Biomedical Engineering Reference
In-Depth Information
SCHEME 9.23
Exploitation of metathesis cascades in combination with inter- and
intramolecular Diels-Alder reactions: (a) building block, DEAD, PPh
3
, THF; (b) NH
3
in MeOH
(sat.); building block; (c) NBS; CH
2
Cl
2
; (d) NaOMe, MeOH; (e) acryloyl chloride,
i-
Pr
2
NEt,
CH
2
Cl
2
; (f) 3 mol% Grubbs's first-generation catalyst, CH
2
Cl
2
,45
◦
C; Et
3
N, P(CH
2
OH)
3
; (g)
HF-pyridine, THF; (h) 3 mol% Hoveyda-Grubbs's second-generation catalyst, CH
2
Cl
2
,45
◦
C;
Et
3
N, P(CH
2
OH)
3
; (i) TFA, CH
2
Cl
2
; (j) methyl fumarate, DCC, DMAP, THF; MeCN,
w; (k)
4-phenyl-[1,2,4]-triazole-3,5-dione, CH
2
Cl
2
,TFA,CH
2
Cl
2
; (l)
p
-xylene, reflux. R
F
and R
F
denote a fluorous tag.
