A Surprise in the Synthesis of Guanacastepene A
5
OCD O 2 CD 3
O
EtO
O
O
NaOCD 2 CD 3
CD 3 CD 2 OH
O
CD 3 CD 2 O
H OH
D
D
D
O
[O]
O
CD 3 CD 2 O
D
D
D
D
O
O
CD 3 CD 2 O
O
D
D
D D
D
D O
acidic
acidic
2
3-d 9
acidic
transesterification
10
5-d 8
Scheme 1.6
O
EtO
O
NaOEt
O
EtO
O
O
OEt
O
EtOH
EtOH
O
O
OEt NaOEt
O
O
O
EtO
O
O
11
-EtOAc
12
acidic
acidic
2
4
O
O
Scheme 1.7