Synthesis of Alkaloid GB 13

Structure of Alkaloid GB 13

C20H29NO2

Principal investigatorLewis N. Mander
Publication year2003
Synthesis typeTotal
Number of steps 31 (linear)
References
Part 1 of 1
intermediate structure + intermediate structure
Li
NH3, THF
-33 °C, 2.5 h, 75%
See the Birch Reduction
intermediate structure
H2SO4
Acetone, H2O
0 °C, 2 h, 80%
intermediate structure
AcOH
H2O
Reflux, 16 h, 89%
intermediate structure
DMAP, i-Pr2NEt, MeOCH2Cl
CH2Cl2
0 °C to RT, 16 h, 97%
intermediate structure
NaH, HCO2Me
THF
0 °C, 17 h
intermediate structure
Et3N, NsN3
MeCN
0 °C to RT, 2 h
intermediate structure
TMS2NH
THF
RT, 6 h, 68% (3 steps)
intermediate structure
Et3N, Cl3CCOCl
CH2Cl2
0 °C, 5 min, 98%
intermediate structure intermediate structure
  1. KOt-Bu
  2. i-Pr2NLi
  3. (PhSe)2
THF
0 °C, 100 min
intermediate structure intermediate structure
H2O2
EtOAc, H2O, THF
0 °C, 2 h, 74% (2 steps)
intermediate structure + intermediate structure
110 °C, 3 d, 87%
intermediate structure
n-Bu4N+ F-
THF
0 °C, 60 min, 74%
intermediate structure
LiAlH4
Et2O, THF
-78 °C, 5 min, 94%
intermediate structure
DMAP, i-Pr2NEt, MeOCH2Cl
CH2Cl2
0 °C to RT, 16 h, 96%
intermediate structure
Li
EtOH, NH3, THF
-78 to -33 °C
See the Birch Reduction
intermediate structure
HCl
H2O, MeOH, THF
RT, 45 min, 55% (2 steps)
intermediate structure
LiAlH4
Et2O
0 °C, 30 min
intermediate structure
mCPBA
CH2Cl2, Buffer (pH = 6.5)
RT, 2 h
intermediate structure
Dess-Martin Periodinane, NaHCO3
CH2Cl2
RT, 2.5 h, 77% (3 steps)
intermediate structure
Pyr, NsNHNH2
THF
-78 °C to RT, 9 h, 76%
intermediate structure
NH2OH.HCl
Pyr
95 °C, 4 h
intermediate structure
NaBH4, ZrCl4
THF
RT, 16 h
intermediate structure
Zn
AcOH, Et2O
RT, 4 h
intermediate structure
Pyr, (CF3CO)2O
CH2Cl2
RT, 3 h, 32% (4 steps)
intermediate structure
HCl
Acetone, H2O
50 °C, 16 h
intermediate structure
Dess-Martin Periodinane
CH2Cl2
RT, 4 h, 80% (2 steps)
intermediate structure
DMAP, i-Pr2NEt, MeOCH2Cl
CH2Cl2
0 °C to RT, 16 h, 71%
intermediate structure
  1. i-Pr2NLi
  2. TMSCl
THF
-78 °C, 35 min
intermediate structure
Pd(OAc)2
DMSO, MeCN
RT, 16 h, 82% (2 steps)
intermediate structure
K2CO3
H2O, MeOH
55 °C, 16 h
intermediate structure
HCl
Acetone, H2O
55 °C, 20 h, 37% (2 steps)
intermediate structure