Stereoselectivity in some hydroboration-oxidations of alkenes with di-3-pinanylborane

Steric features in the diastereomeric transition states are no doubt the governing factor in determining the extent and direction of selectivity in asymmetric hydro-borations. A number of varying representations of the transition states have been offered, however, and it is not clear exactly which interactions are dominant in controlling stereochemistry.  

Moderate enantiomeric enrichment has been obtained in Diels-Alder reactions of optically active esters of acrylic acids  

Hydrolysis of the ester gives optically active acid, demonstrating that an excess of one 

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Table 10.1. Stereoselectivity in Some Hydroboration-Oxidations of Alkenes with Di-3-pinanylborane ...

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