Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
21 Cards in this Set
- Front
- Back
- 3rd side (hint)
|
mCBA ,(CHCl3)
|
epoxide from alkene, syn addition (racemic)
|
|
|
|
KOH, alc
|
primary double bond from primary halide or alkene from halide;
KOH always elimination |
|
|
|
Cl2, CCl4
|
dicloro from double bond, anti
|
|
|
|
DMF solvent (aprotic)
|
SN2 adds to smaller molecules together
|
|
|
|
dry ether
|
OMgBr from carbonyl + MgBr
|
|
|
|
NaOCH2CH3
|
ether(in middle)from primary halogen
|
|
|
|
HCl, ZnCl2
|
primary Cl from OH; complete substitution
|
|
|
|
1)NaNH2
2)CH3CH2I, DMF |
reduced to alkene and added
CH3CH2(w/o the I) to less substituted C |
|
|
|
C=O bonds
|
O is more electronegative and is electron rich; carbonyl os strongly polorized;addition follows nucleophile to C;electrophile to O
|
|
|
|
How acidity increases
|
H2O>ROH>RC(triple)CH>NH3>CH4
|
|
|
|
weaker acid on left
|
No reaction b/c rxn goes to left
|
|
|
|
Retrosynthesis (working backwards) Steps
|
Look for ways to break up molecule
1.Identify functional group in the compound to be sythysized 2.How is that functional group formed? 3.choose best method the one with the best yield. 4.write the chemical equation with the specific compounds that under go the reaction to form the desired product. 5.repeat until the reactants are the permitted starting materials. |
The most effective synthysis is the ones with the fewest steps with the hightest possible yield. If ether use grinard reagent
|
|
|
3 features of SN rxns at sp3
|
1)sp3 hybrid carbon atom
2)leaving group 3)nucleophile |
|
|
|
Common leaving groups
|
Halogen atoms;ArSO3(arene sulfonates); NR3+ (amonium ions);SR2(alkyl sulfonium ions
|
|
|
|
common nucleophiles
|
1)mostly neg charge (OH-,CN-
2)neutral (I,NH3,H20,and alcohols) all have at least on pair of electrons to form bond with sp3 C atom |
|
|
|
nature of leaving group
|
decreasing base strength generally increase the rate, the less basic the leaving group the more easily it leaves
|
|
|
|
SN1 reactions usually
|
will form a carbocation; is only option with tertiary;for secondaary compounds, when leaving group is good;nucleophile is weak;solvent is polar
|
|
|
|
SN2 rxns
|
nucleophile is very good;polar aprotic solvent; support backside approach
|
|
|
|
KOAc, DMF
|
OAc replaces halogen from back side;SN2 b/c weak base
|
|
|
|
1)O3
2)H2O, Zn |
cleaves double bond alkene to form carbonyl; ?forms ide & ozonide?
|
|
|
|
TsCl or AcCl, pyr
|
Ts or Ac replaces H of alcohol (O remains)
|
|
