DOCSLIB.ORG

Radical Hydroxymethylation of Alkyl Iodides Using Formaldehyde As a C1 Synthon† Cite This: Chem

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Radical Hydroxymethylation of Alkyl Iodides Using Formaldehyde As a C1 Synthon† Cite This: Chem Chemical Science View Article Online EDGE ARTICLE View Journal | View Issue Radical hydroxymethylation of alkyl iodides using formaldehyde as a C1 synthon† Cite this: Chem. Sci.,2021,12, 10448 a a a b All publication charges for this article Lewis Caiger, Conar Sinton, Timothee´ Constantin, James J. Douglas, have been paid for by the Royal Society Nadeem S. Sheikh,c Fabio Julia a and Daniele Leonori *a of Chemistry ´ Radical hydroxymethylation using formaldehyde as a C1 synthon is challenging due to the reversible and endothermic nature of the addition process. Here we report a strategy that couples alkyl iodide building blocks with formaldehyde through the use of photocatalysis and a phosphine additive. Halogen-atom Received 7th June 2021 transfer (XAT) from a-aminoalkyl radicals is leveraged to convert the iodide into the corresponding Accepted 6th July 2021 open-shell species, while its following addition to formaldehyde is rendered irreversible by trapping the DOI: 10.1039/d1sc03083c transient O-radical with PPh3. This event delivers a phosphoranyl radical that re-generates the alkyl rsc.li/chemical-science radical and provides the hydroxymethylated product. Creative Commons Attribution 3.0 Unported Licence. Introduction thus requires a subsequent stoichiometric hydride reduction step (Scheme 1B, path b).9 Hydroxymethyl motifs are frequently encountered in the core The difficulties in using formaldehyde as a C1 synthon for structure of natural products and drugs and commonly used as radical hydroxymethylation (Scheme 1B, path c) come from the 9a,10 handles for further derivatisation (Scheme 1A).1 This structural reversible nature of the addition process. According to our and practical relevance makes the development of methods able computational studies, the reaction between cyclohexyl radicals B to introduce the “CH2OH” fragment onto advanced building and HCHO ( ) is kinetically accelerated compared to the reac- blocks impactful to the discovery and development of high- tion with CO (A) but, crucially, endothermic with a later tran- value materials.2 sition state character (as determined by comparison of the This article is licensed under a 11 Retrosynthetically, the most direct approach to achieve respective d(C–C) values) (Scheme 1C). This means that the programmable small-molecule hydroxymethylation is through back reaction, involving b-scission of the primary O-radical C,is 3 3 Open Access Article. Published on 06 2021. Downloaded 2021/9/30 7:01:08. the formation of a sp –sp C–C bond with an oxygenated C1 a fast process which hampers reaction development. Overall, synthon.3 Within the realm of radical chemistry, a-hydrox- this mechanistic challenge has impacted the practical ways we ymethyl radicals, which are easily generated from MeOH via conduct hydroxymethylation with HCHO, which is generally HAT (H-atom transfer), have been successfully applied to the achieved using Grignard or organolithium reagents that might 12 functionalisation of Giese4 and Minisci5 acceptors (Scheme 1B, limit functional group compatibility (Scheme 1B, path d). path a). A signicantly less explored avenue is the development We have recently demonstrated that alkyl radicals can be of methodologies where C-radicals react with C1 SOMOphiles.6 conveniently accessed from the corresponding halides using Considering the three most atom-economic and abundant halogen-atom transfer (XAT) with a-aminoalkyl radicals 13 oxygenated C1 synthons – CO2, CO and HCHO – CO is the (Scheme 1D). These open-shell species can be generated from most used in radical strategies. Indeed, while radical the corresponding amines by SET (single-electron transfer) 7 14 15 addition to CO2 is endothermic, reaction with CO is both oxidation and deprotonation and display an abstracting kinetically and thermodynamically facile and, as demonstrated prole similar to that of tin radicals in the homolytic activation by the pioneering work of Ryu, also compatible for application of organic halides. This reactivity mode benets from a polar- 13,16 in radical chain propagations.8 This approach however, ised transition state with signicant charge-transfer char- provides the aldehyde as the product of the radical process and acter and can be used in redox-neutral photoredox manifolds and also as an initiation mechanism in transformation based on radical-chain propagations.13b aDepartment of Chemistry, University of Manchester, Manchester M13 9PL, UK. We recently became interested in benchmarking XAT reac- E-mail: [email protected]; Web: https://leonorigroup.com bEarly Chemical Development, Pharmaceuticals Sciences, R&D, AstraZeneca, tivity with the aim of enabling radical couplings between alkyl Maccleseld, UK halides and HCHO. Here we demonstrate the realisation of this cDepartment of Chemistry, College of Science, King Faisal University, P. O. Box 400, Al- goal and report the development of a practical approach for Ahsa 31982, Saudi Arabia direct radical hydroxymethylation (Scheme 1E). The process † Electronic supplementary information (ESI) available. See DOI: sequentially exploits XAT to generate an alkyl radical and then 10.1039/d1sc03083c 10448 | Chem. Sci.,2021,12,10448–10454 © 2021 The Author(s). Published by the Royal Society of Chemistry View Article Online Edge Article Chemical Science Creative Commons Attribution 3.0 Unported Licence. Scheme 1 (A) Examples of natural products and therapeutic agents containing the hydroxymethyl motif. (B) Overview of the main methods to install a hydroxymethyl motif using radical chemistry. (C) Radical addition to CO is possible while addition to HCHO is difficult due to reversibility. (D) a-Aminoalkyl radicals enable XAT activation of alkyl iodides and bromides and the corresponding carbon radicals can be engaged in several This article is licensed under a transformations. (E) This work shows the utilisation of XAT and phosphoranyl radical chemistry for the direct coupling of unactivated alkyl iodides with HCHO. Open Access Article. Published on 06 2021. Downloaded 2021/9/30 7:01:08. harnesses the ability of PPh3 to trap the resulting O-radical. This transfer) with the amine D. Since O-radicals undergo related À À approach effectively renders the radical addition to HCHO an HAT reactions at fast rates (108 M 1 s 1)17 and the amine irreversible process. Crucially, the ensuing phosphoranyl would be used in excess, this step should provide 2 whilst radical is able to sustain a radical chain propagation based on regenerating the chain-carrying a-aminoalkyl radical E. XAT to give the hydroxymethylated product. We started our investigations using 1 as the iodide, 4CzIPN as the photocatalyst and paraformaldehyde in CH3CN–H2O (10 : 1) solvent under blue light irradiation at room temperature Results and discussion 2 (Scheme 2B). Pleasingly, using Et3N as the amine, alcohol was Mechanistic considerations and reaction optimization formed in moderate yield which was improved by using i-Pr2NEt In approaching the development of a radical hydrox- (entries 1 and 2). In accordance with our mechanistic picture, ffi ymethylation reaction using HCHO as a C1 synthon, we initially evaluation of amines that can act as e cient electron donors for * a considered the utilisation of a reductive quenching photoredox 4CzIPN but cannot lead to the formation of an -aminoalkyl cycle (Scheme 2A). In principle, this manifold would enable the radical (by either oxidation and deprotonation or HAT) led to no ¼ generation of the key a-aminoalkyl radical (D / E) for XAT with product formation [compare entries 3 (TMP tetramethylpi- the alkyl iodide (e.g. 4-iodo-N-Boc-piperidine 1). According to peridine) and 4 (Ph3N) with 2 (i-Pr2NEt)]. Unfortunately, evalu- 11 our previous work, this step should be facile and provide radical ation of the other reaction parameters did not further improve ffi F along with the iminium iodide G. Addition of F to HCHO is the e ciency of the process which likely underscores the chal- reversible making a potential SET reduction (followed by lenges in overcoming the reversibility of the radical addition F $ H protonation) of the O-radical H with the reduced photocatalyst process ( + HCHO ). b challenging. However, our interest was drawn by the fact that We therefore proposed to overcome the unwanted -frag- H this mechanism could potentially benet from radical-chain mentation by trapping the transient O-radical with an reactivity where H undergoes polarity matched HAT (H-atom immediate reaction. Speci cally, we were interested by the well- © 2021 The Author(s). Published by the Royal Society of Chemistry Chem. Sci.,2021,12,10448–10454 | 10449 View Article Online Chemical Science Edge Article Creative Commons Attribution 3.0 Unported Licence. This article is licensed under a Open Access Article. Published on 06 2021. Downloaded 2021/9/30 7:01:08. Scheme 2 (A) Mechanistic proposal for the coupling of alkyl iodides with HCHO using XAT and phosphoranyl radical chemistry. (B) Optimisation of the radical coupling between iodide 1 and HCHO. (C) Literature rate constants for the reaction of O-radical with P(III) compounds to give phosphoranyl radicals. (D) Experimental and calculated properties of phosphoranyl radicals suggest XAT as the alkyl iodide activation mechanism. (E) “Reductant-free” reaction for hydroxymethylation of alkyl iodides via phosphoranyl radicals. known ability of phosphines to trap O-radicals at diffusion- halides has not been reported before,21 we speculated that their controlled rates leading to the corresponding phosphoranyl high nucleophilic character22 should lead to polar effects related radicals (Scheme 2C).18 These open-shell intermediates can still to those demonstrated in abstraction reactions with tin, silicon undergo b-scission across the sp3 C–O bond but the feasibility and a-aminoalkyl radicals.13a of this process depends on the nature of the ensuing C-radical, This mechanistic proposal was validated by the addition of ffi and it is only e cient when tertiary or stabilised (e.g. benzylic) PPh3 to the reaction mixture, which immediately led to species are generated.19 In our case this fragmentation would a dramatic increase in the process yield (Scheme 2B, entry 6).
Load more

Recommended publications
  • SAFETY DATA SHEET Adamantane According to Regulation (EC) No 1907/2006, Annex II, As Amended
    Revision date: 21/11/2017 Revision: 1 SAFETY DATA SHEET Adamantane According to Regulation (EC) No 1907/2006, Annex II, as amended. Commission Regulation (EU) No 2015/830 of 28 May 2015. SECTION 1: Identification of the substance/mixture and of the company/undertaking 1.1. Product identifier Product name Adamantane Product number FA01417 CAS number 281-23-2 EC number 206-001-4 1.2. Relevant identified uses of the substance or mixture and uses advised against Identified uses Laboratory reagent. Manufacture of substances. Research and development. 1.3. Details of the supplier of the safety data sheet Supplier Carbosynth Ltd 8&9 Old Station Business Park Compton Berkshire RG20 6NE UK +44 1635 578444 +44 1635 579444 [email protected] 1.4. Emergency telephone number Emergency telephone +44 7887 998634 SECTION 2: Hazards identification 2.1. Classification of the substance or mixture Classification (EC 1272/2008) Physical hazards Not Classified Health hazards Skin Irrit. 2 - H315 Eye Irrit. 2 - H319 Environmental hazards Aquatic Acute 1 - H400 Aquatic Chronic 1 - H410 2.2. Label elements EC number 206-001-4 Pictogram Signal word Warning 1/9 Revision date: 21/11/2017 Revision: 1 Adamantane Hazard statements H315 Causes skin irritation. H319 Causes serious eye irritation. H410 Very toxic to aquatic life with long lasting effects. Precautionary statements P264 Wash contaminated skin thoroughly after handling. P280 Wear protective gloves/ protective clothing/ eye protection/ face protection. P302+P352 IF ON SKIN: Wash with plenty of water. P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do.
    [Show full text]
  • Minutes of the IUPAC Chemical Nomenclature and Structure Representation Division (VIII) Committee Meeting Boston, MA, USA, August 18, 2002
    Minutes of the IUPAC Chemical Nomenclature and Structure Representation Division (VIII) Committee Meeting Boston, MA, USA, August 18, 2002 Members Present: Dr Stephen Heller, Prof Herbert Kaesz, Prof Dr Alexander Lawson, Prof G. Jeffrey Leigh, Dr Alan McNaught (President), Dr. Gerard Moss, Prof Bruce Novak, Dr Warren Powell (Secretary), Dr William Town, Dr Antony Williams Members Absent: Dr. Michael Dennis, Prof Michael Hess National representatives Present: Prof Roberto de Barros Faria (Brazil) The second meeting of the Division Committee of the IUPAC Division of Chemical Nomenclature and Structure Representation held in the Great Republic Room of the Westin Hotel in Boston, Massachusetts, USA was convened by President Alan McNaught at 9:00 a.m. on Sunday, August 18, 2002. 1.0 President McNaught welcomed the members to this meeting in Boston and offered a special welcome to the National Representative from Brazil, Prof Roberto de Barros Faria. He also noted that Dr Michael Dennis and Prof Michael Hess were unable to be with us. Each of the attendees introduced himself and provided a brief bit of background information. Housekeeping details regarding breaks and lunch were announced and an invitation to a reception from the U. S. National Committee for IUPAC on Tuesday, August 20 was noted. 2.0 The agenda as circulated was approved with the addition of a report from Dr Moss on the activity on his website. 3.0 The minutes of the Division Committee Meeting in Cambridge, UK, January 25, 2002 as posted on the Webboard (http://www.rsc.org/IUPAC8/attachments/MinutesDivCommJan2002.rtf and http://www.rsc.org/IUPAC8/attachments/MinutesDivCommJan2002.pdf) were approved with the following corrections: 3.1 The name Dr Gerard Moss should be added to the members present listing.
    [Show full text]
  • One-Stage Catalytic Oxidation of Adamantane to Tri-, Tetra-, and Penta-Ols
    catalysts Article One-Stage Catalytic Oxidation of Adamantane to Tri-, Tetra-, and Penta-Ols Igor Yu. Shchapin 1,2,3,*, Dzhamalutdin N. Ramazanov 4, Andrey I. Nekhaev 4, Roman S. Borisov 4, Evgeny A. Buravlev 5 and Anton L. Maximov 4 1 Department of Chemistry, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia 2 Department of High Energy Chemistry and Radioecology, D.I. Mendeleev University of Chemical Technology of Russia, 125047 Moscow, Russia 3 Branch of Joint-Stock Company “United Rocket and Space Corporation”—“Scientific Research Institute of Space Device Engineering”, 111024 Moscow, Russia 4 A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 119991 Moscow, Russia; [email protected] (D.N.R.); [email protected] (A.I.N.); [email protected] (R.S.B.); [email protected] (A.L.M.) 5 Department of Physics and Mathematics, N.I. Pirogov Russian National Research Medical University, 117997 Moscow, Russia; [email protected] * Correspondence: [email protected] Abstract: Tertiary tetraols of adamantane (C10H16, Tricyclo[3.3.1.1(3,7)]decan) have been widely used for the synthesis of highly symmetric compounds with unique physical and chemical properties. The methods for one-stage simultaneously selective, deep, and cheap oxidation of adamantane to tetraols of different structures have not yet been developed. In this research, chemically simple, cheap, and environmentally friendly reagents are used and that is the first step in this direction. The conditions, under which the impact of a hydrogen peroxide water solution on adamantane Citation: Shchapin, I.Yu.; dissolved in acetonitrile results in full conversion of adamantane and formation of a total 72% Ramazanov, D.N.; Nekhaev, A.I.; mixture of its tri-, tetra-, and penta-oxygenated products, predominantly poliols, have been found.
    [Show full text]
  • The Synthesis of Diamond Films on Adamantane-Coated Si Substrate At
    Chemical Engineering Journal 158 (2010) 641–645 Contents lists available at ScienceDirect Chemical Engineering Journal journal homepage: www.elsevier.com/locate/cej Short communication The synthesis of diamond films on adamantane-coated Si substrate at low temperature Rajanish N. Tiwari ∗, Jitendra N. Tiwari, Li Chang ∗ Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan, ROC article info abstract Article history: Diamond films have been synthesized on the adamantane-coated Si (1 0 0) substrate by microwave Received 13 November 2009 plasma chemical vapor deposition from a gaseous mixture of methane and hydrogen gases with a Received in revised form 8 January 2010 growth rate of ∼6.7 nm/min. The substrate temperature was ∼475 ◦C during diamond deposition. The Accepted 11 January 2010 films obtained have good crystallinity that is characterized by scanning electron microscopy and Raman spectrometry. X-ray photoelectron spectroscopy analysis has confirmed that diamond nucleation and Keywords: growth are on SiC rather than clean Si. The possible mechanism of high rate growth diamond films has Diamond been demonstrated. Adamantane MPCVD © 2010 Elsevier B.V. All rights reserved. 1. Introduction hedral and C–C single bond has a length of 1.54 Å. Partial collapse of adamantane molecules is known to yield carbon clusters (CnHx) Recently, the synthesis of diamond at low temperature has where n = 3, 5, 6, 7, 8 and 9 of significant abundance [16].Tothe attracted much attention of materials scientists, owing to its best of our knowledge, this is the first report showing the synthesis wide range of applications in optics, microelectronics, tribological, of diamond films on the adamantane-coated Si (1 0 0) substrate at thermal management, biomedical, DNA-based sensor, and manu- low temperature.
    [Show full text]
  • Safety Data Sheets
    SAFETY DATA SHEETS According to Globally Harmonized System of Classification and Labelling of Chemicals (GHS) - Sixth revised edition Version: 1.0 Creation Date: Feb. 6, 2018 Revision Date: Feb. 6, 2018 1. Identification 1.1 GHS Product identifier Product name Adamantane 1.2 Other means of identification Product number A506396 Other names Adamantane 1.3 Recommended use of the chemical and restrictions on use Identified uses Used for research and development only. Uses advised against no data available 1.4 Supplier's details Company Sangon Biotech (Shanghai) Co., Ltd. Address 698 Xiangmin Road, Songjiang, Shanghai 201611, China Telephone +86-400-821-0268 / +86-800-820-1016 Fax +86-400-821-0268 to 9 1.5 Emergency phone number Emergency phone +86-21-57072055 number Service hours Monday to Friday, 9am-5pm (Standard time zone: UTC/GMT +8 hours). 2. Hazard identification 2.1 Classification of the substance or mixture Acute toxicity - Oral, Category 4 2.2 GHS label elements, including precautionary statements Pictogram(s) Signal word Warning Hazard statement(s) H302 Harmful if swallowed Adamantane Page 1 of 8 Precautionary statement(s) Prevention P264 Wash ... thoroughly after handling. P270 Do not eat, drink or smoke when using this product. Response P301+P312 IF SWALLOWED: Call a POISON CENTER/doctor/…if you feel unwell. P330 Rinse mouth. Storage none Disposal P501 Dispose of contents/container to ... 2.3 Other hazards which do not result in classification no data available 3. Composition/information on ingredients 3.1 Substances Common names and CAS EC Chemical name Concentration synonyms number number 206-001- Tricyclo[3.3.1.13,7]decane Adamantane 281-23-2 ≥99% 4 4.
    [Show full text]
  • Synthesis and Biological Evaluation of 1-(2-(Adamantane-1-Yl)-1H-Indol-5-Yl)-3-Substituted Urea/Thiourea Derivatives As Anticanc
    RSC Advances View Article Online PAPER View Journal | View Issue Synthesis and biological evaluation of 1-(2- (adamantane-1-yl)-1H-indol-5-yl)-3-substituted Cite this: RSC Adv.,2017,7, 51640 urea/thiourea derivatives as anticancer agents† Hongyu Hu,‡ab Chunrong Lin,‡a Mingtao Ao,‡a Yufen Ji,a Bowen Tang,a Xiaoxiao Zhou,a Meijuan Fang, *a Jinzhang Zeng*a and Zhen Wu*a The indole ring, adamantane, and urea groups are important components of bioactive molecules. The orphan nuclear receptor Nur77 as a unique transcription factor encoded by an immediate early gene is a potential therapeutic target for cancer treatment. We synthesized a series of 1-(2-(adamantane-1-yl)- 1H-indol-5-yl)-3-substituted urea/thiourea derivatives and identified which of these potential anticancer candidates could modulate the expression and activity of Nur77. The synthesized compounds were initially evaluated for their anti-proliferative activity against H460 lung cancer cells, HepG2 liver cancer cells, and MCF-7 breast cancer cells. Major compounds were found to be active against these tested Creative Commons Attribution-NonCommercial 3.0 Unported Licence. cancer cell lines. The compounds with IC50 values down to 20 mM exhibited selective cytotoxicity effects on the human lung cancer cell line (H460) and the normal lung cell line (MCR-5). Compounds 7n, 7s, and 7w induced Nur77-expression in a time- and dose-dependent manner in H460 cells. Compounds 7n and 7s strongly induced Parp cleavage in H460 cells, but 7w resulted in a slight induction of Received 24th July 2017 apoptosis. The apoptotic effect of 7s was largely inhibited when the Nur77 was knocked down by shRNA.
    [Show full text]
  • Self-Assembly of Nanoscopic Coordination Cages of D3h Symmetry Christopher J
    Self-assembly of nanoscopic coordination cages of D3h symmetry Christopher J. Kuehl*, Yury K. Kryschenko*, Ukkirampandian Radhakrishnan*, S. Russell Seidel*, Songping D. Huang†, and Peter J. Stang*‡ *Department of Chemistry, University of Utah, Salt Lake City, UT 84112; and †Department of Chemistry, Kent State University, Kent, OH 44242 Contributed by Peter J. Stang, October 11, 2001 A family of nanoscale-sized supramolecular cage compounds with a tures of variable size and functionality, in high yield, and without trigonal prismatic framework was prepared by means of spontaneous the use of templates. Specifically, the modular self-assembly of self-assembly from the combination of a predesigned molecular ‘‘clip’’ a new family of metalla-bicyclic structures (3a–3c), directed by with tritopic pyridyl subunits. As confirmed by x-ray crystallography, a molecular ‘‘clip’’ (1) as a preconstructed shape-defining unit, ,the smallest structure of the reported series is Ϸ1 ؋ 2nmand is described. The structure and properties of these nanoscopic possesses a nitrate anion incarcerated inside its molecular cavity. The macrocyclic species have been studied by electrospray ioniza- largest structure has dimensions of Ϸ 1 ؋ 4 nm. tion (ESI)-mass spectrometry, multinuclear NMR, and x-ray crystallography. he formation of discrete supramolecular entities driven and Experimental Section Theld together by metal coordination is an intense new area of investigation at the forefront of supramolecular chemistry General Methods. Building unit 2a (47) was synthesized by a (1–10). Because self-assembly is guided by the chemical infor- published method and 2b and 2c were prepared in an analogous mation encoded into the molecular subunits, diverse structures manner.
    [Show full text]
  • Impact of H2O2 on the Lactic and Formic Acid Degradation in Presence of Tio2 Rutile and Anatase Phases Under UV and Visible Light
    catalysts Article Impact of H2O2 on the Lactic and Formic Acid Degradation in Presence of TiO2 Rutile and Anatase Phases under UV and Visible Light Annika Holm 1,2, Marwa Hamandi 1, Karima Sahel 3, Frederic Dappozze 1 and Chantal Guillard 1,* 1 University of Lyon, Université Claude Bernard Lyon 1, 2 avenue Albert Einstein, F-69626 Villeurbanne, France; [email protected] (A.H.); [email protected] (M.H.); [email protected] (F.D.) 2 Chemistry Department, Sonoma State University (SSU), 1801 East Cotative Ave, Rohnert Park, CA 94928, USA 3 Laboratoire des Eco-Matériaux Fonctionnels et Nanostructurés, Faculté de Chimie, Département Génie des Matériaux, Université des Sciences et de la Technologie d’Oran (USTO), Bir El Djir 3100, Algeria; [email protected] * Correspondence: [email protected]; Tel.: +33-472-445-316 Received: 27 August 2020; Accepted: 21 September 2020; Published: 1 October 2020 Abstract: The degradation rates of formic acid and lactic acid in the presence and absence of H2O2 were studied, utilizing several TiO2 catalysts: PC105 (100% anatase), MPT 625 (100% rutile), and P25 (80% anatase/20% rutile), and the results were discussed with regards to the current literature. The impact of hydrogen peroxide on the photocatalytic efficiency of eleven TiO2 samples was then determined, using commercial anatase structures (PC105, PC500, UV100), commercial mixed anatase/rutile (P25 and P90), and six rutile (two commercial samples: MPT 625 and C-R160, and four home-made rutile samples were synthesized by TiCl4 hydrolysis). The effect of catalyst surface area and TiO2 phase on the degradation rate of lactic acid (LA) and the decomposition of H2O2 was studied and discussed in regard to the active species generated.
    [Show full text]
  • Ge4se10] Anions
    2914 Chem. Mater. 2000, 12, 2914-2923 Surfactant-Templated Inorganic Lamellar and Non-Lamellar Hybrid Phases Containing Adamantane 4- [Ge4Se10] Anions Michael Wachhold and Mercouri G. Kanatzidis* Department of Chemistry and Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824 Received February 8, 2000. Revised Manuscript Received May 22, 2000 The metathesis reaction of K4Ge4Se10 with various alkyl tri- and dimethylammonium halides [CnH2n+1N(CH3)3-mHm]X (n ) 8, 9, 10, 12, 14, 16, 18; m ) 0, 1; X ) Cl, Br) led to several new surfactant-inorganic template phases containing selenogermanate adamantane 4- units [Ge4Se10]. The crystal structures of phases with shorter alkylammonium chains (n ) 8 and 9) have been determined by single-crystal X-ray crystallography; octyltrimethyl- ammonium decaselenotetragermanate, [n-C8H17N(CH3)3]4Ge4Se10 (C8-GeSe), monoclinic, space group C2/c, Z ) 4, a ) 34.2324(9) Å, b ) 10.9213(3) Å, c ) 19.2700(5) Å, â ) 104.567°; nonyltrimethylammonium decaselenotetragermanate [n-C9H19N(CH3)3]4Ge4Se10 (C9-GeSe), triclinic, space group P1h, Z ) 2, a ) 10.7799(2) Å, b ) 18.1172(3) Å, c ) 19.0075(1) Å, R) 91,881(1)°, â ) 90.017(1)°, γ ) 98.767(1)°; octyldimethylammonium decaselenotetragermanate [n-C8H17N(CH3)2H]4Ge4Se10 (ODA-GeSe) tetragonal, space group I1/a, Z ) 4, a ) 18.6462- 4- (1) Å, c ) 19.2038(1) Å. C8-GeSe and C9-GeSe are composed of parallel layers of [Ge4Se10] anions in a pseudohexagonal arrangement, separated by the charge-balancing surfactant cations. While C9-GeSe contains bilayers of parallel interdigitating surfactant hydrocarbon chains, the shorter chains in C8-GeSe show a crisscross-like arrangement.
    [Show full text]
  • The History of Ozone. Vi. Ozone on Silica Gel (“Dry Ozone”) (1)
    68 Bull. Hist. Chem., VOLUME 33, Number 2 (2008) THE HISTORY OF OZONE. VI. OZONE ON SILICA GEL (“DRY OZONE”) (1) Mordecai B. Rubin, Technion-Israel Institute of Technology Introduction partial pressure. As can be seen in Figure 2, adsorption increased mark- As part of a general study of edly with decreasing temperature, the the interaction between gases significance of temperatures below the and solids in the laboratory of boiling point of ozone (-112o C) is not Alfred Magnus (Fig. 1) at the clear. The measurements were made University of Frankfurt, Magnus by passing ozone-enriched oxygen and Grähling (2) reported the (ca 2% ozone) from a silent discharge adsorption of ozone on silica gel apparatus through a tube packed with in 1929. These measurements silica gel until compositions of the were complicated by the thermal entrance and exit gases were identi- instability of ozone, which, as cal. The ozone was then desorbed and shown by Magnus and Grähling, analyzed iodimetrically. was further catalyzed by silica gel. A second problem was the low More recently Atyaksheva and concentration of ozone in oxy- co-workers (4) have studied the gen obtained from conventional adsorption of ozone on silica gel in ozone generators. Nonetheless, considerable detail. Bulanin et al. (5) Figure 1. Alfred Magnus, Un. of Frankfurt, reported that the IR spectrum of differ- Magnus and Grähling found that 1880-1960. considerable amounts of ozone ent isotopic ozone species on silica gel could be adsorbed on silica gel at low temperatures where at 80 K exhibited hydrogen bonding of decomposition was not a problem.
    [Show full text]
  • Exploring Palladium-Mediated 11C/12C-Carbonylation Reactions
    Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Pharmacy 241 Exploring Palladium-Mediated 11C/12C-Carbonylation Reactions PET Tracer Development Targeting the Vesicular Acetylcholine Transporter SARA ROSLIN ACTA UNIVERSITATIS UPSALIENSIS ISSN 1651-6192 ISBN 978-91-513-0136-5 UPPSALA urn:nbn:se:uu:diva-332359 2017 Dissertation presented at Uppsala University to be publicly examined in Hall B:21, BMC, Husargatan 3, Uppsala, Friday, 15 December 2017 at 09:15 for the degree of Doctor of Philosophy (Faculty of Pharmacy). The examination will be conducted in English. Faculty examiner: Ph.D. Victor Pike (National Institute of Mental Health, Molecular Imaging Branch). Abstract Roslin, S. 2017. Exploring Palladium-Mediated 11C/12C-Carbonylation Reactions. PET Tracer Development Targeting the Vesicular Acetylcholine Transporter. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Pharmacy 241. 99 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-0136-5. The work presented herein describes the utilization and exploration of palladium-mediated incorporations of carbon monoxide and/or [11C]carbon monoxide into compounds and structural motifs with biological relevance. The first part of the thesis describes the design, synthesis and 11C-labeling of prospective PET tracers for the vesicular acetylcholine transporter (VAChT), a target affected in several neurodegenerative diseases. Different parts of the benzovesamicol scaffold were modified in papers I and II to probe the binding to VAChT. The key motif was an amide functional group, which enabled the use of palladium-mediated 11C/12C-carbonylations to synthesize and evaluate two different sets of structurally related ligands. The second part of the thesis describes the exploration of different aspects of palladium- mediated 11C/12C-carbonylation reactions.
    [Show full text]
  • Cyclodextrin and Bio-Conjugatable Adamantane Derivatives
    molecules Communication Structural Insights into the Host–Guest Complexation between β-Cyclodextrin and Bio-Conjugatable Adamantane Derivatives Jian-Wei Wang 1, Ka-Xi Yu 1, Xin-Yuan Ji 1, Hongzhen Bai 1, Wen-Hua Zhang 2 , Xiurong Hu 1,* and Guping Tang 1,* 1 Department of Chemistry, Zhejiang University, Hangzhou 310028, China; [email protected] (J.-W.W.); [email protected] (K.-X.Y.); [email protected] (X.-Y.J.); [email protected] (H.B.) 2 Department of Materials, Chemistry and Chemical Engineering, Soochow University, Suzhou 215123, China; [email protected] * Correspondence: [email protected] (X.H.); [email protected] (G.T.) Abstract: Understanding the host–guest chemistry of α-/β-/γ- cyclodextrins (CDs) and a wide range of organic species are fundamentally attractive, and are finding broad contemporary applications toward developing efficient drug delivery systems. With the widely used β-CD as the host, we herein demonstrate that its inclusion behaviors toward an array of six simple and bio-conjugatable adaman- tane derivatives, namely, 1-adamantanol (adm-1-OH), 2-adamantanol (adm-2-OH), adamantan-1- amine (adm-1-NH2), 1-adamantanecarboxylic acid (adm-1-COOH), 1,3-adamantanedicarboxylic acid (adm-1,3-diCOOH), and 2-[3-(carboxymethyl)-1-adamantyl]acetic acid (adm-1,3-diCH2COOH), offer inclusion adducts with diverse adamantane-to-CD ratios and spatial guest locations. In all six cases, β-CD crystallizes as a pair supported by face-to-face hydrogen bonding between hydroxyl Citation: Wang, J.-W.; Yu, K.-X.; Ji, groups on C2 and C3 and their adjacent equivalents, giving rise to a truncated-cone-shaped cavity X.-Y.; Bai, H.; Zhang, W.-H.; Hu, X.; to accommodate one, two, or three adamantane derivatives.
    [Show full text]