EX 9: PHENOLS Flashcards
- organic aromatic compounds wherein the HYDROXYL GROUP IS ATTACHED to a BENZENE RING
- considered as alcohols due to their OH group, however, DIFFER in their CHEMICAL BEHAVIOR
PHENOLS
phenols difference with alcohols technically is due to the _____
PHENYL RING
EPINEPHRINE, NEPINEPHRINE, DOPAMINE
CATHECOLAMINES
ortho
CATHECOL
micro
RESORCINOL
para
HYDROQUINONE
- TOXIC, COLORLESS CRYSTALLINE solid with SWEET TARRY odor
- usually employed as an ANTISEPTIC and DISINFECTANT
- also used in cosmetic formulations and manufacture of some drugs (precursor)
PHENOLS
Phenols are also known as
hydroxybenzene / carbolic acid
- a surgeon who discovered that patients die due to secondary infections
- he used carbolic acid to wash hands / disinfect before performing the surgery
JOSEPH LISTER
boiling point of phenols
HIGHER than hcs
H-bonds make it possible for the phenol to be __________ to the water
SLIGHTLY SOLUBLE
PHENOLS:
an __________ in the size of the aryl group attached to the hydroxyl group decreases it solubility in water
INCREASE
PHENOLS:
an increase in the size of the ___________ attached to the hydroxyl group decreases it solubility in water
ARYL GROUP
PHENOLS:
an increase in the size of the aryl group attached to the ________ group decreases it solubility in water
HYDROXYL
PHENOLS:
an increase in the size of the aryl group attached to the hydroxyl group ________ it solubility in water
DECREASES
PHENOLS:
an increase in the size of the aryl group attached to the hydroxyl group decreases it _______ in water
SOLUBILITY
the reaction of phenols with active metals form _______
PHENOXIDES
phenol attached to a metal
PHENOXIDES
PHENOLS:
sp2 hybridized C of the benzene ring attached to the OH group functions as an
ELECTRON WITHDRAWING GROUP
due to the DELOCALIZATION of the electrons in the benzene ring, phenoxide ions are _________
MORE STABLE
_____ are MORE AICDIC than alcohols
PHENOLS
in substituted phenols, its acidity ________ if an electron donating group is attached to the ring and vice versa
DECREASES
diazotization of primary aromatic amines
SYNTHESIS OF PHENOLS
benzene diazonium chloride is formed when a primary aromatic amine with nitrous acid (NaNO2 + HCl) at
~5°C,
primary aromatic amine with nitrous acid (NaNO2 + HCl) at ~5°C forms __________
benzene diazonium chloride
these diazonium salts are _________ and upon warming with water, will be
hydrolyzed in to phenol
HIGHLY REACTIVE
these diazonium salts are highly reactive and upon warming with water, will be
hydrolyzed in to _______
PHENOL
identify SOLUBILITY of phenols
SOLUBILITY TEST
SOLUBILITY TEST:
phenols react with dilute aqueous sodium hydroxide to form ______________ (more soluble with water compared to phenol due to its phenyl ring)
SODIUM PHENOXIDE
SOLUBILITY TEST:
phenol in 5% NaOH
SOLUBLE; CLEAR DARK BROWN TO BLACK SOLN
can detect the presence of PHENOLIC COMPOUNDS
RXN W/ FERRIC CHLORIDE
RXN W FERRIC CHLORDE:
POSITIVE RESULT
COLORED COMPLEXES
RXN W/ FERRIC CHLORIDE:
formation of __________ that absorbs visible light to give an excited state in which electrons are delocalized over both the iron atom and the conjugated organic system
FERRIC PHENOXIDE
RXN W/ FERRIC CHLORIDE:
formation of ferric phenoxide that absorbs _________ to give an excited state in which electrons are delocalized over both the iron atom and the conjugated organic system
VISIBLE LIGHT
can be used to identify PHENOLICS (however, other compounds may also yield positive results)
BROMINE WATER TEST
BROMINE WATER TEST:
POSITIVE RESULT
CLEAR COLORLESS SOLN W/ WHITE PPT
BROMINE WATER TEST:
bromination of phenol results to _______________ product which appears as white precipitate while the side product of hydrobromic acid results to decolorization of the solution with an odor of an antiseptic
2,4,6-TRIBROMOPHENOL
BROMINE WATER TEST:
bromination of phenol results to 2,4,6-tribromophenol product which appears as _________ while the side product of hydrobromic acid results to decolorization of the solution with an odor of an antiseptic
WHITE PPT
BROMINE WATER TEST:
bromination of phenol results to 2,4,6-tribromophenol product which appears as white precipitate while the side product of ___________ results to decolorization of the solution with an odor of an antiseptic
HYDROBROMIC ACID
BROMINE WATER TEST:
bromination of phenol results to 2,4,6-tribromophenol product which appears as white precipitate while the side product of hydrobromic acid results to decolorization of the solution with an odor of an ________
ANTISEPTIC
FORMATION OF PHENOLPHTHALEIN:
phenol can also be used as _________ in the synthesis of several organic compounds
PRECURSOR
FORMATION OF PHENOLPHTHALEIN:
phenol reacts with ___________ under an acid catalyst using an electrophilic aromatic substitution reaction
PHTHALIC ANHYDRIDE
FORMATION OF PHENOLPHTHALEIN:
phenol reacts with phthalic anhydride under an acid catalyst using an ____________________ reaction
ELECTROPHILIC AROMATIC SUBSTITUTION
FORMATION OF PHENOLPHTHALEIN:
color in ACIDIC soln
COLORLESS
FORMATION OF PHENOLPHTHALEIN:
color in BASIC soln
PINK TO MAGENTA
determine the presence of phenolic compounds in AMINO ACIDS
MILLON’S TEST
Millon’s reagent
HgNO3 (mercurous nitrate) & Hg(NO3)2 (mercuric nitrate) in HNO3 (nitric acid)
MILLON’S TEST:
POSITIVE RESULT
RED PPT
the only amino acid with phenol in its structure
TYROSINE
MILLON’S TEST:
amino acids and proteins with phenol radicals react with Millon’s reagent to form _______________
RED COLORED SOLN
