Cyclooctane boron complex

C4H,o, 1,3,5-Cyclooctatriene, ruthenium complex, 22 178 CgHl2, 1,5-Cyclooctadiene, iridium complexes, 23 127 rhodium complex, 23 127, 129 ruthenium complex, 22 178 C8H]4, Cyclooctene, iridium complex, 21 102 CsH16, Cyclooctane, boron complex, 22 199... 

There are a wide variety of hydroborating reagents, including BH3 complexes, pinacolborane, thexyl borane, and catechol borane. The following employs 9-borabicyclo[3.3.1]nonane (9-BBN), which places the boron on the less sterically hindered carbon with high regioselectivity however, completely removing the cyclooctane by-products can be problematic. The alkylborane can be isolated, but is typically used directly in the next reaction, in this case oxidation to the primary alcohol. 

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