synthesis and structural elucidation

1. D. Jim Livingston
Asst. Prof. of Chemistry
St. John’s College.
STRUCTURAL ELUCIDATION AND SYNTHESIS

2.  INTRODUCTION
 EXTRACTION
 EFFECT OF NICOTINE
 PROPERTIES
 STRUCTURAL ELUCIDATION
 SYNTHESIS
 REFERENCES

3. Nicotine is a stimulant alkaloid that is naturally
obtained from tobacco plants.
Both the tobacco plant (Nicotiana tabacum) and the
compound are named after Jean Nicot, a French
ambassador, who sent tobacco seeds to Paris in 1560.
Nicotine is one of the few liquid alkaloids
Nicotine is the chief addictive ingredient in the
tobacco used in cigarettes, cigars, and snuff
INTRODUCTION

4. Powdered tobacco leaves extracted with dil. acid
Extract is treated with sodium hydroxide and steam distilled
Treated with oxalic acid to make it a PH of 3.0, concentrated and cooled
Crystal is treated with excess KOH, and extracted with ether.
Filtered, and dried.
Water soluble salts are removed
Non-volatile materials are eliminated
Crystals of salts of nicotine and oxalic acid
Nicotine separates as brown oil.
EXTRACTION OF NICOTINE

6. Molecular weight: 162.26
Nicotine is a liquid alkaloid.
Soluble in water
bitter in taste
strongly alkaline in reaction and
forms salts with acids.
PROPERTIES OF NICOTINE

7. Molecular Formula : C10H14N2
 No oxygen, hence it should be an amine
 No benzoyl derivative and reacts with two
molecules of CH3I Both N are tertiary
 Heating with HI gives one molecule of CH3I
one N-CH3 group
STRUCTURE OF NICOTINE
Herzig – Meyer method

8.  Oxidation Reaction:
With KMnO4 it gives Nicotinic acid
(pyridine-3-carboxylic acid)
STRUCTURE OF NICOTINE
Pyridine nucleus with side chain at 3rd position

9. STRUCTURE OF NICOTINE

10.  Distillation with zinc chloride:
It forms an addition compound with ZnCl2
which on distillati0n gives pyridine, pyrrole
and methylamine
pyridine
pyrrole
side chain at 3rd position must be pyrrole derivative
STRUCTURE OF NICOTINE

11.  Hydrogenation:
Only three moles of H2 are added.
side chain is fully saturated
 It has N-CH3 group
 pyrrole has 4 hydrogens but the side chain needs 7 hydrogens
side chain is a pyrrolidine derivative
STRUCTURE OF NICOTINE

12.  Conversion of nicotine to Hygrinic acid:
warmed with methyl iodide, oxidized with
potassium ferricyanide Nicotone.
Further oxidation with CrO3 gives hygrinic acid
STRUCTURE OF NICOTINE

13. MECHANISM
STRUCTURE OF NICOTINE

14. STRUCTURE OF NICOTINE

15. SYNTHESIS OF NICOTINE
Spath and Bretschneider - 1928

16. SYNTHESIS OF NICOTINE
Craig - 1933

17. REFERENCES