570 likes | 1.03k Views
Fragrance Chemicals. Chemical Types. Alcohols Aldehydes & Ketones Aliphatic & Aromatic Esters Terpenes Phenols Nitriles Lactones Heterocyclics Acids Sulphur compounds. Hydrocarbons. Mild, Sweet, Warm. Woody Spicy. Caryphyllene. Beta Farnesene. Esters.
E N D
Fragrance Chemicals
Chemical Types • Alcohols • Aldehydes & Ketones • Aliphatic & Aromatic Esters • Terpenes • Phenols • Nitriles • Lactones • Heterocyclics • Acids • Sulphur compounds
Hydrocarbons Mild, Sweet, Warm Woody Spicy Caryphyllene Beta Farnesene
Esters O II R-OH + R’COOH R-C-O-R’ Hydrolyze at high and low pH, acid product may precipitate
OH Alcohols R-OH Aliphatic Aromatic
Aldehydes & Ketones H C=O R Aldehyde Ketone R’ C=O R
“Aldehydes” The so-called aldehydes C14, C16, and C18 are not really aldehydes. the confusion came from the original manufacturers to conceal their identity.
Aldehyde C14, So-called O O Peach
Aldehyde C16, So-called O O O Strawberry
Aldehyde C18, So-called O O Coconut
Terpenes Isoprene Units Joined Head To Tail (C5H8)n C I C=C-C=C
CHO CHO OH OH Five Key Terpenes Isomerization Hydrogenation Oxidation Geraniol & Nerol OH Citronellol Linalool Citral Citronellal
Nomenclature n Name Formula 2 Monoterpene C10H16 3 Sesquiterpene C15H24 4 Diterpene C20H32 6 Triterpene C30H48 8 Tetraterpene C40H64
Acyclic Terpenes -Myrcene
Monocyclic Terpenes Limonene
Bicyclic Terpenes Pinene
Sesquiterpene -Bisabolene
Nitriles R-C=N Aliphatic C=N Aromatic
Geranyl Nitrile N C Banned 2007!
Substitution When a material is banned, must find alternative. For geranyl nitrile, citronellal nitrile (agrunitril) is good in formulas with low level, <2% Perfumery skill is needed for perfecting on a formula-by-formula basis
Lactone A Cyclic Ester • or Hydroxy Acid forms 5 or 6 member ring by intramolecular • esterfication RCHCH2CH2COO-Na+ I OH
O Lactones Coumarin O
Ionones O iso- n- N- or iso- refer to position of alkyl group ,, refer to position of double bond
Acids Acetic CH3COOH Propionic C2H5COOH Butyric C3H7COOH Alkali (NaOH) form salts which can be solid and water-soluble
C((CH)3)3 C((CH)3)3 NO2 NO2 NO2 NO2 CH3 NO2 CH3 CH3 CH3 NO2 C=O I CH3 Nitromusks Musk Xylene Musk Ketone
Polycyclic Musks O Galaxolide
Leopold Ruzicka1887-1976 The Scientist
"For his work on polymethylenes and higher terpenes" Ruzicka received the 1939 Nobel Prize in Chemistry Ruzicka was interested in the large ring ketones civetone and muscone, and showed that they had 17- and 15-membered carbon rings. This was highly novel work at the time, because Adolph von Bayer, a giant of 19th century chemistry had predicted that such rings would be strained and too unstable to exist.
In his work on terpenes, Ruzicka made extensive use of the isoprene rule, first formulated by Otto Wallach in 1887 but largely ignored until Ruzicka recognized its general significance.
Civetone O
OH OMe Derivatives Phenol OMe OMe Anethole Anisole Estragole
Reactions Phenols + NaOH Na salts NaSalt + O2 turns dark. All aromatics with phenolic group react with air, high pH, elevated temperature. Iron and copper will form highly colored complexes.
Vanillin CHO OCH3 OH Phenol
Sulphur Compounds SH S OH O 4-methyl-3-mercapto- 2-pentanone 3-mercapto-1-hexanol Oxford Chemicals
SH Example 1-p-Menthene-8-Thiol
Polar Diluents CH3CHCH2-O-CH2CHCH3 I I OH OH Dipropylene Glycol (DPG) CH3CHCH2OH I OH Propylene Glycol (PG)
Nonpolar Diluents O II C-OCH2CH3 C-OCH2CH3 II O DEP Also Benzyl Benzoate, Dioctyl Adipate
R – C C O n Solubilizers Usually nonionics-ethoxylates, propoxylates
Chemical Reactions Helpful Reactions Part of the natural maturing process Harmful Reactions Occur in isolated perfume oils or in reaction with base environment
Schiff Base Aldehyde + Amine COOCH3 H2N + CHO OH Methyl Anthranilate Hydroxy- Citronellal
Example COOCH3 CH=N + H2O OH Aurantiol
Storage Effects • Elevated Temperatures • UV Radiation • Moisture • Oxidation Accelerate change or deterioration
Autooxidation CHO COOH Benzoic Acid Benzaldehyde
Polymerization Aldehydes can Solidify OH I CH2CH-CHCHO CH2CHO 2 Phenylacetaldehyde
Hemiacetals Aldehyde/Ketone + Alcohol O OH II I I C +- C- OH C O C Loose, reversible Aging of hydroalcoholics
Acetals O 2CH2H5OH O O HO HO Hydroxy Citronellal Hydroxy Citronellal Demethy Acetal
Ester Hydrolysis O O OH -OH Benzyl Alcohol Benzyl Acetate