E2P4 Flashcards
(24 cards)
boiling point of alcohol
is higher than alkanes of the same or similar molecular weight due to hydrogen bonding
as molecular weight of alcohol increases
solubility decreases
lower molecular weight alcohols are
miscible (soluble) in water
as the R-group increases in size, the ____ decreases
solubility
branching tends to
increase solubility over linear alcohols of the same molecular weight (isomers)
what is hydrophobic
R groups (decreases water solubility)
hydrophilic
OH group (increases water solubility)
acidity of alcohol vs phenol
-alcohols are acidic as water and undergo slight dissociation
-phenols are more acidic than alcohols
dissociation reaction
R-OH + H2O
<————-
—–>
R-O- + H3O+
equilibrium expression
only applies to dissociation reactions
Ka = [products]/[reactants]
dehydration
-what type of reaction?
-carbon bearing OH must have?
-if all R groups are the same, how many products?
-if 2 R groups are the same out of 3, how many?
-elimination reaction (loss of OH and H)
-carbon bearing OH must have an available H adjacent to it
-1 product will be produced for same R groups
-2 products will be produced for 2 same R groups out of 3
dehydration reaction
alkane with OH
H+
——>
180•C
alkene with HOH
when dehydration produces 2 products
one will be major (more symmetrical) and one will be minor
zaitsev’s rule
the more symmetrical alkene is produced in the greatest abundance
halogenation reaction (no.1: best for 1&2 alc.)
R-OH + SOCl2
——>
R-Cl + HCl + SO2
halogenation (no.2 best for 1&2)
3R-OH + PX3
—->
3R-X + H3PO3 (X= Cl, Br)
halogenation (best for 3 alc)
R-OH + HX
—>
R-X + H2O (X= Cl, Br, I)
oxidation reaction
-is only for what type of ROH?
-the carbon bearing OH must have?
-net effect means?
-reaction
-ONLY 1 & 2, never 3
-H as well
-the removal of two H, one from OH and one from carbon
- alkane with CH and OH
[o]
—>
ketone +H2O
oxidation reactions of alcohols may form
aldehyde , ketone or carboxylic acid
oxidation of primary alcohols
a.
b.
c.
a. gentle oxidation stops at aldehyde
R-CH2-OH
[O]
—->
aldehyde + H2O
b. continued of strong oxidation stops at carboxylic acid
R-CH2-OH
[O]
—>
[O]
—–>
carboxylic acid + H2O
overall reaction
R-CH2-OH
[O]
—–>
aldehyde
[O]
—–>
carboxylic acid + H2O
oxidation of secondary alcohols
-forms?
-forms a ketone
R2CHOH
[O]
—->
ketone + H2O
oxidation of tertiary alcohol
not possible no reaction
phenols:
-have ____melting _____
-____ at room temp.
-soluble in water?
-have low melting solid
-oily liquids at room temp
-slightly soluble in water
