Organic Chemistry: Carbonyls, Carboxylic Acids and Chirality

Chirality and Optical IsomerismSign up

know that optical isomerism is a result of chirality in molecules with a single chiral centre · understand that optical isomerism results from chiral centre(s) in a molecule with asymmetric carbon atom(s) and that optical isomers (enantiomers) are object and non-superimposable mirror images and be able to draw 3D diagrams of these optical isomers · know that optical activity is the ability of a single optical isomer to rotate the plane of polarisation of plane-polarised monochromatic light in molecules containing a single chiral centre · know what is meant by the term 'racemic mixture' · be able to use data on optical activity of reactants and products as evidence for SN1 and SN2 mechanisms and addition to carbonyl compounds

Carbonyl Compounds (Aldehydes and Ketones)Sign up

understand the nomenclature of aldehydes and ketones and be able to draw their structural, displayed and skeletal formulae · understand that aldehydes and ketones: (i) do not form intermolecular hydrogen bonds and this affects their physical properties; (ii) can form hydrogen bonds with water and this affects their solubility · understand the reactions of carbonyl compounds with: (i) Fehling's or Benedict's solution, Tollens' reagent and acidified dichromate(VI) ions (in equations, the oxidising agent can be represented as [O]); (ii) lithium tetrahydridoaluminate(III) (lithium aluminium hydride) in dry ether (ethoxyethane) (in equations, the reducing agent can be represented by [H]); (iii) HCN, in the presence of KCN, as a nucleophilic addition reaction, using curly arrows, relevant lone pairs, dipoles and evidence of optical activity to show the mechanism; (iv) 2,4-dinitrophenylhydrazine (2,4-DNPH), as a qualitative test for the presence of a carbonyl group and to identify a carbonyl compound given data of the melting temperatures of derivatives (the equation for this reaction is not required); (v) iodine in the presence of alkali (the iodoform test)

Carboxylic AcidsSign up

understand the nomenclature of carboxylic acids and be able to draw their structural, displayed and skeletal formulae · understand that hydrogen bonding affects the physical properties of carboxylic acids, in relation to their boiling temperatures and solubility · understand that carboxylic acids can be prepared by the oxidation of alcohols or aldehydes and the hydrolysis of nitriles · understand the reactions of carboxylic acids with: (i) lithium tetrahydridoaluminate(III) (lithium aluminium hydride) in dry ether (ethoxyethane); (ii) bases to produce salts; (iii) phosphorus(V) chloride (phosphorus pentachloride); (iv) alcohols in the presence of an acid catalyst

Carboxylic Acid Derivatives (Acyl Chlorides, Esters, Polyesters)Sign up

understand the nomenclature of acyl chlorides and esters and be able to draw their structural, displayed and skeletal formulae · understand the reactions of acyl chlorides with: (i) water; (ii) alcohols; (iii) concentrated ammonia; (iv) amines · understand the hydrolysis reactions of esters, in acidic and alkaline solution · understand how polyesters, such as terylene, are formed by condensation polymerisation reactions

Spectroscopy and ChromatographySign up

be able to use data from mass spectra to: (i) suggest possible structures of a simple organic compound given accurate relative molecular masses; (ii) calculate the accurate relative molecular mass of a compound, given accurate relative atomic masses to four decimal places · understand that carbon-13, (13C) NMR spectroscopy provides information about the positions of 13C atoms in a molecule · be able to use data from 13C NMR spectroscopy to: (i) predict the different environments for carbon atoms present in a molecule, given values of chemical shift, delta; (ii) justify the number of peaks present in a 13C NMR spectrum in terms of the number of carbon atoms in different environments · be able to use both low and high resolution proton NMR spectroscopy to: (i) predict the different types of proton present in a molecule, given values of chemical shift, delta; (ii) relate relative peak areas, or ratio number of protons, to the relative numbers of 1H atoms in different environments; (iii) deduce the splitting patterns of adjacent, non-equivalent protons using the (n+1) rule and hence suggest the possible structures for a molecule; (iv) predict the chemical shifts and splitting patterns of the 1H atoms in a given molecule · know that chromatography separates components of a mixture using a mobile phase and a stationary phase · be able to calculate Rf values from one-way chromatograms in paper and thin-layer chromatography (TLC) and understand reasons for differences in Rf values · know that high-performance liquid chromatography, HPLC, and gas chromatography, GC, are types of column chromatography that separate substances because of different retention times in the column and may be used in conjunction with mass spectrometry, in applications such as forensics or drug testing in sport