05/2 Flashcards
what are the three ways to hydrate an alkene
Acid-catalyzed hydration (markovnikov, no stereoselectivity)
Oxymercuration demercuration (markovnikov, anti addition)
Hydroboration oxidation (anti-markovnikov, syn addition)
How do you create an alkyl halide from an alkene
halogenation (markovnikov addition, no stereoselectivity)
halogenation in peroxides (anti markovnikov, no stereoselectivity)
what is 1,2 dihydroxylation
it is addition of two hydroxyl’s with osmium tetraoxide in pyridine solvent
draw the structure of pyridine
why do we use pryidine in 1,2 dihydroxylation
it is one of the only solvents that dissolves osmium
What is the purpose of reactions, specifically what is the purpose of 1,2 dihydroxylation?
reactions are meant to add functionality, in this reaction we add 2 hydroxyls
what are the important features of a 1,2-dihydroxylation with OsO4 as a reagent?
it is a syn addition that adds two hydroxyl groups on neighboring carbons on the same side
why do we prefer to use catalytic dihydroxylation?
it uses less Osmium, which is toxic
if we wanted to preform catalytic dihydroxylation, what solvent should we use?
NMO, n-methyl morpholine oxide
what is the purpose of using Ozone (O3) with an alkene
oxidative cleavage of an alkene, it creates a open chain alkane with added oxygens
how is O3 created
with an ozenator, it electrically charges an O2 to create O3
If you have a cycloalkene with only hydrogens attached at the pi bond, what is the product with an O3 reagent
a dialdehyde
what is the process of a oxidative cleavage of alkenes?
we take ozone (O3)/Me2S to a cycloalkene, the oxygens create carbonyls at the carbons attached to the alkenes, and it opens the ring into a straight chain
depending on the substituents you will get different products
If you have a cycloalkene with methyl substituents on the pi bond, what is the product with an O3 reagent?
diketone
if you preform oxidative cleavage with KMnO4 and a nonsubstituted alkene, what is the product?
dicarboxylic acid
when subjected to O3/Me2S, Alkenes with mono carbon atoms are oxidatively cleaved to
dialdehyde
when subjected to O3/Me2S, Alkenes with disub carbon atoms are oxidatively cleaved to
diketones
when subjected to KMnO4, Alkenes with monosub carbon atoms in basic conditions are oxidatively cleaved to
carboxlylic acids
if we subject a terminal alkyne to an excess halogen, what is the result
tetrahalo compound
when preforming a hydrohalogenation to an alkyne, where do we add the halogen?
it is a markovnikov addition, so we add the halogen to the more substituted carbon
when preforming hydrohalogenation on a terminal alkyne, what is the end result
a geminal dihalide
when reacting HBr in peroxides with an alkyne , what is the result? where will the Br add?
we will get both cis and trans alkene structures with the Br on the less substituted carbon
what is a radical?
a radical carbon has 3 bonds and 1 electron, it is neutral
what is the least stable intermediate
radicals
