Organic Chemistry Flashcards
determining R/S
lowest in back, determine direction
Fischer – ignore #4, determine direciton, flip to its opposite (R>S, S>R)
polar protic solvent on nucleophiles
nucleophiles stronger DOWN periodic table
polar aprotic solvent on nucleophiles
nucleophiles stronger UP periodic table
phenols
OH groups on aromatic ring
H is very acidic due to resonance stabilization of O-
1° OH –> aldehyde
PCC ONLY
rare
1° OH –> COOH
most strong OA’s
2° OH –> ketone
PCC
or STRONG OA
mesylate/tosylates
make OH groups on alcohols better LG’s
protect OH groups because they don’t react
acetal vs hemiacetal
hemiacetal = RO-C-OH
acetal = RO-C-OR
make by adding 1 or 2 alcohols (-OR)
stabilization of C-
EWG stabilize -
EDG destabilize -
(opposite for C+?)
michael addition
form C-C bonds!
1. base deprotonates alpha carbon, enol–enolate ion
2. enolate ion (Nuc) attacks alpha-beta unsaturated C=C bond, bonds NEW C-C
claisen condensation
form new C-C bond
occurs between 2 esters or cabonyl-containing compounds
makes a beta-keto ester (ester + another C=O on B-carbon)
more stable conjugate base = stronger acid
EWG stabilize conjugate base and increase acidity
EDG destabilize conjugate base and lower acidity
reactivity: carbox acid derivatives
anhydrides > esters = carbox acid > amides
all derivatives formed by condensation rxn with COOH and nucleophile
amides
nuc. acyl sub with COOH + amine/ammonia
cannot occur with tertiary amines
cyclic amides = lactams