Abstract
A new, efficient and highly selective deprotective method of
both benzyl and benzylidene groups for protection of monohydroxyl
and dihydroxyl, respectively, has been developed by using the system
K-t -BuNH2 -t -BuOH-18-crown-6. This method
is valuable since it can not only selectively protect the TBDMS
and THP groups and the ethylene ketal from cleavage, but also keep
the separate or conjugated C=C bonds from reduction. A
possible electron transfer reaction process was also suggested.
Key words
selective - benzyl - benzylidene - potassium - electron transfer
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