Halonium ion-assisted deiodination of styrene-based vicinal iodohydrins followed by rearrangement through phenyl migration.
Acid activation of bromate/bromide couple at 0-10 degrees C was found to trigger the deiodination of styrene-based vicinal iodohydrins. Violet coloration of the organic layer was ascribed to formation of IBr. Deiodination was followed by phenyl migration and deprotonation leading to formation of phenyl acetone and 2-phenylpropanal in good yields from 1-iodo-2-phenylpropan-2-ol and 2-iodo-1-phenylpropan-1-ol, respectively. Phenyl acetaldehyde--which was obtained in 92% GC yield from styrene iodohydrin--was also presumably formed in analogous manner. NBS and HOCl too were effective for transformation of styrene iodohydrin into phenyl acetaldehyde.
Agrawal
Manoj K
MK
Central Salt and Marine Chemicals Research Institute (Council of Scientific & Industrial Research), G. B. Marg, Bhavnagar 364 002, Gujarat, India.
Ghosh
Pushpito K
PK