Week 4 Reactions Flashcards
Halogenation
Cl2, AlCl3 OR Br2, FeBr3
————–> —————>
Ortho and para positions
Nitrogenation
HNO3, H2SO4
———————>
Meta position
Friedels-Crafts Alkylation
t-Butyl-Cl, AlCl3
———————->
t-Butyl, iPr, intramolecularly
NEW C-C BOND
Friedels-Crafts Acylation
Acid chloride, AlCl3
—————————->
R: only alkene FGs
NEW C-C BOND
SNAR
Nu:
—->
EWG ortho/para to LG
EWG often NO2 or ketone
Use OH-/OR- or SH-/SR- for synthesis
Ketone/aldehyde to 3* alcohol
- RMgBr, Et2O
- ——————–> - H+ wkup
Cannot use on acidic protons: deprotonate and reprotonate
Grignard Addition
NEW C-C BOND
Ketone/Aldehyde Reduction
Ketone/aldehyde to 2* alcohol
NaBH4, EtOH
——————->
Reversible Carbonyl Addition: Ketone/aldehyde to acetal
ROH, H+ cat.
——————>
Protonate, ROH attack, H+ transfer, LPP, ROH attack, sol
Reversible Carbonyl Addition: Ketone/aldehyde to hemiacetal
RO-, ROH
————–>
RO- attack, H-OR protonate
Reversible Carbonyl Addition: Ketone/aldehyde to cyanohydrin
NaCN, ROH
—————–>
CN- attack, H-OR protonate
Doesn’t work on esters or carb. acids (+ derivs).
Reversible Carbonyl Addition: Ketone/aldehyde to imine
RNH2, pH=5
——————>
Protonate, RNH2 attack, H+ transfer, LPP, sol
Reversible Carbonyl Addition: Ketone/aldehyde to enamine
R2NH, pH=5
——————>
Protonate, R2NH attack, H+ transfer, LPP, H+ mvmt to form double bond
Acetal Hydrolysis
H3O+
——–>
Protonate, LPP, H2O attack, H+ transfer, LPP, sol
Imine Hydrolysis
H3O+
——–>
Protonate, H2O attack, H+ transfer, LPP, sol
Enamine Hydrolysis
H3O+
——–>
LPP and protonate, H2O attack, H+ transfer, LPP, sol
Imine or enamine to 2* amine
H2, Pd/C
————->
Removing double bond and adding H
Imine Reduction
Ketone/aldehyde to 2/3 amine
+ RNH2/R2NH NaBH3CN, pH=5
————————->
Protonate, RNH2/R2NH attack, H+ transfer, LPP, BH3CN attack (pushing double bond up/adding H)
Reductive Amination
Wittig: Alkyl halide to ylide
- PPh3
- ———-> - n-BuLi
SN2, deprotonate
Wittig: Ylide to alkene
O
||
R R’
——–>
PPh3 LP attack, O LP to PPh3+, CP -> CO
Favors cis alkenes
NEW C=C BOND
One-Step Carbonyl Reduction: Clemmensen
Aldehyde/ketone to bottom part of aldehyde/ketone (alkane)
Zn, HCl
———–>
Just “erase” C=O
Grignard to carboxylic acid
- CO2
- ——–> - H+ wkup
R-MgBr attack C in O=C=O, H+ wkup to protonate O:-
Transesterification
Ester with R to Ester with R”
ROH, H+
————>
Protonate, ROH attack, H+ transfer, LPP, sol
Transesterification: Going backwards
RO-, ROH
————–>
RO- attack, LPP (old) OR’ off
Carboxylic Acid Derivative Hydrolysis: Acid chloride to carboxylic acid
H2O
——->
H2O attack, LPP, sol
Carboxylic Acid Derivative Hydrolysis: Amide to carboxylic acid
H2O, H+, heat
——————–>
Protonate, H2O attack, H+ transfer, LPP, sol
Carboxylic Acid Derivative Hydrolysis: Ester to carboxylic acid
- OH-, H2O
- —————> - H+ wkup
OH- attack, LPP, deprotonate with H2O (or ROH), reprotonate with H+ wkup
Carboxylic Acid Derivative Hydrolysis: Nitrile to carboxylic acid
H2O (2 equiv.), H+, heat
———————————->
Protonate, H2O attack, H+ transfer, LPP, sol
Forming acid chloride
Carboxylic acid to acid chloride
SOCl2
———>
Attack SOCl2, Cl- attack, LPP, sol
Reacting Acid Chlorides: Acid chloride to ester
ROH
——->
Cl replaced with OR
Acid chloride to amide
RNH2
——–>
pyr
RNH2 attack, LPP, pyr (acting as sol)
For 1: NH3
For 2: RNH2
For 3*: R2NH
Reduction of CADs: Ester to 1* alcohol
- LAH, Et2O
- —————-> - H+ wkup
LAH attack, LPP, LAH, H+ wkup
LAH double addition (ester with LAH)
Reduction of CADs: Carboxylic acid to 1* alcohol
- LAH, Et2O
- —————-> - H+ wkup
LAH attack, H+ wkup
Reduction of CADs: Amide to amine
- LAH, Et2O
- —————-> - H+ wkup
Just “erase” C=O
Reduction of CADs: Nitrile to 1* amine
- LAH, Et2O
- —————-> - H+ wkup
Acid chloride to 3* alcohol
- RMgBr
- ————> - H+ wkup
RMgBr attack, LPP, RMgBr attack, H+ wkup
Double addition of Grignards
2 NEW C-C BONDS
Ester to 3* alcohol
- RMgBr
- ————> - H+ wkup
RMgBr attack, LPP, RMgBr attack, H+ wkup
Double addition of Grignards
2 NEW C-C BONDS
Partial Reductions: Acid chloride to ketone
RZnBr
———>
RZnBr, LPP
“Zignard”
NEW C-C BOND
Partial Reductions: Ester to aldehyde
- DIBAL-H, -78* C
- ————————> - H+ wkup
Attack DIBAL-H, OR LP to Al, H+ wkup
Baeyer-Villiger Oxidation
Ketone to ester
mCPBA
———–>
Attack H on mCPBA, O:- on mCPBA attacks C=O, OH LP forms double bond and more substituted C-R attacks O on mCPBA, O:- attacks H on ester
BREAKS C-C AND ADDS O
Can expand rings