Synthesis of Ginkgolide B

Structure of Ginkgolide B

C20H24O10

Principal investigatorElias J. Corey
Publication year1988
Synthesis typeTotal
Number of steps 26 (2 parts)
References
Part 1 of 2
intermediate structure + intermediate structure
(COCl)2
PhH
RT, , 85%
intermediate structure
BF3.OEt2
CH2Cl2
-20 °C, , 92%
intermediate structure
Part 2 of 2
intermediate structure
Glyoxal dimethyl acetal
PhH
RT, 18 h, 70%
intermediate structure
  1. CuCN
  2. t-BuLi
  3. TMSCl
Et2O, Et3N
-78 to -10 °C, 3 h, 93%
intermediate structure
(CH2O)3, TiCl4
MeOH
-78 °C to RT, 16 h, 65%
intermediate structure
  1. i-Pr2NLi
  2. PhNTf2
DME
-78 °C to RT, 4 h, 80%
intermediate structure + intermediate structure
CuI, n-PrNH2, Pd(PPh3)4
PhH
16 °C, 4 h, 76%
intermediate structure
  1. AcOH
  2. Cy2BH
THF
0 °C to RT, 18.5 h, 70%
intermediate structure
(COCl)2, n-Bu3N
PhH, PhMe
RT to Reflux, 3 h, 71%
intermediate structure
NaOH, Ph3COOH
Acetone, H2O
-30 °C, 2 h, 86%
intermediate structure
HS(CH2)3SH, TiCl4
CH2Cl2
0 °C to RT, 50 min, 98%
intermediate structure
AcOH, H2Cr2O7.2Pyr
CH2Cl2
0 °C, 60 min, 75%
intermediate structure
H2O, HIO4
CH2Cl2, MeOH
-30 °C to RT, 60 min, 80%
intermediate structure
Camphorsulfonic acid
MeOH
RT, , 80%
intermediate structure
Et2NLi
-25 to 0 °C, 45 min
intermediate structure
Camphorsulfonic acid
CH2Cl2
RT, 24 h, 75% (2 steps)
intermediate structure
NBS
CCl4
10 °C, 3 h
intermediate structure + intermediate structure + intermediate structure
AgNO3
MeCN
RT, 15 min, 50%
"Also isolated were two allylic nitrates, both of which were converted to the desired product. The overall yield for these transformations is shown."
intermediate structure
Pyr.TsOH, Pyr
PhCl
135 °C, 16 h, 80%
intermediate structure
Et3NBn+ i-PrO-, Ph3COOH
THF
-10 °C, 3 h, 72%
intermediate structure
EtCO2t-Bu, i-Pr2NLi
HMPA, THF
-78 to -30 °C, 12 h, 60%
See the Aldol Addition
intermediate structure
Camphorsulfonic acid
CH2Cl2
RT, 15 h, 82%
intermediate structure
2,6-Lutidine, TBSOTf
MeCN
RT, 60 min, 89%
intermediate structure
OsO4
Pyr
intermediate structure
CaCO3, I2
MeOH
RT, 12 h, 40% (2 steps)
intermediate structure
BF3.OEt2
CH2Cl2
RT, 14 h, 89%
intermediate structure