PLEASE NOTE THAT SECTIONS OF THIS ARE STILL BEING COMPLETED.
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prepare benzaldehyde by the oxidation of benzyl alcohol by dilute, aqueous nitric acid with sodium nitrite present.
for every 1 mole of benzyl alcohol oxidation, 0.5 of a mole of nitric acid is consumed. the initial concentration of sodium nitrite doesn't affect the progress of the
reaction but its presence is necessary
for its initiation.
these reactants should be combined into a FBF with stirring beads atop of a heating plate.
the energy required for benzyl alcohol to be oxidised by the nitric acid is 81.85kJ/mol. this will form the intermediate benzyl nitrite which is changed to benzaldehyde at
an energy of 94.62kJ/mol.
other products formed are N2O, and water.
1 mole of benzaldehyde and 1.06 sodium bisulfite are vigorously agitated in a vessel with 500ml of water until the formation of the addition compound was complete.
1.10 mole of nitroethane was dissolved in a solution of 1.125 mole of sodium hydroxide dissolved in 200ml of water.
this solution was gradually added with agitation and at room temperature to the addition product of benzaldehyde and sodium bisulfite.
after stirring this for half of one hour, it was allowed to stand overnight. the lower layer was then discarded and the upper layer was dissolved in ether and washed with
sodium bisulfite solution.
the ethereal solution was dried over calcium sulphate and after removal of the ether it was distilled. the BP was between 120-130C.
this 2-nitro-1-phenyl-1-propanol then has to be reduced to 2-amino-1-phenyl-1-propanol.
a mixture of 2-nitro-1-phenyl-1-propanol (36.2 g, 0.2 mole), 100 mL of absolute alcohol, and 4 g of Raney nickel was placed in a Parr hydrogenation bomb. Sufficient solid
carbon dioxide was added to produce
a pressure of 300 psi, then hydrogen was introduced to bring the total initial pressure to 1800 psi. Approximately four hours was required for complete reduction. On
distilling, N-ethylbenzylamine (5%) and
2-amino-1-phenyl-1-propanol (87%) were obtained. When no carbon dioxide was used, the yield of N-ethylbenzylamine approximated 45%. N-ethylbenzylamine was identified by its
boiling point (198°C) and the
melting point of the hydrochloride (184°C) compared with an authentic sample prepared from benzaldehyde and ethylamine.
producing benzene:
benzene can be readily prepared from the decarboxylation of sodium benzoate with sodium hydroxide, by heating the mixture and condensing the resulting benzene. the
decarboxylation method tends to produce
biphenyl and other side products, giving the condensate an orange or orange-reddish color. this can be removed with a simple distillation, giving crystal clear benzene,
though some traces of water may still
exist.
(TOXIC GAS) preparing the propionic acid:
concentrated (70%) Nitric acid (710g, 500 mL) and 50 mL of water were introduced into a vessel equipped with a mechanical stirrer. n-Propanol (144.5g, 180 mL) were slowly
added over a period of two hours,
while the contents of the vessel were stirred vigorously and cooled to maintain the temperature at 30-35°C. a reflux condenser was attached to the vessel so as to prevent
the loss of low-boiling products
while allowing exhaust fumes, consisting primarily of nitrogen oxides (toxic and irritating!) and carbon dioxide, to escape. propionic acid was obtained in 82.5% yield and
acetic acid in 10.8% yield.
the conversion of the n-propanol was 100%. the reaction products can be separated by distilling off the azeotropic mixture of the aliphatic acid and water from which the
acid can be recovered by solvent
extraction, e.g. with a mixture of benzene and ethyl acetate.
preparing the phosphorous trichloride:
THIS STUFF IS DEADLY TOXIC.
buy it. or use the kornblum modification of the victor meyer reaction.
first produce ethylene:
the alcohol is dehydrated using aluminium oxide as the catalyst.
ethanol vapour is passed over heated aluminium oxide powder as shown in the diagram.
then form the alkyl halide:
in hydrohalogenation the ethylene reacts with hcl to form the alkyl halide.
bubble the ethylene gas through the hcl.
the production of the nitroethane from the alkyl halide, sodium nitrite, and dimethyl sulfoxide:
to be finished...
prepare ethyl iodide:
A mixture of 500 g (3.94 mol) of iodine, 800 mL of 84% (w/v) ethanol, and 60 g (2.224 mol) of aluminum foil in small pieces is warmed gently. Once started, the reaction
increases progressively in vigor,
but can be controlled by cooling; it subsides in about 10 min, and is complete in an hour. The product is distilled until deep red fumes appear. A cold mixture of 700 mL of
84% ethanol and 400 mL of 85%
sulfuric acid is added to the cooled residue. After 15 min, distillation is begun, and continued until no more oily drops form in the water in the receiver. The yield of
crude ethyl iodide is 260 mL
(504 g; approx. 80% yield).
prepare silver nitrite:
Silver nitrite is produced from the reaction between silver nitrate and an alkali nitrite, such as sodium nitrite. Silver nitrite is much less soluble in water than silver
nitrate, and a solution of
silver nitrate will readily precipitate silver nitrite upon addition of sodium nitrite.
preparing the nitroethane:
Ethyl iodide (3.12g, .02 mole) freshly distilled was stirred in an ice bath at 0'C. Small portions of dry AgNO2 (3.08g., .02 mole) prepared as described (579) were dropped
in. The internal temperature
rose to 16'C. The reaction mixture was left overnight (12 hr.) in a cold water bath at 15'C and distilled at atmospheric pressure (739 mm). First fraction (70-75'C) (ethyl
iodide 1.84g) and second
fraction (108-115'C), (nitroethane, 570mg) were collected.
potassium cyanate is prepared by heating urea with potassium carbonate at 400C.
5 grams of phenylpropanolamine hcl is placed into a 100ml FBF and 3 grams of potassium cyanate and 25ml of distilled water was added immediately in succession.
this is heated to reflux on a hot plate for two hours and then 30ml of 2M hcl is added.
reflux was then continued for an additional two and a half hours and the mixture was then basified with sodium carbonate. crystals will precipitate out of the solution.
