12/5 Flashcards
What are the reactants for a claisen condensation
two esters under basic conditions
what is the product of a claisen condensation
beta keto ester
which way does equillibrium lie for the first step of claisen condensation
it favors the reactants
at what step does claisen condensation become favorable
deprotonation of the beta keto acid to form the weaker ethanol acid
when is a crossed claisen condensation possible
when one ester components does not have ANY alpha hydrogens
what is the enolate and what is the electrophile in a crossed claisen
the ester with no alpha hydrogens is the electrophile and the ester with the alpha hydrogen will form the reactive enolate
what happens if you try to do a claisen condensation with two esters that both have alpha hydrogens
a mixture of products
if you react two ketones or aldehydes under acidic or basic conditions what is the result with no heat
you get the aldol product with a ketone/aldehyde with an alchohol
if you react two ketones or aldehydes under acidic or basic conditions under heat what is the result
you get a dehydrated product which is the alpha-beta unsaturated aldehyde or ketone
what reagents favor 1,2 addition with alpha beta unsaturated ketones
grignard
what reagents favor 1,4 addition with alpha beta unsaturated ketones
Gilman (Ch3)2 Cu Li
HCN
beta ketones
RS
amines
enamines
for addition of 1,3 butadiene, what conditions favor kinetic
no heat, -60 C, faster forming
for addition of 1,3 butadiene, what conditions favor thermodynamic product
heat, more stable product most substituted
which product has lower energy, the thermodynamic or kinetic product of 1,3 buradiene
the thermodynamic product takes more energy to form but is lower energy overall
what are environmentally harmful solvents?
nonpolar solvents (benzene, halogens, DMF)
