Synthesis of Zaragozic Acid C

Structure of Zaragozic Acid C

C40H50O14

Principal investigatorDavid A. Evans
Publication year1994
Synthesis typeTotal
Number of steps 29 (3 parts)
References
Part 1 of 3
intermediate structure + intermediate structure
n-Bu2BOTf, Et3N
CH2Cl2
-78 to -40 °C, 2.5 h, 96%
intermediate structure
TBSOTf, 2,6-Lutidine
CH2Cl2
0 °C, 60 min
intermediate structure
LiBH4
THF, MeOH
0 °C, 3.5 h
intermediate structure
(COCl)2, DMSO, Et3N
CH2Cl2
-78 to 0 °C, 90 min, 92% (3 steps)
See the Swern Oxidation
intermediate structure
Part 2 of 3
intermediate structure
AllylMgBr
THF
0 °C, , 93%
intermediate structure
Et2BOMe, NaBH4
MeOH, AcOH
85%
intermediate structure
2,2-Dimethoxypropane, Pyr.TsOH
PhH
98%
intermediate structure
Li
NH3, THF
-60 °C, , 100%
See the Birch Reduction
intermediate structure
""This iodide was readily prepared from intermediates previously reported by us""
intermediate structure
Part 3 of 3
intermediate structure
Cyclopentanone dimethyl acetal, TsOH
PhH
65 °C, 12 h, 85%
intermediate structure
  1. TMS2NLi
  2. TMSCl
THF
-78 to 0 °C, 60 min, 97%
intermediate structure + intermediate structure
i-PrOTiCl3
CH2Cl2
-78 to -40 °C, 4.5 h, 76%
intermediate structure
Dess-Martin Periodinane, Pyr
CH2Cl2
RT, 8 h, 94%
intermediate structure
VinylMgBr
CH2Cl2, THF
-78 °C, 10 h, 76%
intermediate structure
OsO4, NMO
t-BuOH, THF, H2O
40 h
intermediate structure
Pb(OAc)4
PhH
20 min
intermediate structure
n-Pr4N+ RuO4-, NMO
CH2Cl2
RT, 5 h, 84% (3 steps)
intermediate structure
  1. O3
  2. Pyr
  3. Me2S
CH2Cl2
-78 °C to RT, 4 h
intermediate structure
NaClO2, NaH2PO4, 2-Methyl-2-butene
t-BuOH
3.5 h
intermediate structure
N,N'-diisopropyl-O-tert-butylisourea
CH2Cl2
24 h, 91% (3 steps)
intermediate structure + intermediate structure
t-BuLi
Hexane(s), Et2O
-78 °C, 20 min, 73%
intermediate structure
DDQ
CH2Cl2
60 min
intermediate structure
Ac2O, DMAP
PhH, Pyr
90% (2 steps)
intermediate structure
H2O
CF3CO2H, CH2Cl2
intermediate structure
N,N'-diisopropyl-O-tert-butylisourea
CH2Cl2
24 h, 52% (2 steps)
intermediate structure
H2, Pd/C
MeOH, AcOH
20 h, 96%
intermediate structure + intermediate structure
DCC, DMAP
CH2Cl2
36 h, 82%
intermediate structure
n-Bu4N+ F-
THF
0 °C, 15 min, 99%
intermediate structure
CF3CO2H
CH2Cl2
24 h, 99%
intermediate structure