Stereoselectivity of Metal Hydride Reduction

Sodium borohydride and lithium aluminum hydride have only moderate stereoselectivity. The anions tend to attack sterically hindered compounds from the least stericaUy hindered side. For example, reduction of bicyclo[2.2.1]heptan-2-one yields a mixture of two alcohols in which the endo compound predominates. The exo face of the carbonyl group is more open to attack by the nucleophilic hydride reagent, and as a result the endo alcohol is the major product. 

Write the structure of the product of each of the following reactions, assuming an excess of each metal hydride. 

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