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250 CHAPTER 8 
 
only one alkene with the molecular formula C6H12 that 
fits this criterion: 
 
 
 
 
8.27. 
(a) Treating an alkene with catalytic osmium tetroxide 
and NMO results in the addition of OH and OH across 
the alkene. In this case, two new chiral centers are 
generated, so we expect only the pair of enantiomers that 
would result from syn addition: 
 
 
(b) Treating an alkene with osmium tetroxide followed 
by aqueous sodium bisulfite results in the addition of OH 
and OH across the alkene. In this case, only one chiral 
center is created, so we expect both possible enantiomers 
(formation of the initial cyclic osmate ester can occur on 
either face of the  bond with equal likelihood): 
 
 
(c) Treating an alkene with cold potassium permanganate 
and sodium hydroxide results in the addition of OH and 
OH across the alkene. In this case, two new chiral 
centers are generated, and we expect a syn addition, 
giving the following meso compound: 
 
 
 
(d) Treating an alkene with cold potassium 
permanganate and sodium hydroxide results in the 
addition of OH and OH across the alkene. In this case, 
the product has no chiral centers, so stereochemistry is 
not a relevant consideration. 
 
 
(e) Treating an alkene with catalytic osmium tetroxide 
and a suitable co-oxidant (tert-butyl hydroperoxide) 
results in the addition of OH and OH across the alkene. 
In this case, only one chiral center is created, so we 
expect both possible enantiomers (formation of the initial 
cyclic osmate ester can occur on either face of the  
bond with equal likelihood): 
 
 
(f) Treating an alkene with catalytic osmium tetroxide 
and NMO results in the addition of OH and OH across 
the alkene. In this case, two new chiral centers are 
generated, so we expect only the pair of enantiomers that 
would result from syn addition: 
 
 
 
8.28. 
(a) Each C=C bond is split apart and redrawn as two 
C=O bonds, giving the following products: 
 
 
 
(b) Each C=C bond is split apart and redrawn as two 
C=O bonds, giving two equivalents of the same product: 
 
 
 
(c) The C=C bond is split apart and redrawn as two C=O 
bonds, giving two equivalents of the same product: 
 
 
 
(d) The C=C bond is split apart and redrawn as two C=O 
bonds, giving the following product: 
 
 
 
(e) The C=C bond is split apart and redrawn as two C=O 
bonds, giving the following meso compound: 
 
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