Hydroboration ketone substrates

Alpine-Borane (Midland) Alpine-Borane is a trademark of Aldrich Chemical Company for B-3-pinanyl-9-borabicyclo[3.3.1]nonane. It is prepared by hydroboration of a-pinene with 9-borabicyclo[3.3.1]nonane (9-BBN). Synthesis of (1 )-Alpine-Borane is prepared from (17 )-(+)-a-pinene, and since (+)- and (-)-a-pinenes are commercially available, both enantiomers of the reagent can easily be prepared. The reagent is only suitable for very reactive substrates, such as labeled aldehydes and acetylenic ketones (Scheme 2.136) [64],... 

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