Horner-Wadsworth-Emmons Reaction
Mechanism of the Horner-Wadsworth-Emmons Reaction
Sample reactions
n-BuLi
THF
-78 to 0 °C, 2 h, 84%
NaH
THF
RT, , 82%
NaH
DME
RT, 60 min, 70% (2 steps)
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C to RT, 12.5 h, 49% (2 steps)
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C to RT, 12.5 h, 41% (2 steps)
NaH
DME
0 °C to RT, 5 h, 80%
TMS2NLi
THF
-78 °C, 12 h, 85%
n-BuLi
Et2O, THF
-98 °C to RT, 3 h, 85%
NaH
THF
0 °C to RT, 60 min, 96%
n-BuLi
DME
0 °C to RT, 40 min, 100%
NaH
THF
-78 °C to RT, ON, 71%
i-Pr2NLi
THF
-78 °C to RT, ON, 77% (2 steps)
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C to RT, 4 h, 84%
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C to RT, 4 h, 80% (2 steps)
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C to RT, 4 h, 60% (2 steps)
KOt-Bu
THF
-78 °C to RT, 13.5 h, 98%
KOt-Bu
THF
-78 °C to RT, 13.5 h, 98%
i-Pr2NLi, HMPA
THF
-78 to 0 °C, 60 min
i-Pr2NLi, Ph2P(O)CH2OMe
THF
0 °C to RT, 25 h, 72%
TMS2NK, (EtO)2P(O)CH2CN
THF
RT, 42 h, 43%
"Also isolated was the Z-isomer (29 % yield) which could be photoisomerized to the desired E-isomer."
TMS2NK, (EtO)2P(O)CH2CO2Me
THF
0 °C to RT, 8.5 h, 64%
TMS2NK, (EtO)2P(O)CH2CO2Me
THF
RT, 2.5 h, 39%
"Also isolated was the Z-isomer (42 % yield) which could be photoisomerized to the desired product."
TMS2NK, 18-Crown-6, (EtO)2P(O)CH2SeMe
THF
-78 °C to RT, 90 min, 81%
NaH
THF
0 °C, , 87%
Ba(OH)2
H2O, THF
87% (2 steps)
i-Pr2NEt, LiCl
DMF
RT, 44 h, 34%
"The yield was 67 % brsm. Also isolated was the Z-isomer (13 % yield)."
i-Pr2NEt, LiCl
MeCN
RT, 60 min, 81%
NaH, (EtO)2P(O)CH2CO2Et
DME
RT, 3 h, 76%
NaH, (EtO)2P(O)CH2CO2Et
THF
0 °C, , 70%
NaH, (MeO)2P(O)CH2CO2Me
THF
0 to 50 °C, 4.5 h, 83%
1,1,3,3-Tetramethylguanidine
THF
0 °C to RT, 6 h, 66%
"Also isolated was the E-isomer (10 % yield)."
KOt-Bu
THF
0 °C, 18 h, 72%
K2CO3, 18-Crown-6
PhMe
RT, 2.5 h, 100%
LDA
THF
-78 °C to RT, , 78%
Ba(OH)2
H2O, THF
RT, 8 h, 93% (2 steps)
i-Pr2NEt, LiCl
MeCN
RT, 12 h, 55%
"Also produced were 2 other diastereomers (20% yield)"