Chemistry Reference
In-Depth Information
O
O
75 %
O
DMC
OH
O
O
NaH
reflux
30 min
CO
2
Me
H
O
O
O
969
970
971
An e
cient approach to highly functionalized hydrochrysenes 971 relies on an in-
tramolecular Friedel-Crafts alkylation. The corresponding intermediate is a carbo-
nate 970, which is prepared in 75% yield from the alcohol 969 using DMC as the
carbonylating reagent [680].
DMC
O
0.25 eq
OH
O
O
CsCO
3
972
973
64 %
120°C, 4 h
O
O
O
OH
DMC
87 %
0.25 eq
CsCO
3
120°C, 4 h
O
H
974
975
DMC has proved to be a reagent capable of accomplishing two different reactions at
the same time. The aliphatic alcohol groups in geraniol 972 and estradiol 974 are
carbonylated affording methyl carbonates 973 (64% yield) and 975 (87% yield), re-
spectively; in the case of estradiol 974 the phenolic hydroxy function is simulta-
neously methylated to give the ether moiety in 975 [681].
OH
DMC
O
+
2 MeOH
2
Bu
2
SnO
O
O
87 %
DPhC
