(c) Consider the steroid androstane provided below: 3 10 CH3 11 11 H 13 7 H CH3 (i) Draw out the full structure of androstane-3ẞ,11ẞ-diol (ii) Provide a synthetic strategy (including reagents) to access 11ẞ-acetoxyandrostan- 3ẞ-ol from androstane-3ẞ,11ẞ-diol. (iii) Predict which alcohol group of androstane-3ẞ,11ẞ-diol would oxidise faster to provide the corresponding ketone and explain why.

Give reasons for the following :(i) Phenol is more acidic than methanol.(ii) The C—O—H bond angle in alcohols is slightly less than the tetrahedral angle (190°28′).(iii) (CH3)3C—O—CH3 on reaction with HI gives (CH3)3C—I and CH3—OH as the main products and not (CH3)3C—OH and CH3—I.

Draw structural formulas for these ketones. (a) Ethyl isopropyl ketone (b) 2-Chlorocyclohexanone (c) 2,4-Dimethyl-3-pentanone (d) Diisopropyl ketone (e) Acetone (f) 2,5-Dimethylcyclohexanone

How could you convert butanenitrile into the following compounds? Write each step showing the reagents needed. (a) 1-Butanol (b) Butylamine

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.

1.) Give structures for the following compounds: a) 3-t-butyl-5-hydroxybenzenesulfonic acid   b) 1,2-diethylcycloheptanol

Name the following aldehydes and ketones: (a) (b) CH2CH2CHO CH3CH2CCHCH3 CH3 Draw structures corresponding to the following names: (b) 4-Chloropentan-2-one (e) 3-Methylbut-3-enal

Complete the following; give the missing reactants, reagents and products

Phenylethanol can be oxidised to phenylethanal or phenylethanoic acid, depending on the reagents used (both the alcohol and the aldehyde are of interest for their antimicrobial properties, while the acid is used to treat type II hyperammonemia): A (a) (b) (c) CoH,CH,CHO phenylethanal B C6H5CH₂CH₂OHC₂H₂CH₂CO₂H phenylethanol Suggest reagents (shown as A and B in the scheme above) that could be used to carry out the oxidation of the alcohol to the aldehyde and the acid, respectively. C6H5CH₂- Suggest two other syntheses of phenylethanoic acid, in each case indicating the starting materials and other reagents required, but not giving details of mechanism. One of your proposed syntheses must start with a compound which only contains seven carbon atoms (the acid product contains eight carbon atoms). phenylethanoic acid Phenylethanal can be converted to a hydrate in the presence of aqueous acid, though the position of equilibrium is very far to the left: H H+/H₂O OH C6H5CH₂-C-H OH Explain why…

1a）Give structures for the following compounds: a) phenyl isobutyl ether b) ethyl 4-phenylbenzoate c) 3-sec- butylpyridine d) 3-fluoro-3-hexen-2-one