Organic Chemistry - introduction - Vladimíra Kvasnicová

Composition of Matter inorganic mater  oxygen (O) 50%  silicon (Si) 25%  aluminium (Al) 7%  iron (Fe) 5%  calcium (Ca) 3% 90%  sodium (Na)  potassium (K)  magnesium (Mg)  hydrogen (H)  titanium (Ti) 0,6% organic mater „compounds of carbon“ C, O, H, N  carbon (C)  oxygen (O)  hydrogen (H)  nitrogen (N)  phosphorus (P)  sulfur (S)

Organic compounds „compounds of carbon“ hydrocarbon skeleton: C, H (linear / branched / cyclic)  saturated: CH 3 -(CH 2 ) n -CH 3  unsaturated: -CH=CH- or –C=C- heteroatoms: O, N, S, halogens  heterocyclic compounds  hydrocarbon derivatives (in functional groups) aliphatic or aromatic compounds

Valence of elements in organic compounds CARBONalways tetravalent NITROGENtrivalent OXYGENbivalent SULPHURbivalent HYDROGENmonovalent HALOGENSmonovalent

Types of bonds: 1) single (-ane)  saturated hydrocarbons 2) double (-ene) or triple (-yne)  unsaturated hydrocarbons 3) conjugated (planar cycle: arens)

Shape of molecules σ-bond C-C π-bond C=C C≡CC≡C Alkanes –hybridization sp 3 – tetrahedral shape (4  bonds) ethane

Alkenes –hybridization sp 2 – trigon (3  and 1  ) Alkynes –hybridization sp – linear (2  and 2  ) ethene ethyne

inorganic compoundsorganic compounds high melting pointslow melting points most inorganic compounds are soluble in water most organic compounds are insoluble in water not soluble in organic liquidsare soluble in organic liquids most inorganic compounds conduct an electric current don´t conduct electricity met-et-prop-but-pent-hex-hept-oct-non-dec

Chemical properties hydrocarbons are hydrophobic (= lipophilic) because are nonpolar hydrocarbon derivatives: polar functional group + nonpolar tail reactivity:  multiple bonds  functional groups complete oxidation (= burning) of a hydrocarbon skeleton → CO 2 + H 2 O

Important chemical reactions of organic compounds 1.substitution (= replacement) CH 4 + Cl 2 → CH 3 Cl + HCl 2.addition (multiplicity of chemical bond is lowered) CH 2 =CH 2 + H 2 O → CH 3 -CH 2 -OH 3.elimination (new multiple bond is often formed, small molecule is released) CH 3 -CH 2 -OH → CH 2 =CH 2 + H 2 O 4.rearrangement (= formation of an isomer) CH 2 =C(OH)-COOH → CH 3 -C(O)-COOH

Hydrocarbon rests (alkyls, R) CH 4 → CH 3 - → -CH 2 - methanemethyl methylene CH 3 -CH 3 → CH 3 -CH 2 - → -CH 2 -CH 2 - ethane ethyl ethylene CH 2 =CH 2 → CH 2 =CH- → -CH=CH- ethenevinyl vinylene („ethylene“)(ethenyl)

Aromatic compounds delocalization of π-elektrons more resonance structures planar molecules Hűckel rule: 4n + 2 = number of  -electrons n = 1, 2, 3,...

Aromatic hydrocarbons (= arenes) === = benzene = naphthalene = = = anthracene

== = phenanthrene = = pyrene = benzopyrene

Hydrocarbon rests of arenes (aryls, Ar) →=== = benzenephenyl = biphenyl → toluenebenzyl → benzoic acid benzoyl

Important derivatives of benzene methylbenzene = toluene dimethylbenzenes = xylenes (o-, m-, p-)  1,2-dimethylbenzene = o-xylene  1,3-dimethylbenzene = m-xylene  1,4-dimethylbenzene = p-xylene vinylbenzene = styrene ( → polystyrene, PS)

Exercise - add names of the compounds: 1.CH 3 -CH 2 -CH 2 -CH 3 2.CH 3 -CH 2 -CH=CH-CH 3 3.CH 2 =CH 2 4.CH 3 -CH 2 -CH 2 -CH 2 -C=CH 5.CH 3 -(CH 2 ) 10 -CH 3 butane pent-2-ene ethene hex-1-yne dodecane

DERIVATIVES OF HYDROCARBONS principal functional group  type of the derivative  suffix other functional groups → expressed by special prefixes + locants The name of the compound is derived from the name of the basic unbranched hydrocarbon

meth-eth-prop-but-pent-hex-hept- monoditritetrapentahexahepta oct-non-dec- undec - dodec - tridec - icosa- octanonadeca Number of carbons / number of multiple bonds or functional groups

derivativeformulaprefixsuffix carboxylic acid - COOH carboxy--oic acid sulfonic acid - SO 3 H sulfo-sulfonic acid aldehyde - CHO formyl--al ketone = CO oxo--one alcohol - OH hydroxy--ol thiol - SH mercapto--thiol amine - NH 2 amino--amine ether - O - R-oxy-ether sulfide - S - R-thio-sulfide halogen der. - F, -Cl, -Br, -I halogen-- nitro der. - NO 2 nitro--

derivativeformulaprefixsuffix carboxylic acid - COOH carboxy- -oic acid sulfonic acid - SO 3 H sulfo-sulfonic acid aldehyde - CHO formyl--al ketone = CO oxo--one alcohol - OH hydroxy- -ol thiol - SH mercapto--thiol amine - NH 2 amino--amine ether - O - R-oxy-ether sulfide - S - R-thio-sulfide halogen der. - F, -Cl, -Br, -I halogen-- nitro der. - NO 2 nitro--

derivativeformulaprefixsuffix carboxylic acid - COOH carboxy--oic acid sulfonic acid - SO 3 H sulfo-sulfonic acid aldehyde - CHO formyl--al ketone = CO oxo--one alcohol - OH hydroxy- -ol thiol - SH mercapto--thiol amine - NH 2 amino- -amine ether - O - R-oxy-ether sulfide - S - R-thio-sulfide halogen der. - F, -Cl, -Br, -I halogen-- nitro der. - NO 2 nitro--