Question

5. Name the following compounds with IUPAC or common name. Indicate istrans clearly when applied (16 marks) obota сненс, 4-ethyl-2,3, 7-trimethyloctane bolodel modo da asins nodi g vid Sorodneblod 0-3 woll- Soos on lowo- Sexols nous h) by glo dat soodul molt bo bobode Solo 6 od tomogos Sibido 4- Isobutyl-5-methyl nohane

Answer 1

Select the longest carbon chain as parent chain. 8 carbon chain is the parent chain. So, use -oct as root word 21 4-ethyl-2,3,7-trimethyloctane The lowest number should be assigned to side chains. So, there are three methyl groups at C2, C3 and C7 one ethyl group at C4 Write these side chains as prefix and in alphabetical order. Hence the IUPAC name of the compound is 4-ethyl-2,3,7-trimethyloctane (b) o Стенанси, CH2CH2CH3 propoxycyclopentane

(c) 3,5-dimethylhex-1-yne (d) The hydrogens at C3 and C4 (double bond) are opposite to each other. So, this is a trans alkene. (trans)-2,6-dimethyloct-3-ene The lowest number should be assigned to unsaturated carbon over side chains. 3-ethyl-5-methylcyclohex-1-ene In this molecule, the configuration is locked. So, no need to mention the configuration.

(f) (trans)-4-(sec-butyl)-3,5-dimethylhept-2-ene (g) oll (trans)-1,3-dimethylcycloheptane 4-isopropyl-5-methylnonane