Title Introduction to Organic Chemistry.pdf ✅

1 H2 Chemistry Introduction to Organic Chemistry & Isomerism Notes Name:__________________________________________________________________ Learning Outcome: Candidates should be able to: (a) interpret, and use the nomenclature, general formulae and displayed formulae of the following classes of compound: (i) hydrocarbons (alkanes, alkenes and arenes) (ii) halogen derivatives (halogenoalkanes and halogenoarenes) (iii) hydroxyl compounds (alcohols and phenols) (iv) carbonyl compounds (aldehydes and ketones) (v) carboxylic acids and derivatives (acyl chlorides and esters) (vi) nitrogen compounds (amines, amides, amino acids and nitriles) (b) interpret, and use the following terminology associated with organic reactions: (i) functional group (ii) degree of substitution: primary, secondary, tertiary, quaternary (iii) homolytic and heterolytic fission (iv) carbocation (v) free radical, initiation, propagation, termination (vi) electrophile (Lewis acid), nucleophile (Lewis base) (vii) addition, substitution, elimination, condensation, hydrolysis (viii) oxidation and reduction [in equations for organic redox reactions, the symbols [O] and [H] are acceptable] (c) describe sp3 hybridisation, as in ethane molecule, sp2 hybridisation, as in ethene and benzene molecules, and sp hybridisation, as in ethyne molecule (d) explain the shapes of, and bond angles in, the ethane, ethene, benzene, and ethyne molecules in relation to σ and π carbon-carbon bonds (e) predict the shapes of, and bond angles in, molecules analogous to those specified in (d) (f) apply (b) to the understanding of mechanisms in terms of organic structure and bonding (more will be covered in the subsequent organic topics) (g) describe constitutional (structural) isomerism

3 1 Introduction Organic chemistry is the chemistry of the compounds of carbon and hydrogen (with the exception of CO, CO2, CS2 and various bicarbonates, carbonates and cyanides which are considered to be inorganic). Many such compounds are found in living plants and animals, and that is the origin of the term “organic”. It is essential to learn about the structure of the carbon atom and how it covalently bonded with hydrogen and other elements that build up the vast family of organic compounds. 2 Hybridization & Shape of Organic Molecules 2.1 Introduction to Hybridisation • However, ground state electronic configuration of a carbon atom suggests that it should only form two covalent σ-bonds because it only has two unpaired electrons available to pair with the electrons from hydrogen atoms. Hence the simple theory of sharing of electrons using half-filled atomic orbitals is insufficient to explain the existence of four covalent bonds per carbon atom. A new theory is this required to explain the above observation.