OF ALDEHYDE

Place 160 gm of grease and rust free iron filings, 300 ml glacial acetic acid and 300 ml of water in a 2-litre round-bottom flask. Add 50 ml of freshly distilled n-heptaldehyde into the stirred mixture. Heat the mixture, so that the frothing is under control, for 4 hours.

Steam distill for the n-heptyl alcohol produced (ca 2 litres of distillate). Isolate the organic portion. Heat it with 100 ml of 20% sodium hydroxide for 2 hours with strong stirring (to hydrolyse any ester present). Isolate the alcohol and dry over anhydrous calcium sulphate. Distill for the n-heptanol at 174 - 176˚C. Yield = 75%.

n-Heptanal: M. Wt. = 114.2; B.Pt. = 154�C; B.Pt.(11mmHg) = 40�C; and density = 0.818 g ml‾�. n-Heptanol: M.Wt = 116.2; B.Pt. = 174�C; and density = 0.822 g ml‾�.

OF KETONE

Place 50 ml of methyl pentyl ketone, 100 ml (95%) ethanol, and 30 ml of water in a 1 litre round-botton flask. Add 24 gm of fresh sodium wire in portions to avoid too vigorous a reaction. Keep the mixture at ca 30˚C with ice.

When the sodium has completely reacted, carefully add 350 ml of water keeping the temperature below 30˚C. Isolate the organic portion and wash it with dilute HCl acid, then water, and dry with anhydrous potassium carbonate. Distill for the 2-heptanol at 156 - 158˚C. Yield = 60%.

2-Heptanone: M. Wt. = 114.2; B.Pt. = 149�C; and density = 0.815 g ml‾�. 2-Heptanol: M.Wt = 116.2; B.Pt. = 158�C; and density = 0.818 g ml‾�.

OXIDATION

OF ALCOHOL

Add 50 g of sodium dichromate dihydrate into 60 ml of 5M sulphuric acid in a 1 litre round bottom flask. Cool the mixture to room temperature. Stir the mixture and add 40 ml of 4-ethylcyclohexanol keeping the temperature low by an ice-bath. Stir for 3 hours. Isolate the organic portion, dry and distill. Yield of 4-ethylcyclophexanone = 90%.

4-Ethylcyclohexanol: M. Wt. = 128.2; B.Pt. = 84�C; and density = 0.889 g ml‾�. 4-Ethylcyclophexanone: M.Wt = 126.2; B.Pt. = 193�C; and density = 0.895 g ml‾�.
Sodium dichromate dihydrate: Na₂Cr₂O₇, M. Wt. = 298