A Boron-Boron Double Transborylation Strategy for the Synthesis of gem-Diborylalkanes
Keyword(s):
9-Borabicyclo[3.3.1]nonane (H-<i>B</i>-9-BBN) has been used as a catalyst for the sequential double hydroboration of alkynes with pinacolborane (HBpin) to give alkyl gem-di-pinacol boronic esters. This strategy, which is effective for a wide range of terminal alkynes, is predicated upon a key C(<i>sp</i><sup>3</sup>)-B / B-H transborylation reaction. Transition-state thermodynamic parameters and 10-boron-isotopic labelling experiments are indicative of an <i>σ</i>-bond metathesis exchange pathway.
2020 ◽
Vol 18
(31)
◽
pp. 6072-6076
◽
Keyword(s):
2006 ◽
Vol 47
(17)
◽
pp. 2961-2964
◽
2004 ◽
Vol 50
(10)
◽
pp. 877-881
◽
Keyword(s):