To learn about Artificial perfumes and flavours.

2. Preparation of methyl anthranilate
Methyl anthranilate is prepared by esterification of anthranilic acid or N-acetylanthranilic acid.
To the round bottom flask fitted with reflux condenser, which is protected from moisture with a
calcium chloride tube

3. , 7 g of anthranilic acid are suspended in 50 ml of dry methyl alcohol. Dry hydrogen
chloride is passed until the solution is saturated and becomes hot, then the reaction mixture
is refluxed for one hour. When the reaction is complete the solution is cooled and
methyl anthranilate hydrochloride crystallizes. The mixture is diluted with 200 ml of water
and made alkaline by the solution of sodium carbonate. The oily methyl anthranilate is
extracted with ether and the extract washed with 5 % sodium carbonate solution, and
then with water. The extract is dried over sodium sulfate and evaporated to small bulk. The
distillation in vacuum and collecting fraction boiling at 135° C (15 mm of Hg), yields a
crystalline mass melting at 24.5° C.

4. Preparation of methyl salicylate
In a 500 ml round-bottomed flask, a mixture of 30.4 g. of salicylic acid (0.2 mole), 70
ml of methyl alcohol, and 7 ml of concentrated sulfuric acid are is placed. A boiling
chip is added, a reflux condenser is attached, and the mixture is boiled gently on the
steam bath for 5-7 hours

5. The condenser is arranged for downward distillation and the excess alcohol is distilled
as long as it comes over easily (the residue should be about one-third to one-half the
original volume). The flask is then cooled well under the tap and the residue is poured
into a separatory funnel and treated with 70 ml of ether, using a part of this to rinse the
flask. The ethereal solution is then washed thoroughly with two 50 ml portions of water
in order to remove most of the unreacted alcohol and the sulfuric acid. The mixture is
then shaken with 50 ml of 10% sodium bicarbonate solution in order to remove the last
traces of sulfuric acid and to separate the ester from any unreacted salicylic acid. The
washing with bicarbonate is repeated until no precipitate of salicylic acid forms on
acidification of the aqueous layer. The ethereal solution is then separated carefully,
poured into a dry flask, and dried with anhydrous magnesium sulfate for at least one-
half hour. The dried solution is filtered into a distilling flask, the vessel being rinsed with
a little ether. The ether is removed by distillation and the distillation of the ester itself is
carried out over a free flame (no gauze). The boiling point of methyl salicylate is 222° C,
so a water-cooled condenser is not only unnecessary but inadvisable, on account of the
danger of cracking the condenser. An air condenser tube is employed for the distillation
procedure. A small fore-run should be collected separately and the main fraction boiling
at 220° C is collected yielding 75-80% of methyl salicylate.

6. Preparation of ethyl cinnamate
To 50 g of ethyl acetate are added 23 g of sodium in the form of wire. The flask is
cooled in ice, and, with slight shaking, 10 g of benzaldehyde are gradually added.
When all the sodium has gone into solution, the flask is set aside for 2 hours, when it
is acidified with dilute acetic acid. The ethyl cinnamate layer which separates is
removed, shaken up with dilute sodium carbonate solution, and dried over calcium
chloride. It is then distilled, the fraction 265-275 ° being retained. The yield of ethyl
cinnamate is 65%; colorless liquid; insoluble in water; b.p. 271° C.

7. Preparation of 1-phenylethanol
15 g of acetophenone are dissolved in 150 g of absolute alcohol, and the whole
warmed on a water bath. 15 g of sodium wire are rapidly added, and when reaction
has ceased, carbon dioxide is passed in until it is no longer absorbed. 350 ml of
water are added and the mixture evaporated on a water bath until nothing further
distils, the alcohol being recovered. The residue is extracted with ether and dried
over potassium carbonate, the etherremoved on a water bath, and the residue
fractionated under reduced pressure, the fraction 97-103 ° at 15 mm. being
retained. Yield 45%. Colourless liquid; slightly soluble in water. b.p. 198° C/760 mm;
b.p. 118° C/40 mm; b.p. 111° C/20 mm; b.p. 100° C/15 mm.

8. Preparation and uses of citronellol
The reduction of the aldehyde and thus the formation of citronellol or nerol /
geraniol is not allowed. The second olefinic double bond must remain intact.

9. vanillin
If you just want to make a few grams, a very convenient laboratory synthesis has
recently been described, involving electrophilic bromination of 4-
hydroxybenzaldehyde, followed by copper-catalysed methoxylation. As far as large-
scale industrial syntheses go, a classic early method starts from eugenol, which
occurs naturally in cloves, nutmeg and cinnamon. This isomerises to isoeugenol in
alkaline solution, and this in turn can be oxidised (by nitrobenzene) to vanillin.

10. coumarin
Coumarin can be prepared in a large variety of ways, but the 1868 procedure
reported by Perkin is in this context the most noteworthy. The Perkin reaction is
applicable to a wide range of substrates, but the primary report describes the
synthesis of coumarin(4) itself, by reaction of the sodium salt of salicylaldehyde (1)
with acetic anhydride (Ac2O). The same route was later also achieved by the
reaction of salicylaldehyde with Ac2O in the presence of fused sodium or potassium
acetate or Et3N. Regardless of the specific conditions, in each case the
reaction between salicylaldehyde and acetic anhydride delivers O-acetyl
salicylaldehyde (2) in a first step. Next, a base catalyzed intramolecular aldol-type
condensation of O-acetyl salicylaldehyde, followed by dehydration delivers the
desired coumarin.

11. Heliotrope

12. Indian Heliotrope is a herb, slightly woody at base, with a long taproot, stem erect,
unbranched or branches few, 30-80 cm tall; leaves alternate or sometimes nearly
opposite, distinctly stalked, leaf-stalks to 5 cm long, blade narrowing into wings on
the leaf-stalk from a somewhat flat base, ovate-deltoid, margin slightly wavy-crisped,
2.5-10 cm long, 1-5 cm wide, pointed (blunt), lateral veins 4-7 pairs. Flowers are born
in a long tapering cluster at branch-ends, tip coiled, axis up to 20 cm long. The
inflorescence uncoils after the central flowers, which are the oldest, mature. The
flowers are arranged on only one side of the inflorescence. Flowers are pale violet
(lilac) with a yellow throat, but fading to dull white, calyx-lobes linear-lanceshaped,
fringed with hairs, 2 mm long; flower-tube 4-5 mm long; petals rounded. Fruit is 3.5
mm long, ovoid, ribbed, separating into 2 nutlets each 2-celled, 3-3.5 mm long.
Indian Heliotrope is found in all tropical world.
Medicinal uses: The plant has been widely used for centuries to treat warts,
inflammations and tumours. Throughout tropical Africa it is used as an analgesic to
ease rheumatic pain, as a diuretic and to treat numerous skin problems including
yaws, urticaria, scabies, ulcers, eczema and impetigo. Throughout the Continent,
there is a wide variation in the plant parts that are used, and also in methods of
preparation and administration. In the Philippines, the plant is chiefly used as a
traditional medicine. The extracted juice from the pounded leaves of the plants is
used on wounds, skin ulcers and furuncles.