Horner-Wadsworth-Emmons Reaction

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