Carboligation Using the Aldol Reaction
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
556 Florida Entomologist 81(4) December, 1998
556 Florida Entomologist 81(4) December, 1998 Nontarget Hymenoptera have been collected in bucket traps placed in field crops which were baited for several different noctuid species (Adams et al. 1989, Mitchell et al. 1989, Gauthier et al. 1991), however, this is the first report for collection of L. bicolor. SUMMARY Larra bicolor was collected as a nontarget species in white bucket traps baited with sex pheromones and the floral attractant phenylacetaldehyde in an agricultural area in northwestern Alachua County, Florida. The first wasp was collected in mid- June, but larger numbers of wasps were collected in late September and early Octo- ber. More wasps were collected in traps that had phenylacetaldehyde as a lure. This collection method may aid researchers in determining the dispersal and effectiveness of this natural enemy of Scapteriscus mole crickets. REFERENCES CITED ADAMS, R. G., K. D. MURRAY, AND L. M. LOS. 1989. Effectiveness and selectivity of sex pheromone lures and traps for monitoring fall armyworm (Lepidoptera: Noctu- idae) adults in Connecticut sweet corn. J. Econ. Entomol. 82: 285-290. FRANK, J. H., J. P. PARKMAN, AND F. D. BENNETT. 1995. Larra bicolor (Hymenoptera: Sphecidae), a biological control agent of Scapteriscus mole crickets (Ortho- ptera: Gryllotalpidae), established in northern Florida. Fla. Entomol. 78: 619- 623. GAUTHIER, N. L., P. A. LOGAN, L. A. TEWKSBURY, C. F. HOLLINGSWORTH, D. C. WEBER, AND R. G. ADAMS. 1991. Field bioassay of pheromone lures and trap designs for monitoring adult corn earworm (Lepidoptera: Noctuidae) in sweet corn in southern New England. J. Econ. Entomol. 84: 1833-1836. MITCHELL, E. -
3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters
www.nature.com/scientificreports OPEN Monitoring of heat‑induced carcinogenic compounds (3‑monochloropropane‑1,2‑diol esters and glycidyl esters) in fries Yu Hua Wong1, Kok Ming Goh1,2, Kar Lin Nyam2, Ling Zhi Cheong3, Yong Wang4, Imededdine Arbi Nehdi5,6, Lamjed Mansour7 & Chin Ping Tan1* 3‑Monochloropropane‑1,2‑diol (3‑MCPD) esters and glycidyl esters (GE) are heat‑induced contaminants which form during oil refning process, particularly at the high temperature deodorization stage. It is worth to investigate the content of 3‑MCPD and GE in fries which also involved high temperature. The content of 3‑MCPD esters and GE were monitored in fries. The factors that been chosen were temperature and duration of frying, and diferent concentration of salt (NaCl). The results in our study showed that the efect was in the order of concentration of sodium chloride < frying duration < frying temperature. The content of 3‑MCPD esters was signifcantly increased whereas GE was signifcantly decreased, when prolong the frying duration. A high temperature results in a high 3‑MCPD ester level but a low GE level in fries. The present of salt had contributed signifcant infuence to the generation of 3‑MCPD. The soaking of potato chips in salt showed no signifcant efect on the level of GE during the frying. The oil oxidation tests showed that all the fries were below the safety limit. Hence, the frying cycle, temperature and the added salt to carbohydrate‑based food during frying should be monitored. Deep-fat frying is commonly being used to process food. During the process, heat transfer between the fried food and oil is occurs. -
Zn-Nx Sites on N-Doped Carbon for Aerobic Oxidative Cleavage
ARTICLE https://doi.org/10.1038/s41467-021-25118-0 OPEN Zn-Nx sites on N-doped carbon for aerobic oxidative cleavage and esterification of C(CO)-C bonds ✉ ✉ Chao Xie1, Longfei Lin 2, Liang Huang 3, Zixin Wang1, Zhiwei Jiang 1, Zehui Zhang1 & Buxing Han 2 Selective cleavage of C-C bonds is very important in organic chemistry, but remains chal- lenging because of their inert chemical nature. Herein, we report that Zn/NC-X catalysts, in 1234567890():,; which Zn2+ coordinate with N species on microporous N-doped carbon (NC) and X denotes the pyrolysis temperature, can effectively catalyze aerobic oxidative cleavage of C(CO)-C bonds and quantitatively convert acetophenone to methyl benzoate with a yield of 99% at 100 °C. The Zn/NC-950 can be applied for a wide scope of acetophenone derivatives as well as more challenging alkyl ketones. Detail mechanistic investigations reveal that the catalytic performance of Zn/NC-950 can be attributed to the coordination between Zn2+ and N species to change the electronic state of the metal, synergetic effect of the Zn single sites with their surrounding N atoms, as well as the microporous structure with the high surface area and structural defects of the NC. 1 Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, South- Central University for Nationalities, Wuhan, China. 2 Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China. 3 The State Key Laboratory of Refractories and Metallurgy, ✉ Wuhan University of Science and Technology, Wuhan, China. -
Synthesis and Consecutive Reactions of Α-Azido Ketones: a Review
Molecules 2015, 20, 14699-14745; doi:10.3390/molecules200814699 OPEN ACCESS molecules ISSN 1420-3049 www.mdpi.com/journal/molecules Review Synthesis and Consecutive Reactions of α-Azido Ketones: A Review Sadia Faiz 1,†, Ameer Fawad Zahoor 1,*, Nasir Rasool 1,†, Muhammad Yousaf 1,†, Asim Mansha 1,†, Muhammad Zia-Ul-Haq 2,† and Hawa Z. E. Jaafar 3,* 1 Department of Chemistry, Government College University Faisalabad, Faisalabad-38000, Pakistan, E-Mails: [email protected] (S.F.); [email protected] (N.R.); [email protected] (M.Y.); [email protected] (A.M.) 2 Office of Research, Innovation and Commercialization, Lahore College for Women University, Lahore-54600, Pakistan; E-Mail: [email protected] 3 Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, Serdang-43400, Selangor, Malaysia † These authors contributed equally to this work. * Authors to whom correspondence should be addressed; E-Mails: [email protected] (A.F.Z.); [email protected] (H.Z.E.J.); Tel.: +92-333-6729186 (A.F.Z.); Fax: +92-41-9201032 (A.F.Z.). Academic Editors: Richard A. Bunce, Philippe Belmont and Wim Dehaen Received: 20 April 2015 / Accepted: 3 June 2015 / Published: 13 August 2015 Abstract: This review paper covers the major synthetic approaches attempted towards the synthesis of α-azido ketones, as well as the synthetic applications/consecutive reactions of α-azido ketones. Keywords: α-azido ketones; synthetic applications; heterocycles; click reactions; drugs; azides 1. Introduction α-Azido ketones are very versatile and valuable synthetic intermediates, known for their wide variety of applications, such as in amine, imine, oxazole, pyrazole, triazole, pyrimidine, pyrazine, and amide alkaloid formation, etc. -
Than Was the Monoleucyl Ester of Cis-Cyclopentane-1,2-Diol
SOME OBSERVATIONS ON THE MECHANISM OF THE ACYLATION PROCESS IN PROTEIN SYNTHESIS* BY BEVERLY E. GRIFFIN AND C. B. REESE UNIVERSITY CHEMICAL LABORATORY, CAMBRIDGE, ENGLAND Communicated by Lord Todd, January 2, 1964 During recent years much attention has been given to the mechanism of synthesis of proteins in biological systems.' Although the process is by no means fully understood, some of the steps involved appear to be well established.2-4 Before amino acids can be incorporated into polypeptide chains they must first be "activated." The "activation" process involves ribonucleic acids of comparatively low molecular weight, known as "transfer" or "soluble" ribonucleic acids (sRNA), adenosine-5' triphosphate (ATP) as an energy source, and a specific enzyme for each amino acid. In the first step of the "activation" process, the amino acid reacts with ATP to form a mixed anhydride with adenosine-5' phosphate (AMP) releasing inorganic pyrophosphate; this mixed anhydride then acylates a specific sRNA on its terminal nucleoside (adenosine) residue to yield a 2' (or 3')-aminoacyl ester-the "activated" amino-acid. These processes are reversible. ATP + amino acid aminoacyl-AMP + pyrophosphate (1) sRNA + aminoacyl-AMP aminoacyl-sRNA + AMP (2) Beyond this point our knowledge of the process of polypeptide synthesis is less certain. The "activated" amino acids are believed to be transferred to the ribo- somes-the site of assembly of polypeptide chains-and then the amino acids become linked together in a genetically controlled order to synthesize a specific protein.5 Although there is as yet no definite evidence regarding this final step, it is frequently assumed that it involves a simple acylation as indicated in step (3). -
Chemical and Photochemical Studies of Unsaturated Cyclooctane Derivatives Thomas Kenneth Hall Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1965 Chemical and photochemical studies of unsaturated cyclooctane derivatives Thomas Kenneth Hall Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Organic Chemistry Commons Recommended Citation Hall, Thomas Kenneth, "Chemical and photochemical studies of unsaturated cyclooctane derivatives " (1965). Retrospective Theses and Dissertations. 3297. https://lib.dr.iastate.edu/rtd/3297 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. This dissertation has been microiihned exactly as received 66—2988 HALL, Thomas Kenneth, 1936— CHEMICAL AND PHOTOCHEMICAL STUDIES OF UNSATURATED CYCLOOCTANE DERIVATIVES. Iowa State University of Science and Technology Ph.D., 1965 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan CHEMICAL AND PHOTOCHEMICAL STUDIES OF UNSATURATED CYCLOOCTANE DERIVATIVES by Thomas Kenneth Hall A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject; Organic Chemistry Approved: Signature was redacted for privacy. Signature was redacted for privacy. Head -
Aldehydes Can React with Alcohols to Form Hemiacetals
340 14 . Nucleophilic substitution at C=O with loss of carbonyl oxygen You have, in fact, already met some reactions in which the carbonyl oxygen atom can be lost, but you probably didn’t notice at the time. The equilibrium between an aldehyde or ketone and its hydrate (p. 000) is one such reaction. O HO OH H2O + R1 R2 R1 R2 When the hydrate reverts to starting materials, either of its two oxygen atoms must leave: one OPh came from the water and one from the carbonyl group, so 50% of the time the oxygen atom that belonged to the carbonyl group will be lost. Usually, this is of no consequence, but it can be useful. O For example, in 1968 some chemists studying the reactions that take place inside mass spectrometers needed to label the carbonyl oxygen atom of this ketone with the isotope 18 O. 16 18 By stirring the ‘normal’ O compound with a large excess of isotopically labelled water, H 2 O, for a few hours in the presence of a drop of acid they were able to make the required labelled com- í In Chapter 13 we saw this way of pound. Without the acid catalyst, the exchange is very slow. Acid catalysis speeds the reaction up by making a reaction go faster by raising making the carbonyl group more electrophilic so that equilibrium is reached more quickly. The the energy of the starting material. We 18 also saw that the position of an equilibrium is controlled by mass action— O is in large excess. -
3 Alkenes from 1,2-Diols
REVISTA BOLIVIANA DE QUÍMICA (Rev.Bol.Quim.) Vol. 32, No.5, pp. 121-125, Nov./Dic. 2015 Bolivian Journal of Chemistry 32(5) 121-125, Nov./Dec. 2015 Received 12 14 2015 Accepted 12 23 2015 Published 12 30 2015 Bravo et Vila . STEREOSPECIFIC SYNTHESIS OF ALKENES FROM 1,2-DIOLS; MECHANISTIC VIEWS; THE ORGANIC CHEMISTRY NOTEBOOK SERIES, A DIDACTICAL APPROACH, Nº 8 José A. Bravo 1,*, José L. Vila 2 1Department of Chemistry, Laboratorio de Fitoquímica, Instituto de Investigaciones en Productos Naturales IIPN, Universidad Mayor de San Andrés UMSA, P.O. Box 303, Calle Andrés Bello s/n, Ciudad Universitaria Cota Cota, Phone 59122792238, La Paz, Bolivia, [email protected] 2Department of Chemistry, Laboratorio de Síntesis y Hemisíntesis, Instituto de Investigaciones en Productos Naturales IIPN, Universidad Mayor de San Andrés UMSA, P.O. Box 303, Calle Andrés Bello s/n, Ciudad Universitaria Cota Cota, Phone 59122795878, La Paz, Bolivia, [email protected] Keywords: Organic Chemistry, Alkenes, 1,2-diols, Stereospecific synthesis, Mechanisms of Reactions, W. Carruthers. ABSTRACT This is the eighth chapter in the series: “The Organic Chemistry Notebook Series, a Didactical Approach”. The aim of this series of studies is to help students to have a graphical view of organic synthesis reactions of diverse nature. Here we discuss, from a mechanistic stand point, some methods for the stereospecific synthesis of alkenes from 1,2-diols. One of the best ones utilizes as precursors, the cyclic thionocarbonates obtained from the diol with thiophosgene. We describe by mechanisms, the use of 1,3-dimethyl-2-phenyl-1,3,2-diazophospholidine as an alternative for the decomposition of thionocarbonates into alkenes. -
Formation of Phenylacetic Acid and Benzaldehyde by Degradation Of
Food Chemistry: X 2 (2019) 100037 Contents lists available at ScienceDirect Food Chemistry: X journal homepage: www.journals.elsevier.com/food-chemistry-x Formation of phenylacetic acid and benzaldehyde by degradation of phenylalanine in the presence of lipid hydroperoxides: New routes in the amino acid degradation pathways initiated by lipid oxidation products ⁎ Francisco J. Hidalgo, Rosario Zamora Instituto de la Grasa, Consejo Superior de Investigaciones Científicas, Carretera de Utrera km 1, Campus Universitario – Edificio 46, 41013 Seville, Spain ARTICLE INFO ABSTRACT Chemical compounds studied in this article: Lipid oxidation is a main source of reactive carbonyls, and these compounds have been shown both to degrade Benzaldehyde (PubChem ID: 240) amino acids by carbonyl-amine reactions and to produce important food flavors. However, reactive carbonyls 4-Oxo-2-nonenal (PubChem ID: 6445537) are not the only products of the lipid oxidation pathway. Lipid oxidation also produces free radicals. 13-Hydroperoxy-9Z,11E-octadecadienoic acid Nevertheless, the contribution of these lipid radicals to the production of food flavors by degradation of amino (PubChem ID: 5280720) acid derivatives is mostly unknown. In an attempt to investigate new routes of flavor formation, this study Phenylacetaldehyde (PubChem ID: 998) describes the degradation of phenylalanine, phenylpyruvic acid, phenylacetaldehyde, and β-phenylethylamine Phenylacetic acid (PubChem ID: 999) β-Phenylethylamine (PubChem ID: 1001) in the presence of the 13-hydroperoxide of linoleic acid, 4-oxononenal (a reactive carbonyl derived from this Phenylalanine (PubChem ID: 6140) hydroperoxide), and the mixture of both of them. The obtained results show the formation of phenylacetic acid Phenylpyruvic acid (PubChem ID: 997) and benzaldehyde in these reactions as a consequence of the combined action of carbonyl-amine and free radical reactions for amino acid degradation. -
Metabolic Engineering of Escherichia Coli to High Efficient Synthesis
Zhang et al. AMB Expr (2017) 7:105 DOI 10.1186/s13568-017-0407-0 ORIGINAL ARTICLE Open Access Metabolic engineering of Escherichia coli to high efcient synthesis phenylacetic acid from phenylalanine Lihua Zhang1,2, Qian Liu1,2, Hong Pan2*, Xun Li2 and Daoyi Guo1,2* Abstract Phenylacetic acid (PAA) is a fne chemical with a high industrial demand for its widespread uses. Whereas, microor- ganic synthesis of PAA is impeded by the formation of by-product phenethyl alcohol due to quick, endogenous, and superfuous conversion of aldehydes to their corresponding alcohols, which resulted in less conversation of PAA from aldehydes. In this study, an Escherichia coli K-12 MG1655 strain with reduced aromatic aldehyde reduction (RARE) that does duty for a platform for aromatic aldehyde biosynthesis was used to prompt more PAA biosynthesis. We establish a microbial biosynthetic pathway for PAA production from the simple substrate phenylalanine in E. coli with heterolo- gous coexpression of aminotransferase (ARO8), keto acid decarboxylase (KDC) and aldehyde dehydrogenase H (AldH) gene. It was found that PAA transformation yield was up to ~94% from phenylalanine in E. coli and there was no by-product phenethyl alcohol was detected. Our results reveal the high efciency of the RARE strain for production of PAA and indicate the potential industrial applicability of this microbial platform for PAA biosynthesis. Keywords: Metabolic engineering, Phenylacetic acid, Phenylalanine, Phenylacetaldehyde Introduction utilizing a nitrile hydratase and an amidase of Rhodococ- Phenylacetic acid (PAA) has received much attention on cus equi TG328 (Gilligan et al. 1993) or an arylacetoni- account of its extensive applications, which ofer the huge trilase from Pseudomonas fuorescens EBC191 (Sosedov demand. -
Chapter 19 the Chemistry of Aldehydes and Ketones. Addition Reactions
Instructor Supplemental Solutions to Problems © 2010 Roberts and Company Publishers Chapter 19 The Chemistry of Aldehydes and Ketones. Addition Reactions Solutions to In-Text Problems 19.1 (b) (d) (e) (g) 19.2 (a) 2-Propanone (d) (E)-3-Ethoxy-2-propenal (f) 4,4-Dimethyl-2,5-cyclohexadienone 19.3 (b) 2-Cyclohexenone has a lower carbonyl stretching frequency because its two double bonds are conjugated. 19.4 (b) The compound is 2-butanone: (c) The high frequency of the carbonyl absorption suggests a strained ring. (See Eq. 19.4, text p. 897.) In fact, cyclobutanone matches the IR stretching frequency perfectly and the NMR fits as well: 19.6 The structure and CMR assignments of 2-ethylbutanal are shown below. The two methyl groups are chemically equivalent, and the two methylene groups are chemically equivalent; all carbons with different CMR chemical shifts are chemically nonequivalent. INSTRUCTOR SUPPLEMENTAL SOLUTIONS TO PROBLEMS • CHAPTER 19 2 19.7 (a) The double bonds in 2-cyclohexenone are conjugated, but the double bonds in 3-cyclohexenone are not. Consequently, 2-cyclohexenone has the UV spectrum with the greater lmax. 19.9 Compound A, vanillin, should have a p T p* absorption at a greater lmax when dissolved in NaOH solution because the resulting phenolate can delocalize into the carboxaldehyde group; the resulting phenolate from compound B, isovanillin, on the other hand, can only delocalize in the aromatic ring. 19.11 The mass spectrum of 2-heptanone should have major peaks at m/z = 43 (from a-cleavage), 71 (from inductive cleavage), and 58 (from McLafferty rearrangement). -
Review: Synthetic Methods for Amphetamine
Review: Synthetic Methods for Amphetamine A. Allen1 and R. Ely2 1Array BioPharma Inc., Boulder, Colorado 80503 2Drug Enforcement Administration, San Francisco, CA Abstract: This review focuses on synthesis of amphetamine. The chemistry of these methods will be discussed, referenced and precursors highlighted. This review covers the period 1985 to 2009 with emphasis on stereoselective synthesis, classical non-chiral synthesis and bio-enzymatic reactions. The review is directed to the Forensic Community and thus highlights precursors, reagents, stereochemistry, type and name reactions. The article attempts to present, as best as possible, a list of references covering amphetamine synthesis from 1900 -2009. Although this is the same fundamental ground as the recent publication by K. Norman; “Clandestine Laboratory Investigating Chemist Association” 19, 3(2009)2-39, this current review offers another perspective. Keywords: Review, Stereoselective, Amphetamine, Syntheses, references, Introduction: It has been 20 years since our last review of the synthetic literature for the manufacture of amphetamine and methamphetamine. Much has changed in the world of organic transformation in this time period. Chiral (stereoselective) synthetic reactions have moved to the forefront of organic transformations and these stereoselective reactions, as well as regio-reactions and biotransformations will be the focus of this review. Within the synthesis of amphetamine, these stereoselective transformations have taken the form of organometallic reactions, enzymatic reactions, ring openings, - aminooxylations, alkylations and amination reactions. The earlier review (J. Forensic Sci. Int. 42(1989)183-189) addressed for the most part, the ―reductive‖ synthetic methods leading to this drug of abuse. It could be said that the earlier review dealt with ―classical organic transformations,‖ roughly covering the period from 1900-1985.