DOCSLIB.ORG

Aldehydes and Ketones 20 20.1 Introduction to Aldehydes and Ketones DID YOU EVER WONDER

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Aldehydes and Ketones 20 20.1 Introduction to Aldehydes and Ketones DID YOU EVER WONDER Aldehydes and Ketones 20 20.1 Introduction to Aldehydes and Ketones DID YOU EVER WONDER... 20.2 Nomenclature why beta-carotene, which makes carrots 20.3 Preparing Aldehydes and orange, is reportedly good for your eyes? Ketones: A Review 20.4 Introduction to Nucleophilic Addition Reactions his chapter will explore the reactivity of aldehydes and ketones. 20.5 Oxygen Nucleophiles TSpecifically, we will see that a wide variety of nucleophiles will 20.6 Nitrogen Nucleophiles react with aldehydes and ketones. Many of these reactions are com- 20.7 Mechanism Strategies mon in biological pathways, including the role that beta-carotene 20.8 Sulfur Nucleophiles plays in promoting healthy vision. As we will see several times in 20.9 Hydrogen Nucleophiles this chapter, the reactions of aldehydes and ketones are also cleverly 20.10 Carbon Nucleophiles exploited in the design of drugs. The reactions and principles out- 20.11 Baeyer-Villiger Oxidation of lined in this chapter are central to the study of organic chemistry and Aldehydes and Ketones will be used as guiding principles throughout the remaining chapters 20.12 Synthesis Strategies of this textbook. 20.13 Spectroscopic Analysis of Aldehydes and Ketones klein_c20_001-056v1.4.indd 1 30/04/10 16.46 2 CHAPTER 20 Aldehydes and Ketones DO YOU REMEMBER? Before you go on, be sure you understand the following topics. If necessary, review the suggested sections to prepare for this chapter: UÊ À}>À`ÊÀi>}iÌÃÊ­-iVÌʣΰȮÊÊ UÊ ,iÌÀÃÞÌ iÌVÊ>>ÞÃÃÊ­-iVÌʣӰή UÊ "Ý`>ÌÊvÊ>V ÃÊ­-iVÌʣΰ£ä® 6ÃÌÊÜÜÜ°ÜiÞ«ÕðVÊÌÊV iVÊÞÕÀÊÕ`iÀÃÌ>`}Ê>`ÊvÀÊÛ>Õ>LiÊ«À>VÌVi° 20.1 Introduction to Aldehydes and Ketones Aldehydes (RCHO) and ketones (R2CO) are similar in structure in that both classes of com- pounds possess a C5O bond, called a carbonyl group: Carbonyl Group O O RH RR An aldehyde A ketone The carbonyl group of an aldehyde is flanked by one carbon atom and one hydrogen atom, while the carbonyl group of a ketone is flanked by two carbon atoms. Aldehydes and ketones are responsible for many flavors and odors that you will readily recognize: H CO O O 3 O O H H HO H Vanillin Cinnamaldehyde (R)-Carvone Benzaldehyde (Vanilla flavor) (Cinnamon flavor) (Spearmint flavor) (Almond flavor) Many important biological compounds also exhibit the carbonyl moiety, including progester- one and testosterone, the female and male sex hormones. O OH H H H H H H O O Progesterone Testosterone Simple aldehydes and ketones are industrially important; for example: O O HH H3C CH3 Formaldehyde Acetone Acetone is used as a solvent and is commonly found in nail polish remover, while formaldehyde is used as a preservative in some vaccine formulations. Aldehydes and ketones are also used as build- ing blocks in the syntheses of commercially important compounds, including pharmaceuticals and polymers. Compounds containing a carbonyl group react with a large variety of nucleophiles, affording a wide range of possible products. Due to the versatile reactivity of the carbonyl group, aldehydes and ketones occupy a central role in organic chemistry. klein_c20_001-056v1.4.indd 2 30/04/10 16.46 20.2 Nomenclature 3 20.2 Nomenclature Nomenclature of Aldehydes Recall that four discrete steps are required to name most classes of organic compounds (as we saw with alkanes, alkenes, alkynes, and alcohols): 1. Identify and name the parent. 2. Identify and name the substituents. 3. Assign a locant to each substituent. 4. Assemble the substituents alphabetically. Aldehydes are also named using the same four-step procedure. When applying this procedure for naming aldehydes, the following guidelines should be followed: When naming the parent, the suffix “-al” indicates the presence of an aldehyde group: O H Butane Butanal When choosing the parent of an aldehyde, identify the longest chain that includes the carbon atom of the aldehydic group: The parent must include HO this carbon atom Parent=Octane Parent=Hexanal When numbering the parent chain of an aldehyde, the aldehydic carbon is assigned num- ber 1, despite the presence of alkyl substituents, U bonds, or hydroxyl groups: Correct Incorrect 24 6 64 2 H 135 7 H 753 1 O OH O OH It is not necessary to include the locant in the name, because it is understood that the aldehydic carbon is the number 1 position. As with all compounds, when a chirality center is present, the configuration is indicated at the beginning of the name; for example: O H Cl (R)-2-chloro-3-phenylpropanal A cyclic compound containing an aldehyde group immediately adjacent to the ring is named as a carbaldehyde: O H Cyclohexanecarbaldehyde klein_c20_001-056v1.4.indd 3 30/04/10 16.46 4 CHAPTER 20 Aldehydes and Ketones The International Union of Pure and Applied Chemistry (IUPAC) nomenclature also recognizes the common names of many simple aldehydes, including the three examples shown below: O O O HH H3C H H Formaldehyde Acetaldehyde Benzaldehyde Nomenclature of Ketones Ketones, like aldehydes, are named using the same four-step procedure. When naming the par- ent, the suffix “-one” indicates the presence of a ketone group: O Butane Butanone The position of the ketone group is indicated using a locant. The IUPAC rules published in 1979 dictate that this locant be placed immediately before the parent, while the IUPAC recom- mendations released in 1993 and 2004 allow for the locant to be placed immediately before the suffix “-one”: O 3-heptanone or 1357heptan-3-one 2 4 6 Both names above are acceptable IUPAC names. IUPAC nomenclature recognizes the common names of many simple ketones, including the three examples shown below: O O O CH3 H3CCH3 Acetone Acetophenone Benzophenone Although rarely used, IUPAC rules also allow simple ketones to be named as alkyl alkyl ketones. For example, 3-hexanone can also be called ethyl propyl ketone: O C Ethyl propyl ketone SKILLBUILDER 20.1 NAMING ALDEHYDES AND KETONES LEARN the skill *ÀÛ`iÊ>ÊÃÞÃÌi>ÌVÊ­1* ®Ê>iÊvÀÊÌ iÊvÜ}ÊV«Õ`\ O SOLUTION 8 79 STEP 1 / iÊwÀÃÌÊÃÌi«ÊÃÊÌÊ`iÌvÞÊ>`Ê>iÊÌ iÊ«>ÀiÌ°Ê ÃiÊÌ iÊ- 2 46 `iÌvÞÊ>`Ê>iÊÌ iÊ }iÃÌÊV >ÊÌ >ÌÊVÕ`iÃÊÌ iÊV>ÀLÞÊ}ÀÕ«]Ê>`ÊÌ iÊÕLiÀÊÌ iÊ 1 «>ÀiÌ° V >ÊÌÊ}ÛiÊÌ iÊV>ÀLÞÊ}ÀÕ«ÊÌ iÊÜiÃÌÊÕLiÀÊ«ÃÃLi\ 3 5 O 3-nonanone klein_c20_001-056v1.4.indd 4 30/04/10 16.46 20.2 Nomenclature 5 iÝÌ]Ê`iÌvÞÊÌ iÊÃÕLÃÌÌÕiÌÃÊ>`Ê>ÃÃ}ÊV>ÌÃ\ STEP 2 4,4-dimethyl 8 `iÌvÞÊ>`Ê>iÊÌ iÊ 79 ÃÕLÃÌÌÕiÌð STEP 3 2 46 1 ÃÃ}Ê>ÊV>ÌÊÌÊi>V Ê 3 5 ÃÕLÃÌÌÕiÌ° 6-ethyl O >Þ]Ê>ÃÃiLiÊÌ iÊÃÕLÃÌÌÕiÌÃÊ>« >LiÌV>Þ\ÊÈiÌ Þ{]{`iÌ ÞÎ>i°Ê ivÀiÊ VVÕ`}]ÊÜiÊÕÃÌÊ>Ü>ÞÃÊV iVÊÌÊÃiiÊvÊÌ iÀiÊ>ÀiÊ>ÞÊV À>ÌÞÊViÌiÀðÊ/ ÃÊV«Õ`Ê `iÃÊiÝ LÌÊiÊV À>ÌÞÊViÌiÀ°Ê1Ã}ÊÌ iÊÃÃÊvÀÊ-iVÌÊx°Î]ÊÌ iÊRÊVw}ÕÀ>ÌÊÃÊ STEP 4 ÃÃiLiÊÌ iÊ >ÃÃ}i`ÊÌÊÌ ÃÊV À>ÌÞÊViÌiÀ\ ÃÕLÃÌÌÕiÌÃÊ >« >LiÌV>Þ° STEP 5 ÃÃ}ÊÌ iÊVw}ÕÀ>ÌÊ R vÊ>ÞÊV À>ÌÞÊViÌiÀð O / iÀivÀi]ÊÌ iÊV«iÌiÊ>iÊÃÊ(R)-6-ethyl-4,4-dimethyl-3-nonanone. PRACTICE the skill 20.1 ÃÃ}Ê>ÊÃÞÃÌi>ÌVÊ­1* ®Ê>iÊÌÊi>V ÊvÊÌ iÊvÜ}ÊV«Õ`Ã\ O O H Br Br (a) O (b) (c) O OH H (d) (e) APPLY the skill 20.2 À>ÜÊÌ iÊÃÌÀÕVÌÕÀiÊvÊi>V ÊvÊÌ iÊvÜ}ÊV«Õ`Ã\ ­>® ­S®Î]Î`LÀ{iÌ ÞVÞV iÝ>iÊ Ê ­L®Ê Ó]{`iÌ ÞΫiÌ>i ­V® ­R®ÎLÀLÕÌ>> 20.3 *ÀÛ`iÊ>ÊÃÞÃÌi>ÌVÊ­1* ®Ê>iÊvÀÊÌ iÊV«Õ`ÊLiÜ°Ê iÊV>ÀivÕ\Ê/ ÃÊV- «Õ`Ê >ÃÊÌÜÊV À>ÌÞÊViÌiÀÃÊ­V>ÊÞÕÊw`ÊÌ i¶®° O 20.4 «Õ`ÃÊÜÌ ÊÌÜÊV>ÀLÞÊiÌiÃÊ>ÀiÊ>i`Ê>ÃÊ>>iÊ`iÃÆÊvÀÊiÝ>«i\ O O 2,3-butanedione / iÊV«Õ`Ê>LÛiÊÃÊ>Ê>ÀÌwV>Êy>ÛÀÊ>``i`ÊÌÊVÀÜ>ÛiÊ««VÀÊ>`ÊÛiÊ Ì i>ÌiÀÊ««VÀÊÌÊÃÕ>ÌiÊÌ iÊLÕÌÌiÀÊy>ÛÀ°ÊÌiÀiÃÌ}Þ]ÊÌ ÃÊÛiÀÞÊÃ>iÊV«Õ`ÊÃÊ >ÃÊÜÊÌÊVÌÀLÕÌiÊÌÊL`ÞÊ`À°Ê >iÊÌ iÊvÜ}ÊV«Õ`Ã\ O OO O (a)(b) (c) O OO need more PRACTICE? Try Problems 20.44–20.49 klein_c20_001-056v1.4.indd 5 30/04/10 16.46 6 CHAPTER 20 Aldehydes and Ketones 20.3 Preparing Aldehydes and Ketones: A Review In previous chapters, we have studied a variety of methods for preparing aldehydes and ketones, which are summarized in Tables 20.1 and 20.2, respectively. TABLE 20.1 A SUMMARY OF ALDEHYDE PREPARATION TABLE 20.2 A SUMMARY OF KETONE PREPARATION METHODS COVERED IN PREVIOUS CHAPTERS METHODS COVERED IN PREVIOUS CHAPTERS REACTION SECTION REACTION SECTION "Ý`>ÌÊvÊ*À>ÀÞÊV ÃÊ £Î°£äÊ "Ý`>ÌÊvÊ-iV`>ÀÞÊV ÃÊ £Î°£äÊ Ê OH O Ê OH O Ê Ê PCC Na2Cr2O7 Ê Ê CH Cl H SO ,HO ÊR 2 2 RH ÊRR 2 4 2 RR 7 iÊÌÀi>Ìi`ÊÜÌ Ê>ÊÃÌÀ}ÊÝ`â}Ê>}iÌ]Ê«À>ÀÞÊ>V ÃÊ ÊÊÛ>ÀiÌÞÊvÊÃÌÀ}ÊÀÊ`ÊÝ`â}Ê>}iÌÃÊV>ÊLiÊÕÃi`ÊÌÊ >ÀiÊÝ`âi`ÊÌÊV>ÀLÝÞVÊ>V`ðÊÀ>ÌÊvÊ>Ê>`i Þ`iÊ Ý`âiÊÃiV`>ÀÞÊ>V ðÊ/ iÊÀiÃÕÌ}ÊiÌiÊ`iÃÊÌÊ ÀiµÕÀiÃÊ>ÊÝ`â}Ê>}iÌ]ÊÃÕV Ê>ÃÊ* ]ÊÌ >ÌÊÜÊÌÊvÕÀÌ iÀÊ Õ`iÀ}ÊvÕÀÌ iÀÊÝ`>Ì° Ý`âiÊÌ iÊÀiÃÕÌ}Ê>`i Þ`i° "âÞÃÃÊvÊiiÃÊ °£Ê "âÞÃÃÊvÊiiÃÊ °£Ê RÊ R R R Ê Ê 1) O3 H H H H O O Ê 1) O Ê 2) DMS Ê 3 O O ÊR R R R 2) DMS ÊR R R R Ê/iÌÀ>ÃÕLÃÌÌÕÌi`Ê>iiÃÊ>ÀiÊVi>Ûi`ÊÌÊvÀÊiÌið Ê Ê"âÞÃÃÊÜÊVi>ÛiÊ>Ê 5 Ê`ÕLiÊL`°ÊvÊiÌ iÀÊV>ÀLÊ V` >Ì>Þâi`ÊÞ`À>ÌÊvÊ/iÀ>ÊÞiÃÊ £ä°nÊ >ÌÊLi>ÀÃÊ>Ê Þ`À}iÊ>Ì]Ê>Ê>`i Þ`iÊÜÊLiÊvÀi`° Ê O Ê H2SO4,H2O Þ`ÀLÀ>Ì"Ý`>ÌÊvÊ/iÀ>ÊÞiÃÊ £ä°nÊ Ê HgSO4 R CH Ê ÊR 3 1) R BH H Ê 2 R Ê/ ÃÊ«ÀVi`ÕÀiÊÀiÃÕÌÃÊÊ>Ê>ÀÛÛÊ>``ÌÊvÊÜ>ÌiÀÊ RÊ 2) H2O2, NaOH >VÀÃÃÊÌ iÊUÊL`]ÊvÜi`ÊLÞÊÌ>ÕÌiÀâ>ÌÊÌÊvÀÊ>Ê Ê O iÌ ÞÊiÌi° ÊÞ`ÀLÀ>ÌÝ`>ÌÊÀiÃÕÌÃÊÊ>Ê>Ì>ÀÛÛÊ>``- ÌÊvÊÜ>ÌiÀÊ>VÀÃÃÊ>ÊUÊL`]ÊvÜi`ÊLÞÊÌ>ÕÌiÀâ>ÌÊvÊ Ài`i À>vÌÃÊVÞ>ÌÊ £°ÈÊ Ì iÊÀiÃÕÌ}ÊiÊÌÊvÀÊ>Ê>`i Þ`i°Ê Ê O Ê O Ê R Ê Cl R Ê AlCl3 Ê À>ÌVÊÀ}ÃÊÌ >ÌÊ>ÀiÊÌÊÌÊÃÌÀ}ÞÊ`i>VÌÛ>Ìi`ÊÜÊÀi>VÌÊ ÜÌ Ê>Ê>V`Ê >`iÊÊÌ iÊ«ÀiÃiViÊvÊ>ÊiÜÃÊ>V`ÊÌÊ«À`ÕViÊ >Ê>ÀÞÊiÌi° CONCEPTUAL CHECKPOINT 20.5 `iÌvÞÊÌ iÊÀi>}iÌÃÊiViÃÃ>ÀÞÊÌÊ>V iÛiÊi>V ÊvÊÌ iÊvÜ}ÊÌÀ>ÃvÀ>ÌÃ\ OH O O OH O H (a) (b) (c) O H O O O H (d) (e) (f) klein_c20_001-056v1.4.indd 6 30/04/10 16.46 20.4 Introduction to Nucleophilic Addition Reactions 7 20.4 Introduction to Nucleophilic Addition Reactions The electrophilicity of a carbonyl group derives from resonance effects as well as inductive effects: Resonance Induction - d- O O O + d± One of the resonance structures exhibits a positive charge on the carbon atom, indicating that the carbon atom is deficient in electron density (I+).
Load more

Recommended publications
  • Brief Guide to the Nomenclature of Organic Chemistry
    1 Brief Guide to the Nomenclature of Table 1: Components of the substitutive name Organic Chemistry (4S,5E)-4,6-dichlorohept-5-en-2-one for K.-H. Hellwich (Germany), R. M. Hartshorn (New Zealand), CH3 Cl O A. Yerin (Russia), T. Damhus (Denmark), A. T. Hutton (South 4 2 Africa). E-mail: [email protected] Sponsoring body: Cl 6 CH 5 3 IUPAC Division of Chemical Nomenclature and Structure suffix for principal hept(a) parent (heptane) one Representation. characteristic group en(e) unsaturation ending chloro substituent prefix 1 INTRODUCTION di multiplicative prefix S E stereodescriptors CHEMISTRY The universal adoption of an agreed nomenclature is a key tool for 2 4 5 6 locants ( ) enclosing marks efficient communication in the chemical sciences, in industry and Multiplicative prefixes (Table 2) are used when more than one for regulations associated with import/export or health and safety. fragment of a particular kind is present in a structure. Which kind of REPRESENTATION The International Union of Pure and Applied Chemistry (IUPAC) multiplicative prefix is used depends on the complexity of the provides recommendations on many aspects of nomenclature.1 The APPLIED corresponding fragment – e.g. trichloro, but tris(chloromethyl). basics of organic nomenclature are summarized here, and there are companion documents on the nomenclature of inorganic2 and Table 2: Multiplicative prefixes for simple/complicated entities polymer3 chemistry, with hyperlinks to original documents. An No. Simple Complicated No. Simple Complicated AND overall
    [Show full text]
  • Aldehydes and Ketones (Pp. 916-920)
    Aldehydes and Ketones Klein, D. (2012). Aldehydes and Ketones. En Organic Chemistry (pp. 916-920). USA: Wiley. Espacio de Formación Multimodal 20.2 Nomenclature 917 916 CHAPTER 20 Aldehydes and Ketones 20.2 Nomenclature DO YOU REMEMBER? Before you go on, be sure you understand the following topics. If necessary, review the suggested sections Nomenclature of Aldehydes to prepare for this chapter: Recall that four discrete steps are required to name most classes of organic compounds (as we UÊ À}>À`ÊÀi>}iÌÃÊ­-iVÌʣΰȮÊÊ UÊ ,iÌÀÃÞÌ iÌVÊ>>ÞÃÃÊ­-iVÌÊ£Ó°x® saw with alkanes, alkenes, alkynes, and alcohols): UÊ "Ý`>ÌÊvÊ>V ÃÊ­-iVÌʣΰ£ä® 1. Identify and name the parent. 6ÃÌÊÜÜÜ°ÜiÞ«ÕðVÊÌÊV iVÊÞÕÀÊÕ`iÀÃÌ>`}Ê>`ÊvÀÊÛ>Õ>LiÊ«À>VÌVi° Ê 2. Identify and name the substituents. 3. Assign a locant to each substituent. 4. Assemble the substituents alphabetically. Aldehydes are also named using the same four-step procedure. When applying this procedure 20.1 Introduction to Aldehydes and Ketones for naming aldehydes, the following guidelines should be followed: When naming the parent, the suffix “-al” indicates the presence of an aldehyde group: Aldehydes (RCHO) and ketones (R2CO) are similar in structure in that both classes of com- pounds possess a CO bond, called a carbonyl group: O Carbonyl Group H Butane Butanal O O When choosing the parent of an aldehyde, identify the longest chain that includes the carbon RH RR atom of the aldehydic group: An aldehyde A ketone The parent The carbonyl group of an aldehyde is flanked by a hydrogen atom, while the carbonyl group of must include HO a ketone is flanked by two carbon atoms.
    [Show full text]
  • Soln-2212-PT3-S20-Ch-16-18.Pdf
    1. 2. H2SO4 H2SO4 H2SO41) BH3, THF 1) BH3, THF 1) BH3, THF - - - 2) OH , H2O2, H2O2) OH , H2O2, H2O 2) OH , H2O2, H2O OH OH OH 3. OH OH OH H2SO4 1) BH3, THF - 2) OH , H2O2, H2O OH PBr3 PBr3 PBr3 Pyridine Pyridine Pyridine OH PBr3 Pyridine O O O Mg Mg Mg HO HO HO1) 1) 1) Ether Ether Ether 2) HCl 2) HCl 2) HCl Br Br Br MgBr MgBr MgBr O Mg HO 1) Ether 2) HCl Br 4. MgBr **This reaction reduces an aldehyde to a primary alcohol and a ketone to a secondary alcohol. Since only one EQ of reagent is given the most reactive functional group will be reduced (in this case the aldehyde) **ketones are less reactive than aldehydes and the more steric hindrance surrounding the ketone the less reactive it is. Note: NaBH4 reduces ketones but is too weak to reduce an ester/double/triple bonds 5. ** With these reagents a tertiary amide will be reduced to a tertiary amine, a secondary amide will be reduced to a secondary amine, and a primary amide will be reduced to a primary amine 6. ** Recall from chapter 7, OChem 1 H2 and Lindlars catalyst always reduces an alkyne to a CIS ALKENE ** Li/Na and liquid NH3 always reduces an alkyne to a TRANS ALKENE 7. **A ketone/aldehyde reacts with primary amines in trace acid to produce an imine, and reacts with a secondary amine in trace acid to produce an enamine (double bond forms between the alpha and beta carbons) **Sodium cyanoborohydride (NaBH3CN) is used to reduce imines/enamines back to their respective secondary/tertiary amines 8.
    [Show full text]
  • Nomenclature of Steroids
    Pure&App/. Chern.,Vol. 61, No. 10, pp. 1783-1822,1989. Printed in Great Britain. @ 1989 IUPAC INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY and INTERNATIONAL UNION OF BIOCHEMISTRY JOINT COMMISSION ON BIOCHEMICAL NOMENCLATURE* NOMENCLATURE OF STEROIDS (Recommendations 1989) Prepared for publication by G. P. MOSS Queen Mary College, Mile End Road, London El 4NS, UK *Membership of the Commission (JCBN) during 1987-89 is as follows: Chairman: J. F. G. Vliegenthart (Netherlands); Secretary: A. Cornish-Bowden (UK); Members: J. R. Bull (RSA); M. A. Chester (Sweden); C. LiCbecq (Belgium, representing the IUB Committee of Editors of Biochemical Journals); J. Reedijk (Netherlands); P. Venetianer (Hungary); Associate Members: G. P. Moss (UK); J. C. Rigg (Netherlands). Additional contributors to the formulation of these recommendations: Nomenclature Committee of ZUB(NC-ZUB) (those additional to JCBN): H. Bielka (GDR); C. R. Cantor (USA); H. B. F. Dixon (UK); P. Karlson (FRG); K. L. Loening (USA); W. Saenger (FRG); N. Sharon (Israel); E. J. van Lenten (USA); S. F. Velick (USA); E. C. Webb (Australia). Membership of Expert Panel: P. Karlson (FRG, Convener); J. R. Bull (RSA); K. Engel (FRG); J. Fried (USA); H. W. Kircher (USA); K. L. Loening (USA); G. P. Moss (UK); G. Popjiik (USA); M. R. Uskokovic (USA). Correspondence on these recommendations should be addressed to Dr. G. P. Moss at the above address or to any member of the Commission. Republication of this report is permitted without the need for formal IUPAC permission on condition that an acknowledgement, with full reference together with IUPAC copyright symbol (01989 IUPAC), is printed.
    [Show full text]
  • Naming Organic Chemicals Naming Organic Chemicals
    B11CC3B17CA Naming Organic Chemicals B17CA Naming Organic Chemicals Naming Alkenes Alkenes are named in the same way that alkanes are named except that you use -ene as the stem ending. A comprehensive set of nomenclature rules has been devised by the International Union of Pure and The parent chain for the name is the longest chain containing the alkene group. Applied Chemistry (IUPAC). This sheet explains basic chemical nomenclature. Use a locant to indicate the position of the alkene and number from the end of the chain that gives the lowest value to this locant. Naming Alkanes 5 8 Straight chain alkanes are named with a stem to indicate the number of carbons in the chain followed CH2CH2CH2CH3 by the ending -ane. 1 ALKANE CH3CH2CH2CHCH3 4-methyloctane 4 methane CH4 hexane CH3CH2CH2CH2CH2CH3 ethane CH3CH3 heptane CH3CH2CH2CH2CH2CH2CH3 5 3 2 8 propane CH CH CH octane CH CH CH CH CH CH CH CH 3 2 3 3 2 2 2 2 2 2 3 CH2CH CHCH3 butane CH3CH2CH2CH3 nonane CH3CH2CH2CH2CH2CH2CH2CH2CH3 8 pentane CH CH CH CH CH decane CH CH CH CH CH CH CH CH CH CH ALKENE CH3CH2CH2CHCH3 5-methyloct-2-ene 3 2 2 2 3 3 2 2 2 2 2 2 2 2 3 5 For branched alkanes choose the longest chain as the parent chain for the name and include the side locant indicates position of double bond chains as substituent prefixes: methyl-, ethyl-, propyl-, butyl- etc. stem ending -ene 5 8 Notice that the locant indicating the position of the double bond is located BEFORE the ending 1 CH2CH2CH2CH3 4-methyloctane ‘-ene’.
    [Show full text]
  • Advantages of Nodal Numbering for Uniquely Identifying Atoms in Chemical Nomenclature Alan L
    CROATICA CHEMICA ACTA CCACAA 59 (3) 547-563 (198G)1 YU ISSN 0011-1643 CCA-1668 UDC 541 Original Scientific Paper Advantages of Nodal Numbering for Uniquely Identifying Atoms in Chemical Nomenclature Alan L. Goodson 1060 Woodmere Road, CoLumbus, Ohio 43220, U.S.A. and Noel Lozac'h Institut des Sciences de la Matiere et du Rayonnement, Universite de Caen, 14032 Caen Cedex, France Received September 2, 1985 There are situations in chemical nomenclature where duplica- tion of locants creates difficulties (a) in describing modifications to chemical structures, (b) in describing stereochemistry, (c) in identifying isotopically-labeled atoms, and (d) in uniquely iden- tifying atoms for crystallography, Nodal nomenclature is shown to avoid these problems and to simplify such descriptions. INTRODUCTION The first concerted international agreements on chemical nornenclature- were made in Geneva in 18921. From these agreements has aris en the Inter- national Union of Pure and Applied Chemistry (IUPAC), as we know it today. IUPAC has, in general, »confined its efforts to codifying sound practices. which already existed-". IUPAC has published a set of internationally-agreed rules of organic chemistry", However, more than one sound practice is some- times described (e. g., for naming organic compounds containing phosphorus,. arsenic, antimony or bismuth) without any indication of which practice is preferred. For practical reasons, indexers of chemical literature, such as Chemical Abstracts Service and Beilstein, must be more selective, i. e. more systematic, than IUP AC and must even develop their own rules when IUP AC rules are vague or non-existent. The rules published by IUP AC include the powerful and commonly-used technique of substitutive nomenclature.
    [Show full text]
  • Organic Chemistry Third Edition
    Organic Chemistry Third Edition David Klein Chapter 19 Aldehydes and Ketones Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. Klein, Organic Chemistry 3e 19.1 Ketones And Aldehydes • Both functionAl groups possess the cArbonyl group • ImportAnt in both biology And industry Simplest aldehyde Simplest ketone used as a used mainly as preservative a solvent Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. 19-2 Klein, Organic Chemistry 3e 19.1 Ketones And Aldehydes Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. 19-3 Klein, Organic Chemistry 3e 19.2 NomenclAture • Four discrete steps to nAming An Aldehyde or ketone • SAme procedure As with AlkAnes, Alcohols, etc… 1. Identify and name the parent chain 2. Identify the nAme of the substituents (side groups) 3. Assign A locant (number) to eAch substituents 4. Assemble the nAme AlphAbeticAlly Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. 19-4 Klein, Organic Chemistry 3e 19.2 NomenclAture 1. Identify and name the parent chain – For Aldehydes, replAce the “-e” ending with An “-al” – the parent chain must include the cArbonyl cArbon Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. 19-5 Klein, Organic Chemistry 3e 19.2 NomenclAture 1. Identify and name the parent chain – The Aldehydic cArbon is Assigned number 1: Copyright © 2017 John Wiley & Sons, Inc. All rights reserved. 19-6 Klein, Organic Chemistry 3e 19.2 NomenclAture 1. Identify and name the parent chain – For ketones, replAce the “-e” ending with an “-one” – The pArent chAin must include the C=O group – the C=O cArbon is given the lowest #, And can be expressed before the pArent nAme or before the suffix Copyright © 2017 John Wiley & Sons, Inc.
    [Show full text]
  • Organic Chemistry 1 Lecture 3
    CHEM 232 University of Illinois Organic Chemistry I at Chicago UIC Organic Chemistry 1 Lecture 3 Instructor: Prof. Duncan Wardrop Time/Day: T & R, 12:30-1:45 p.m. January 19, 2010 1 Lecture Summary Revision & Proof of Resonance Introduction to Hydrocarbons Classi!cation Structure & Bonding Nomenclature University of Slide 2 CHEM 232, Spring 2010 Illinois at Chicago UIC Lecture 3: January 19 2 Revision of Resonance Do not confuse equilibrium with resonance: double-headed arrows represent resonance contributors; two separate arrows represent the equilibrium of distinct chemical species.... O O Resonance (electrons move) MeO MeO H O O H H H Equilibrium (atoms move) University of Slide 3 CHEM 232, Spring 2010 Illinois at Chicago UIC Lecture 3: January 19 3 The first pair of structures are descriptions of the same molecule - the overall description is based on a weighted combination of the two extremes. The second pair of structures are distinct molecules: one is a ketone and the other an enol. For more details about this chemical transformation, see Chapter 18. Prioritizing Resonance Contributors (How much Unicorn?!) Priority 1 No !rst-row elements (B, C, N, O) can have more than eight electrons in its valence shell..... O O O N N N O O O Equal Equal Non-Permissable Contributor Contributor Contributor (N has 10 elect.) University of Slide 4 CHEM 232, Spring 2010 Illinois at Chicago UIC Lecture 3: January 19 4 Prioritizing Resonance Contributors Priority 2 Resonance structures in which all atoms are surrounded by an octet of electrons are almost always lower in energy than those resonance structures in which one or more atoms are electron de!cient.
    [Show full text]
  • ACS Style Guide
    ➤ ➤ ➤ ➤ ➤ The ACS Style Guide ➤ ➤ ➤ ➤ ➤ THIRD EDITION The ACS Style Guide Effective Communication of Scientific Information Anne M. Coghill Lorrin R. Garson Editors AMERICAN CHEMICAL SOCIETY Washington, DC OXFORD UNIVERSITY PRESS New York Oxford 2006 Oxford University Press Oxford New York Athens Auckland Bangkok Bogotá Buenos Aires Calcutta Cape Town Chennai Dar es Salaam Delhi Florence Hong Kong Istanbul Karachi Kuala Lumpur Madrid Melbourne Mexico City Mumbai Nairobi Paris São Paulo Singapore Taipei Tokyo Toronto Warsaw and associated companies in Berlin Idaban Copyright © 2006 by the American Chemical Society, Washington, DC Developed and distributed in partnership by the American Chemical Society and Oxford University Press Published by Oxford University Press, Inc. 198 Madison Avenue, New York, NY 10016 Oxford is a registered trademark of Oxford University Press All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the American Chemical Society. Library of Congress Cataloging-in-Publication Data The ACS style guide : effective communication of scientific information.—3rd ed. / Anne M. Coghill [and] Lorrin R. Garson, editors. p. cm. Includes bibliographical references and index. ISBN-13: 978-0-8412-3999-9 (cloth : alk. paper) 1. Chemical literature—Authorship—Handbooks, manuals, etc. 2. Scientific literature— Authorship—Handbooks, manuals, etc. 3. English language—Style—Handbooks, manuals, etc. 4. Authorship—Style manuals. I. Coghill, Anne M. II. Garson, Lorrin R. III. American Chemical Society QD8.5.A25 2006 808'.06654—dc22 2006040668 1 3 5 7 9 8 6 4 2 Printed in the United States of America on acid-free paper ➤ ➤ ➤ ➤ ➤ Contents Foreword.
    [Show full text]
  • Introduction (Pdf)
    Dictionary of Natural Products on CD-ROM This introduction screen gives access to (a) a general introduction to the scope and content of DNP on CD-ROM, followed by (b) an extensive review of the different types of natural product and the way in which they are organised and categorised in DNP. You may access the section of your choice by clicking on the appropriate line below, or you may scroll through the text forwards or backwards from any point. Introduction to the DNP database page 3 Data presentation and organisation 3 Derivatives and variants 3 Chemical names and synonyms 4 CAS Registry Numbers 6 Diagrams 7 Stereochemical conventions 7 Molecular formula and molecular weight 8 Source 9 Importance/use 9 Type of Compound 9 Physical Data 9 Hazard and toxicity information 10 Bibliographic References 11 Journal abbreviations 12 Entry under review 12 Description of Natural Product Structures 13 Aliphatic natural products 15 Semiochemicals 15 Lipids 22 Polyketides 29 Carbohydrates 35 Oxygen heterocycles 44 Simple aromatic natural products 45 Benzofuranoids 48 Benzopyranoids 49 1 Flavonoids page 51 Tannins 60 Lignans 64 Polycyclic aromatic natural products 68 Terpenoids 72 Monoterpenoids 73 Sesquiterpenoids 77 Diterpenoids 101 Sesterterpenoids 118 Triterpenoids 121 Tetraterpenoids 131 Miscellaneous terpenoids 133 Meroterpenoids 133 Steroids 135 The sterols 140 Aminoacids and peptides 148 Aminoacids 148 Peptides 150 β-Lactams 151 Glycopeptides 153 Alkaloids 154 Alkaloids derived from ornithine 154 Alkaloids derived from lysine 156 Alkaloids
    [Show full text]
  • Principles of Chemical Nomenclature a GUIDE to IUPAC RECOMMENDATIONS Principles of Chemical Nomenclature a GUIDE to IUPAC RECOMMENDATIONS
    Principles of Chemical Nomenclature A GUIDE TO IUPAC RECOMMENDATIONS Principles of Chemical Nomenclature A GUIDE TO IUPAC RECOMMENDATIONS G.J. LEIGH OBE TheSchool of Chemistry, Physics and Environmental Science, University of Sussex, Brighton, UK H.A. FAVRE Université de Montréal Montréal, Canada W.V. METANOMSKI Chemical Abstracts Service Columbus, Ohio, USA Edited by G.J. Leigh b Blackwell Science © 1998 by DISTRIBUTORS BlackweilScience Ltd Marston Book Services Ltd Editorial Offices: P0 Box 269 Osney Mead, Oxford 0X2 0EL Abingdon 25 John Street, London WC1N 2BL Oxon 0X14 4YN 23 Ainslie Place, Edinburgh EH3 6AJ (Orders:Tel:01235 465500 350 Main Street, Maiden Fax: MA 02 148-5018, USA 01235 465555) 54 University Street, Carlton USA Victoria 3053, Australia BlackwellScience, Inc. 10, Rue Casmir Delavigne Commerce Place 75006 Paris, France 350 Main Street Malden, MA 02 148-5018 Other Editorial Offices: (Orders:Tel:800 759 6102 Blackwell Wissenschafts-Verlag GmbH 781 388 8250 KurfUrstendamm 57 Fax:781 388 8255) 10707 Berlin, Germany Canada Blackwell Science KK Copp Clark Professional MG Kodenmacho Building 200Adelaide St West, 3rd Floor 7—10 Kodenmacho Nihombashi Toronto, Ontario M5H 1W7 Chuo-ku, Tokyo 104, Japan (Orders:Tel:416 597-1616 800 815-9417 All rights reserved. No part of Fax:416 597-1617) this publication may be reproduced, stored in a retrieval system, or Australia BlackwellScience Pty Ltd transmitted, in any form or by any 54 University Street means, electronic, mechanical, Carlton, Victoria 3053 photocopying, recording or otherwise, (Orders:Tel:39347 0300 except as permitted by the UK Fax:3 9347 5001) Copyright, Designs and Patents Act 1988, without the prior permission of the copyright owner.
    [Show full text]
  • Alkynes • Alkynes Are Molecules That Incorporate a C≡C Triple Bond
    10.1 Alkynes • Alkynes are molecules that incorporate a C≡C triple bond. Copyright 2012 John Wiley & Sons, Inc. 10 -1 Klein, Organic Chemistry 1e 10.1 Alkynes • Given the presence of two pi bonds and their associated electron density, alkynes are similar to alkenes in their ability to act as a nucleophile. • Converting pi bonds to sigma bonds generally makes a molecule more stable. WHY? Copyright 2012 John Wiley & Sons, Inc. 10 -2 Klein, Organic Chemistry 1e 10.1 Alkyne Uses • Acetylene is the simplest alkyne. – It is used in blow torches and as a precursor for the synthesis of more complex alkynes. • More than 1000 different alkyne natural products have been isolated. – One example is histrionicotoxin, which can be isolated from South American frogs, and is used on poison-tipped arrows by South American tribes. Copyright 2012 John Wiley & Sons, Inc. 10 -3 Klein, Organic Chemistry 1e 10.1 Alkyne Uses • An example of a synthetic alkyne is ethynylestradiol. • Ethynylestradiol is the active ingredient in many birth control pills. • The presence of the triple bond increases the potency of the drug compared to the natural analog. • How do you think a C≡C triple bond affects the molecule’s geometry? Its rigidity? Its intermolecular attractions? Copyright 2012 John Wiley & Sons, Inc. 10 -4 Klein, Organic Chemistry 1e 10.2 Alkyne Nomenclature • Alkynes are named using the same procedure we used in Chapter 4 to name alkanes with minor modifications: 1. Identify the parent chain, which should include the C≡C triple bond. 2. Identify and name the substituents.
    [Show full text]