FINAL - Reactions

Alkene: HBr/HCl

Add halide on more sub side.

1. Protonate alkene (C+ on more sub side)

2. C+ rearrange?

3. Add halide

4. Chiral center?

Carbocation rearrangement

Movement of C+ to more stable position (nextdoor neighbor)

1. Hydride Shift - movement of H

2. Methyl Shift - movement of CH3

3. Ring Expansion - expansion of 3, 4, or 5 membered ring

Alkene: H2O / H2SO4 (or H3O)(if CH3OH: add OCH3)

Add OH on more sub side (rearrangement)

1. Protonate alkene (C+ on more sub side)

2. C+ rearrange?

3. Add H2O

4. Deprotonate

5. Chiral center?

Alkene: Br2 / CH2Cl2

Add halide on both sides: anti (wedge/dash)

1. 3 arrows: alkene attacks halide, bond breaks, halide attacks back

2. Bridge is made

3. Leftover halide attacks either carbon of bridge

4. Bridge broken: halide now on both carbons, anti

Alkene: Br2 / H2O

Add halide and OH - anti (wedge/dash), OH on more sub side

1. 3 arrows: alkene attacks halide, bond breaks, halide attacks back

2. Bridge is made

3. H2O attacks more sub carbon of bridge

4. Bridge broken: halide now on one carbon, anti

5. Deprotonate H2O → OH

Alkene: 1. Hg(OAc)2, H2O / 2. NaBH4

Add OH to more sub side

Alkene: 1. BH3, THF / 2. H2O2, NaOH

Add OH to less sub side (syn-addition: OH & H)

Alkene: OsO4 / H2O2, H2O

Add OH on both sides (syn: same side)

Alkene: 1. O3 / 2. (CH3)2S

1. Split double bond

2. Redraw both sides

3. Add “O”s

(2 products)

Alkene: H2 / Pt/Pd/Ni

Add syn “H”s (get rid of pi bond)

Alkyne: Br2 (1 eq.) / CH2Cl2

Add halide on both sides (left with double bond)

Alkyne: Br2 (2 eq.) / CH2Cl2

Add 2 halides on both sides (left with single bond)

Alkyne: HBr (1 eq.)

Add halide on more sub side (left with double bond)

Alkyne: HBr (2 eq.)

Add 2 halides on more sub side (left with single bond)

Alkyne: HgSO4 / H2SO4, H2O

Add C=O (ketone) to the more sub side.

Alkyne: 1. (Sia)2BH, THF, H2O / 2. H2O2, NaOH

Add C=O (aldehyde/ketone) to the less sub side

Alkyne: H2 / Pt/Pd/Ni

Triple bond reduced to (3→1) single bond

Alkyne: H2 / Lindlar’s Catalyst

Triple bond reduced to cis (Z) double bond.

Alkyne: Na / NH3 (l)

Triple bond reduced to trans (E) double bond.

Alkyne: 1. NaNH3 (3 eq.) / NH3 / 2. H2O

Halides are removed one at a time (creating pi bonds)

Alkyne: 1. LDA/THF / 2. EtBr

Prepare alkyne and add extra carbons.

Alkyne: Na+-(Carbon Triple Bond)

Replaces halide with alkyne

Radical Reactions: Br2/ light

Add Br to most sub. position

Radical Reactions: Cl2 / light

Add Cl individually to every possible radical position (multiple products)

1. Initiation: no radicals → radicals

2. Propagation: radicals → radicals

3. Termination: radicals → no radicals

Radical Reactions: NBS / heat

1. Add radical next door to alkene

2. Resonate

3. Add the Br

Radical Reactions: HBr / ROOR + heat

Add Br on less sub. side

SN2 - What It Likes

• strong nucleophile

• 3^. leaving group

• aprotic aolvent

SN2 - Mechanism

1. Nucleophile attacks base of leaving group

2. Leaving group leaves

3. Nucleophile is added (flip stereochem)

SN1 - What It Likes

• weak nucleophile

• 3^. leaving group

• protic solvent

SN1 - Mechanism

1. Leaving group leaves

2. C+ forms

3. Shift or resonate?

4. Nucleophile adds in

5. Deprotonate nucleophile

E1 - What It Likes

• weak nucleophile

• 3^. leaving group

• protic solvent

E1 - Mechanism

1. Leaving group leaves

2. C+ forms

3. Shift or resonate?

4. Nucleophile grabs H

5. Bond moves to make C=C

E2 - What It Likes

• Strong nucleophile

• 3^. leaving group

• protic solvent

E2 - Mechanism

1. Nucleophile grabs H

2. Bond moves to make C=C

3. Leaving group leaves

ANTI & COPLANAR

Alcohols: Na^., Li^., K^. / NaH or NaNH₂

Preparation to make -O—R (nucleophile ready to attack)

Alcohols: HBr/HCl/HI

• Primary (1) alcohol: SN2 replace OH with Br (OH bad leaving group)

• Secondary (2) alcohol: SN2 and SN1/E1 possible (won’t see besides obvious substitution)

• Tertiary (3) alcohol: SN1 replace OH with Br

• Primary (1) with B-BRANCHING: SN1 with rearrangement

Alcohols: PBr3

Replaces OH with Br (stereochem flips)

Alcohols: SOCl2 / Pyridine

Replaces OH with Cl (stereochem flips)

Alcohols: TsCl / pyridine

Replaces OH with OTs (stereochem stays same)

Alcohols: H2SO4 (cat) / heat

Remove OH for C=C

1. Protonate OH

2. OH2 leaves

3. C+ forms (shift?)

4. H2O grabs H

5. Bond moves to form C=C

Alcohols: PINACOL REARRANGEMENT - H2SO4 (cat) / heat

1. Protonate

2. Leave

3. Shift

4. Resonate

5. Deprotonate

PLSRD

Alcohols: PCC

• Primary (1) alcohol → aldehyde

• Secondary (2) alcohol → ketone

• Tertiary (3) alcohol → NOTHING

Alcohols: H2CrO4 or Jone’s Reagent, CrO3 / H2SO4, K2Cr2O7 / H2SO4

• Primary (1) alcohol → carboxylic acid

• Secondary (2) alcohol → ketone

• Tertiary (3) alcohol → NOTHING

Alcohols: HIO4

Chop between cis OH/s → aldehyde or ketone

Ethers: Na^.,Li^.,K^. / NaH or NaNH₂ (next reaction: CH₃Br →) - WILLIAMSON-ETHER SYNTHESIS

Prepare OH (O-), creating nuc to attack new carbons

Ethers: 1. Hg(OAc)₂, CH₃OH / 2. NaBH₄

Add CH₃O to more sub side

Ethers: HBr/I

Cleave ether to carbons + LG (have to be able to do SN2 reaction)

Epoxides: Br2 / H2O (next reaction: NaOH / H2O)

Add anti Br and OH, deprotonate OH (makes nuc), attacks, forms epoxide

Epoxides: mCPBA

Add epoxide ( -O- ) on a double bond

Epoxides: H2O / H2SO4 (cat.) - WEAK NUC

Acid-catalyzed ring opening

• protonate

• H2O attacks MORE sub side (follow bridge stereochem)

REMEMBER: PAD

Epoxides: NaOEt / EtOH - STRONG NUC

Nucleophilic ring opening

• protonate

• nuc attacks LESS sub side (follow bridge stereochem)

REMEMBER: AP