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Acid:
dissociates to give H+
donates H+/proton
e- acceptor
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Base:
dissociates to give OH-
accepts H+/proton
e- donor
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Nucleophile:
- unshared e- pair/ π bond
- - /neg charge
- "nucleus-loving"
- lewis charge
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What makes a good nucleophile?
- stronger -/neg charge, higher nucleophilicity;
- basicity incr so does nucleophicity;
- ↑basicity = ↑nucleophilicity
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Electrophile:
- +/pos charge
- "electron loving"
- lewis acid
- incomplete octet
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INDUCTION:
- sharing e- through covalent b.
- electronegative = electron withdrawing
- not electronegative = electron donating
- * alkyl gr --> electron donating
- (alkyl -- alkane missing one H ; smallest methyl CH3-)
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e- donating gr =
- give e- density to bond
- = more basic = less acidic
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e- withdrawing gr =
- take away e- density from bond
- = less basic = more acidic
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RESONANCE:
- more stable by spreading charge
*delocalization: moving electrons b/w p-orbitals incr stability
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- Rules of Resonance -
- 1. can only go through p orbitals
- 2. can only move through lone pairs or π bonds
- 3. + charges end up on the non-electroneg atoms
- 4. - charges end up on electroneg atoms
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INTERMEDIATES
- the more stable intermed, easier for rxn to occur
- stabilize through induction
- degree of substitution refers to the # of substituents on an atom
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2 types of intermediates:
- electron poor: carbocations - cabonium
- radicals
electron rich: carboanions
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HYDRIDE SHIFT
move H- : to form more stable (more stable 2 o subst --> 3 o subst)
- ONLY CARBOCATIONS
-

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METHYL SHIFT
- (ONLY WKS W/ CARBOCATIONS)

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* Rules for determine R & S *
- 1. Assign priority based on atomic #
- - heavier isotope 1st
- - same atom, move one out
- - break apart multiple bonds
2. Move the 4th group into back
- 3. Go 1 → 2 → 3
- CLOCKWISE R
- COUNTER S
4. If you had to do step 2, switch R → S or S → R
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Enantiomers:
- - all chiral centers are opposites- come in pairs
- - > 1 chiral centers
- - optical activity, same magnitude
- opposite sign
- - all other properties the same
- - resolution way to separate them
- - 50/50 mixture = RACEMIC MIXTURE
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Meso compounds:
- - 1 line of symmetry & EVEN # OF CHIRAL- no optical rotation
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Diastereomers:
- - some but not all chiral centers are opposite
- - 2 or more molecules
- - separate via fractional distillation
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Substitution Rxn -- SN2
substitution nucleophilic 2 bimolecular (2nd order)
[SN --> happens all at once] SN2 --> chick (base) wants guy, girl sneaks in & kicks out other
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Principles SN2:
- 1. reactivity based on steric hindrance
- methyl > 1o > 2o > 3o
2. solvent -- aportic (have Nu - want to remain unstable)
- 3. Inversion of stereochemistry
- R → S
- S → R
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SN1
unimolar (1st order)
- [SN --> happens all @ once]
- SN1 guy is (base) waits for guy to leave & go in

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Principles SN1:
- 1. Based on stability of carbocation
- 3o > 2o > 1o > methyl
2. Solvent: protic
3. Get RACEMIC mixture
4. Shifts can occur
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Elimination rxn -- E1
- incr bond order
- E1--> waits to come off

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Principles of E1:
- 1. Reactivity based on carbocation stability
- 3o > 2o > 1o > methyl
2. Polar protic (stabilize hylide/ leaving gr from attacking again)
3. TRANS is more stable
4. Shifts can occur
5. Need β-hydrogen
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E2:
occurs w/ alkyl halide ONLY
E2 --> all @ one time
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Principles E2:
1. Reactivity based on sterics of base (more constituents is better, not always)
- 2. Large base → least substituted
- Small base → more substituted
3. No shifts
4. *Must be anti to the leaving gr
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How to favor E rxn over SN rxn...
1. HEAT: ↑ heat gives reactants enough energy to overcome the increased Ea
2. STRONG BASE: eliminations rxn use bases, not nucleophiles
3. 3o OR 2o: Both E rxn prefer 3o substitution & are minimally affected by sterics
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