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The Carbonyl

Carbonyl carbons readily undergo nucleophilic attack. [Pg.55]


They are stable compounds and are not decomposed by dilute acids or alkalis. They are frequently employed in synthetic organic chemistry for protecting the carbonyl group. [Pg.254]

The effects of TIP also appear in figure B 1,11.3 and figure B 1.11.4. In the NMR spectrum, all the resonances of the sp carbons lie above 100 ppm (a usefiil general rule of thumb) because A is smaller for multiple bonds. The highest shifts are for the carbonyl C at 169 ppm and the ring C attached to oxygen at 155... [Pg.1447]

Figure C2.3.9. Product distribution of dissymmetrical ketone photolysis as influenced by cefyltrimethylammonium chloride (CTAC) micelles. The initial ketone, A(CO)B is photolysed to lose the carbonyl group and to produce tliree products, AA, AB and BB. These data are for benzyl (A) 4-methylbenzyl (B) ketone. Product AA is 1,2-diphenylethane, product BB is 1,2-ditolylethane and product AB is l-phenyl-2-tolyl-ethane. At low CTAC concentration, in the absence of micelles, a random distribution of products is obtained. In the presence of micelles, however, the AB product is heavily favoured. Adapted with pennission from 1571. Figure C2.3.9. Product distribution of dissymmetrical ketone photolysis as influenced by cefyltrimethylammonium chloride (CTAC) micelles. The initial ketone, A(CO)B is photolysed to lose the carbonyl group and to produce tliree products, AA, AB and BB. These data are for benzyl (A) 4-methylbenzyl (B) ketone. Product AA is 1,2-diphenylethane, product BB is 1,2-ditolylethane and product AB is l-phenyl-2-tolyl-ethane. At low CTAC concentration, in the absence of micelles, a random distribution of products is obtained. In the presence of micelles, however, the AB product is heavily favoured. Adapted with pennission from 1571.
Hydroxylamine condenses with the carbonyl group of an aldehyde or ketone to form an oxime ... [Pg.223]

Hydrazine and its alkylated derivatives are used as rocket fuels in organic chemistry, substituted phenylhydrazines are important in the characterisation of sugars and other compounds, for example aldehydes and ketones containing the carbonyl group C=0. [Pg.224]

Iron forms the carbonyls FelCO),. Fe2(CO)g and FcjlCOlij- In iron pentacarbonyl. the iron(O) is 5-coordinated. as shown in Figure 13.5 to give a trigonal bipyramid the substance is volatile... [Pg.398]

Fig. 1. The rate-determining step in the neutral hydrolysis of paramethoxy-phenyl dichloroacetate. In the reactant state (a) a water molecule is in proximity of the carbonyl carbon after concerted proton transfer to a second water molecule and electron redistribution, a tetrahedral intermediate (b) is formed. Fig. 1. The rate-determining step in the neutral hydrolysis of paramethoxy-phenyl dichloroacetate. In the reactant state (a) a water molecule is in proximity of the carbonyl carbon after concerted proton transfer to a second water molecule and electron redistribution, a tetrahedral intermediate (b) is formed.
Figure 2-51. a) The rotational barrier in amides can only be explained by VB representation using two resonance structures, b) RAMSES accounts for the (albeit partial) conjugation between the carbonyl double bond and the lone pair on the nitrogen atom. [Pg.66]

Fig. 12.20 4-Acetamido benzoic acid. Triangle smoothing predicts that the lower bound distance between the amide nitrogen and the carbonyl oxygen is equal to the sum of the van der Waals radii. The actual distance is about 6.4A. Fig. 12.20 4-Acetamido benzoic acid. Triangle smoothing predicts that the lower bound distance between the amide nitrogen and the carbonyl oxygen is equal to the sum of the van der Waals radii. The actual distance is about 6.4A.
When camphor (I) is heated with selenium dioxide in acetic acid, the methylene group next to the carbonyl group is oxidised also to a carbonyl group, to form camphorquinone (II). Note that the compound (II) is not a true quinone but a 1,2-diketone ... [Pg.147]

The mechanism of the reduction remains uncertain. The work of E. D. Williams, K. A. Krieger and A. R. Day (1953) using deuterium-labelled aluminium isopropoxide, shows that hydrogen atoms are transferred predominantly from the central carbon atom of an isopropoxide group to the carbon atom of the carbonyl group undergoing reduction, the process probably involving a cyclic complex ... [Pg.153]

Aldehydes and ketones may be converted into the corresponding primary amines by reduction of their oximes or hydrazones (p. 93). A method of more limited application, known as the Leuckart Reaction, consists of heating the carbonyl compound with ammonium formate, whereby the formyLamino derivative is formed, and can be readily hydrolysed by acids to the amine. Thus acetophenone gives the i-phenylethylformamide, which without isolation can be hydrolysed to i-phenylethylamine. [Pg.223]

The term Knoevenagel Condensation was originally applied to the base-catalysed condensation of the carbonyl ( CO) group of aldehydes and ketones with the reactive methylene group of malonic acid, with loss of w ater ... [Pg.279]

The role of the base is apparently primarily that of a proton remover from the reactive methylene group thus if B represents the base, reaction (i) gives the carbanion, which then combines with the positive carbon of the carbonyl group (reaction ii) the product regains a proton from the piperidinium ion, and then by loss of water followed by mono-decarboxylation of the malonic acid residue gives the final acid. [Pg.279]

Aldehydes form addition products at the double bond of the carbonyl (>C 0) group, and hydrolysis gives secondary alcohols. Thus acetaldehyde gives isopropyl alcohol ... [Pg.282]

The following reactions are characteristic of aliphatic aldehydes those which are shared by ketones, due to the presence of the carbonyl group, are given under Aliphatic Ketones (Section 111,74). [Pg.330]

The carbonyl compound may be mixed with an aqueous solution of sodium or potassium cyanide and mineral acid is added, or the bisulphite compound may be treated with an equivalent quantity of sodium cyanide, for example ... [Pg.341]

Most of the characteristic reactions of ketones (RR CO) depend upon condensation with substituted amines. The reactions occur between the carbonyl group and the —NHj group of the substituted amine, and hence are also shared by aldehydes RHCO ... [Pg.341]

Suspend 0 25 g. of 2 4-dinitrophenylhydrazine in 5 ml. of methanol and add 0-4 0-5 ml. of concentrated sulphuric acid cautiously. FUter the warm solution and add a solution of 0 1-0-2 g. of the carbonyl compound in a small volume of methanol or of ether. If no sohd separate within 10 minutes, dUute the solution carefuUy with 2N sulphuric acid. CoUect the solid by suction filtration and wash it with a little methanol. RecrystaUise the derivative from alcohol, dUute alcohol, alcohol with ethyl acetate or chloroform or acetone, acetic acid, dioxan, nitromethane, nitrobenzene or xylene. [Pg.344]

For the preparation of 2 4-dinitrophenylhydrazones, dissolve the carbonyl compound (say, 0-5 g.) in 5 ml. of ethanol and add the cal culated volume of the reagent. If a precipitate does not form immediately, dilute with a little water. Collect the derivative and recrystalhse it as above. [Pg.344]

By treatment of an amide with sodium hypobromite or sodium hypochlorite solution (or with the halogen and alkali), the amine of one less carbon atom is produced, the net result being the elimination of the carbonyl group. An example is ... [Pg.413]

With concentrated alkali, fission occurs at the position adjacent to the carbonyl group to give acetic acid and a mono-substituted acetic acid the process is termed acid hydrolysis. [Pg.475]

The first step is the interaction of the basic catalyst with the ester to produce the carbanion (I) the carbanion so formed then attacks the carbonyl carbon of a second molecule of ester to produce the anion (II), which is converted to ethyl acetoacetate (II) by the ejection of an ethoxide ion. Finally (III) reacts with ethoxide ion to produce acetoacetic ester anion (IV). This and other anions are mesomeric thus (IV) may be written ... [Pg.476]

Phthalic anhydride may be used as the carbonyl compound in the Perkin reaction see the preparation of phthalylacetic acid under Ninhytlrin (Section VIII,14),... [Pg.708]

It should be noted that the Friedel-Crafts acylation differs from the Friedel-Crafts alkylation (compare Sections IV,3-4 and discussion preceding Section IV,1) in one important respect. The alkylation requires catal3d.ic quantities of aluminium chloride, but for acylation a molecular equivalent of aluminium chloride is necessary for each carbonyl group present in the acylating agent. This is because aluminium chloride is capable of forming rather stable complexes with the carbonyl group these complexes probably possess an oxonium... [Pg.725]

Reaction of the cnrbaiilon (acetone anion) with the carbonyl carbon of ethyl acetate, accompanied by the release of an ethoxide ion, to form acetyl-acetone ... [Pg.862]

Lithium aluminium hydride LiAlH is a useful and conveuient reagent for the selective reduction of the carbonyl group and of various other polar functional groups. It is obtained by treatment of finely powdered lithium hydride with an ethereal solution of anhydrous aluminium chloride ... [Pg.877]


See other pages where The Carbonyl is mentioned: [Pg.50]    [Pg.13]    [Pg.36]    [Pg.82]    [Pg.231]    [Pg.232]    [Pg.256]    [Pg.56]    [Pg.1443]    [Pg.398]    [Pg.65]    [Pg.183]    [Pg.265]    [Pg.267]    [Pg.198]    [Pg.594]    [Pg.676]    [Pg.707]    [Pg.95]    [Pg.153]    [Pg.341]    [Pg.510]    [Pg.722]    [Pg.748]   


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ALDEHYDES AND KETONES NUCLEOPHILIC ADDITION TO THE CARBONYL GROUP

Acid catalysts increase the reactivity of a carbonyl group

Activating the carbonyl derivative

Activation of the carbonyl

Activation of the carbonyl group

Activation of the carbonyl substrate

Addition to the Carbonyl Bond

Addition to the Carbonyl Group

Affecting the Carbonyl Group

Aldehyde An organic compound containing the carbonyl group bonded to at least one

Aldehydes and Ketones The Carbonyl Group

Alkane picosecond carbon-hydrogen bond cleavage at the iridium carbonyl center

Alkylating the a-Carbon of Carbonyl Compounds

Alkylation with Carbonyl Compounds The Prins Reaction

Attack by Enolates on the Carbonyl Function Aldol Condensation

Between the Same Metals in Carbonyls and Their Derivatives

By Alan Cox 2 Reduction of the Carbonyl Group

CAS REGISTRY NUMBERS AND SYNONYMS FOR THE CARBONYL HALIDES

Calculation of the Conjugated Carbonyl Contents

Carbonyl Chemistry 2 Reactions at the a Position

Carbonyl Condensation Reactions in Synthesis The Robinson Annulation Reaction

Carbonyl Condensations The Aldol Reaction

Carbonyl Condensations with Enamines The Stork Reaction

Carbonyl Groups Located on the Same Ring

Carbonyl reduction by the Cannizzaro reaction

Carboxylic Acids with a Carbonyl Group at the 3-Position Can Be Decarboxylated

Characteristics of the Carbonyls

Chemistry of the Metal Carbonyls

Compounds containing the carbonyl group

Conjugate Carbonyl Additions The Michael Reaction

Deoxygenation of the Carbonyl Group

Dihydro Derivatives Containing a Carbonyl Group in the Ring

Dihydro Derivatives without a Carbonyl Group in the Ring

ELECTRONIC STRUCTURE OF THE CARBONYL HALIDES

Electron Affinities of Organic Carbonyl Compounds by the ECD

Electronic effect on the destabilization of carbonyl and

Electrophilicity of the carbonyl carbon atom

Elongation through the Aldonolactone Carbonyl Group

Enolisation, the first stage of carbonyl reactions

Enolizable Carbonyl Compounds the Haloform Reaction

Free Radical Methods for the Synthesis of Carbonyl Compounds

From the reactions of carbonyl difluoride or formyl fluoride

General Remarks on the Electronic Structure of Nickel Carbonyl

Hydrogen Abstraction by Groups Other Than the Carbonyl

Hydrogenation of the Carbonyl Group

In the synthesis of, carbonyl difluoride

Iridium Reactivity in the Methanol Carbonylation Reaction

Isolated Double Bonds in the Presence of a Carbonyl Group

Key Steps in the Mechanism of Carbonylation Processes

LUMO of the carbonyl group

Mechanistic Pathways in the Catalytic Carbonylation of Methanol by Rhodium and

Mechanistic Pathways in the Catalytic Carbonylation of Methanol by Rhodium and Iridium

Mechanistic Pathways in the Catalytic Carbonylation of Methanol by Rhodium and Iridium Complexes

Methylation of carbonyl compounds by the Wittig

Microwave-Promoted Carbonylations Using the Solvent as a Source of Carbon Monoxide

Nature of the Ylide and Carbonyl Compound

Nature of the carbonyl groups

Nucleophilic addition to the carbonyl group

Nucleophilic attack at the carbonyl group

Nucleophilic substitution at the carbonyl group

Other Developments Originating from the Study of Metal Carbonyls

Other Reactions at the Carbonyl Carbon Atom

Oxidation of Alcohols to Carbonyl Compounds with Activated Dimethyl Sulfoxide via Alkoxysulfonium Ylides. The Swern, Moffatt, and Related Oxidations

Oxidation of the Carbonyl Functionality

Photochemical reactions of the carbonyl group

Photocycloadditions of the Carbonyl Group

Polarization of the carbonyl double

Poly in the synthesis of, carbonyl difluoride

Preparation of the Metal Carbonyls

Protection for the Carbonyl Group

Reaction at the Carbonyl Group

Reactions at the Carbonyl Carbon of Acid Derivatives

Reactions at the Carbonyl Group—Adding or Removing One Carbon Atom

Reactions at the Carbonyl Group—Oxidation and Reduction

Reactions at the Metal Carbonyl Group

Reactions at the a Carbon of Carbonyl Compounds Enols and Enolates

Reactions of the Carbonyl Group

Reactivity of the Carbonyl Group

Reduction of the carbonyl group

Reversal of the Carbonyl Group Polarity (Umpolung)

Selectivity in the Reduction of Carbonyl Derivatives Containing a Chiral Carbon

Some Acid-Base-catalyzed Reactions of the Carbonyl Group

Structure and Bonding The Carbonyl Group

Structure of the Carbonyl Group

Substitution Products of the Group VIB Metal Carbonyls

Substitution Reactions of Carbonyl Compounds at the a Carbon

Substitution at the carbonyl group

Substitutions at the Carbonyl Group Reactions of Carboxylic Acids and Derivatives

Survey of the Cationic Metal Carbonyls and Their Properties by Groups

THE PREPARATION OF CARBONYL DIBROMIDE

The Alkyne Cobalt Carbonyl Complexes

The Carbonyl Bond

The Carbonyl Group

The Carbonyl Ligand

The Carbonyl ene Reaction

The Carbonylation of Methanol Catalyzed by Rhodium Complexes in Solution

The Carbonylative Heck Reaction

The Exchange of Carbonyl Compounds with Water

The Formation of Oxetanes from Carbonyls and Olefins

The Intensities of Carbonyl Absorptions

The Metal Carbonyls

The Photochemistry of Carbonyl Compounds

The Physical Properties of Carbonyl Compounds

The Reactions of Carbonyl Compounds with Hydride Ion

The Relative Reactivities of Carbonyl Compounds

The Role of Proximal, Lewis Basic Functional Groups in Carbonyl Reduction

The Stereochemistry of Carbonyl Reduction

The Wittig and Related Carbonyl Olefination Reactions

The carbonyl analogy

The interaction of carbonyl-containing compounds with organometallic reagents

The structures of carbonyls and related compounds

Thermo- and Photochemical Reactions of Carbonyl Compounds in the Solid State

Transformations of the Carbonyl Functions

Transposition of the Carbonyl Group

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