, 1411 (1996); https://doi.org/10.1063/1.555988 25, 1411 © 1996 American Institute of Physics for the National Institute of Standards and Technology. Revised Group Additivity Values for Enthalpies of Formation (at 298 K) of Carbon-Hydrogen and Carbon-Hydrogen-Oxygen Compounds N. Cohen Thermochemical Kinetics Research, 6507 SE 31st Avenue, Portland, Oregon 97202-8627 Received January 17, 1996; revised manuscript received September 4, 1996 A program has been undertaken for the evaluation and revision of group additivity values (GAVs) necessary for predicting, by means of Benson's group additivity method, thermochemical properties of organic molecules. This review reports on the portion of that program dealing with GAVs for enthalpies of formation at 298.15 K (hereinafter abbreviated as 298 K) for carbon-hydrogen and carbon-hydrogen-oxygen compounds.
    [Show full text]
  • Experimental and Ab Initio Studies of Formation, Thermolysis, and Molecular and Electronic Structures of 3,6-Diphenyl-1-Propanesulfenimido-1,2,4,5-Tetrazine
    J. Am. Chem. Soc. 2000, 122, 2087-2095 2087 Nucleophile-Induced Intramolecular Dipole 1,5-Transfer and 1,6-Cyclization: Experimental and ab Initio Studies of Formation, Thermolysis, and Molecular and Electronic Structures of 3,6-Diphenyl-1-propanesulfenimido-1,2,4,5-tetrazine Piotr Kaszynski*,† and Victor G. Young, Jr.‡ Contribution from the Organic Materials Research Group, Department of Chemistry, Vanderbilt UniVersity, NashVille, Tennessee 37235, and X-ray Crystallographic Laboratory, Department of Chemistry, UniVersity of Minnesota, Twin Cities, Minnesota 55455 ReceiVed NoVember 1, 1999 Abstract: Reaction of dichlorobenzaldazine (2) with sodium azide followed by 1-propanethiol/Et3N furnished tetrazine ylide 1 as the main product. The structure of this unprecedented ylide was confirmed with single- crystal X-ray analysis [C17H17N5S, monoclinic P21/na) 6.8294(4) Å, b ) 13.6781(9) Å, c ) 17.5898(12) Å, â ) 90.666(1)°, Z ) 4] and favorably compared with the results of ab initio calculations. The mechanisms of formation of the ylide and its thermal decomposition to 2,5-diphenyltetrazine (5) were investigated using ab initio methods and correlated with the experimental observations. The results suggest that formation of 1 involves intramolecular cyclization of a nitrile imine and thermolysis of 1 might generate a sulfenylnitrene. The formation of 1 is considered to be the first example of a potentially more general reaction. Introduction Results and Discussion Intramolecular reactions of 1,3-dipoles provide one of the Synthesis of 1. 3,6-Diphenyl-1-propanesulfenimido-1,2,4,5- most versatile ways to construct heterocyclic rings.1 Among tetrazine (1) was obtained in a one-pot reaction.
    [Show full text]