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1. 2. Oxymercuration. Total of 8 racemates possible. Only 2 are formed. 2. kinetically controlled; high energy TS’s ≠. kinetically controlled; low energy TS’s ≠. 1. 1. 2. Oxymercuration – II; Add a Methyl Group. regiochemistry ; anti addition; Markovnikov.
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1 2 Oxymercuration Total of 8 racemates possible. Only 2 are formed. 2 kinetically controlled; high energy TS’s≠ kinetically controlled; low energy TS’s≠ 1
1 2 Oxymercuration – II; Add a Methyl Group regiochemistry; anti addition; Markovnikov regiochemistry; anti addition; anti - Markovnikov wrong regiochemistry boatlike TS≠ eliminated on previous slide Only product!!!
Oxymercuration - III If BD4- had been used as the reductant, a mixture of deuterio compounds would form.
diastereomers Oxymercuration - IV anti addition; Markovnikov diastereomers radical intermediate anti addition; Markovnikov
Alkyl Mercurials – Radical Oxygenation endo Endo and exomercurials give the same radical. Product distributions the same. exo RHgBr + BH4- --------> RHgH RHgH ---------> R . + .HgH R . + O2 ---------> ROO . ROO . + .HgH -------> ROOH + Hg0 ROOH + BH4- --------> ROH = R C. L. Hill and G. M. Whitesides, J. Am. Chem. Soc., 96, 1974, 870.