Br Br CH3 OCH3 -CH3 -OCH3 CH3 OCH3 CH3 ÓCH3 Br Br A C D

Citronellol ((3R)-3,7-dimethyloct-6-en-1-ol, C10H20O) is an organic fragrance found in the oil extracted from lemon grass. a) Name the two functional groups present in the molecule.  b) When a few drops of bromine dissolved in hexane is added to a sample of citronellol the brown colour of the bromine rapidly disappears. i. What type of chemical reaction has occurred? ii. Draw the structure of the product formed. iii. Name the product.  c) The product formed when citronellol is heated with a mixture of potassium dichromate and sulfuric acid gives a yellow/orange precipitate when shaken with Brady’s reagent (2,4-dinitrophenylhydrazine). It also shows a positive result with Fehling’s solution. i. What type of chemical reaction has occurred ? ii. What type of functional group is present in the product?  d) Explain the type of stereoisomerism which may occur in citronellol.

sketch the various conformational isomers of 1,3-dimethylcyclohexane. Indicate the position (axial/equatorial) of each of the methyl groups in each structure.

propose a catalystic cicle