Synthesis of Yohimbine

Structure of Yohimbine

C21H26N2O3

Principal investigatorEugene E. van Tamelen
Publication year1958
Synthesis typeFormal
Number of steps 20 (linear)
References
Part 1 of 1
intermediate structure + intermediate structure
PhH
RT, 2-3 weeks, 93%
intermediate structure
Zn
AcOH
30-50 °C, 40 min, 93%
intermediate structure
KOt-Bu, ClCH2CO2Et
PhH, t-BuOH
RT, ON, 81%
intermediate structure
NaOH
H2O
RT to 100 °C, 45 min, 87%
intermediate structure
Cu
Diethylene glycol
155-160 °C, 2 h, 76%
intermediate structure
AgNO3, KOH
EtOH, H2O
RT, 12 h, 38%
intermediate structure
(COCl)2, Pyr
Et2O
RT, 8 h
intermediate structure + intermediate structure
Pyr
CHCl3
5 °C, 10 h, 75% (2 steps)
intermediate structure
OsO4, Pyr
Et2O, THF
-78 °C, 2.5 h, 56%
"Single, unidentified cis-isomer. Also isolated was the other cis-diastereoisomer (11 % yield)."
intermediate structure
H2, PtO2
EtOH
RT, 60 min, 85%
intermediate structure
H3PO4, NaIO4
Acetone, H2O
60-70 °C, 20 min, 60%
intermediate structure
TsOH
MeOH
RT, 3 d, 77%
intermediate structure
LiAlH4
THF
Reflux, 4 h, 76%
intermediate structure
HCl
H2O
100 °C, 3 h, 82%
intermediate structure
Ac2O
Pyr
RT, ON
intermediate structure
285-295 °C, 5 min, 71% (2 steps)
intermediate structure
OsO4, Pyr
THF
-78 °C, 7 h, 37%
intermediate structure
NaIO4
H2O, MeOH
0 °C, 2 h, 81%
intermediate structure
CrO3, H2SO4
Acetone, H2O, MeOH
0 °C, 30 min, 16%
See the Jones Oxidation
intermediate structure
Remaining...
65% (2 steps)
"See : Acta Chim. Scand. 1956, 10, 1414."
intermediate structure