Wednesday, December 12, 2007

ortho-directed reaction of phenol

1. lewis acid-acid chloride/halides
usually no selectivity, both ortho and para product can be formed.

2 dibalH-ester
ester reduced by dibalH, then Al chelate with the phenol to give only ortho product(diol).

3. phenylboronic acid/aldehyde
boron atom formed bonds with the aldehyde and the phenol. same as dibalH, but gives boron complex, after H2O2 oxidation, gives diol.

4. alcl3/BCl3/cynide
gives phenol ketone after hydrolysis.

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