24 Cards in this Set
| Front | Back |
|---|---|
|
What are the different ways to synthesize aldehydes and ketones
|
1. oxidation of alcohol, PCC, jones, MnO2
2.Ozonolysis
3. Markovnikov hydration of alkynes
4.Hydroboration of alkynes
|
|
polarization of carbonyl functional group
|
makes aldehydes and ketones have a higher boiling point, are also more miscible in water
|
|
there are three different regions of reactivity in aldehydes and ketones
|
the oxygen is attacked by electrophiles
the carbon double bonded to the oxygen is attacked by nucleophiles
|
|
strong bases as nucelophiles
|
makes the reaction irreversible
|
|
acetalization
|
equlibrium reaction, thermodynamically driven
driving forces: excess EtOH, remove H2O w drying agent
|
|
what is the difference between an acetal and an ether
|
you can do this with aldehydes and ketones but not acids or esters
doing this with cyclic molecules gives you diols
|
|
what happens when you acetalize a diol
|
you get a cyclic acetal
|
|
what are the applications of acetalization
|
bugs - reeversible formation is important
powerful pheromones
used as protective groups in synthesis because they can formed reversibly
|
|
rules with bisulfite adduct reactions
|
must use cyclic ketone or aldehyde, doesn't work with acyclic ketones.
used for extractions
|
|
ylide
|
a negatively charged carbon atom is attached to a positively charged heterotatom
|
|
bayer villager oxidation: migratory aptitudes
|
me< 1o <2o <3o
|
|
keto enol tautomerism
|
equalibrium strongly prefers keto over enol form but the enol form can be stabilized by H bonding and additional delocalization
|
|
dean-stark
|
technique removes water as an aziotrope
|
|
alkylation of enolates
|
if limiting amounts of MeI are used, a poly alkylation occurs.
Doing an irreversible deprotonation means one final product and higher yield of said product
|
|
Problems with enolate equlibration
|
can react as a base and deprotonate the product
|
|
aldols
|
reactions are reversible
|
|
non enolizable aldehyde
|
an aldehyde with no alpha hydrogens (alpha hydrogens bond to alpha carbons- carbon bonded to functional group)
|
|
amides
|
amide bonds are quite stable, mroe stable than esters, acid chlorides and anhydrides but less stable than
|
|
alkylation
|
a great way to form a ketone
|
|
alodol condensation
|
useful because it combines two carbon carbon groups and leaves an aldehyde/ketone
|
|
formic acid
|
planar
|
|
carboxylic acids
|
the carboxyl group is polar, form dimer readily, lose hydrogens readily
|
|
addition-elimination reaction
|
eliminating the leaving group and replacing it with the nucleophile
|
|
tetrahedral intermediate
|
the first species formed after an addition - elimination reaction
catalyzed by acid base
the acid first protonates the carbonyl oxygen, the second protonation make the leaving group a better leaving group
|
CHEM 0320: Notes