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Reactivity of gold and copper acetylide with a secondary borane
Ragene A Thornton1, Kirk French1, Kevin Shuford1
1Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, TX 76798, USA. caleb_d_martin@baylor.edu.
Abstract:
Gold(I) triphenylphosphine phenylacetylide reacts with bis(1-methyl-ortho-carboranyl)borane to give a hydroboration product that is best described as an η2-1-borataallene gold complex. Contrarily, the analogous reaction with the copper acetylide undergoes transmetalation to furnish an alkynylborate with the CuPPh3+ moiety bound to the alkyne and a hydride bridging boron to copper. The compounds were analyzed by single crystal X-ray diffraction and DFT computations that rationalize the unusual bonding arrangements.
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