Double FLP-Alkyne Exchange Reactions: A Facile Route to Te/B Heterocycles

• DOI: 10.1021/jacs.5b09526
• Publication Date: 2015-10-08T19:25:45Z
• Authors: Fu An Tsao; Levy Cao; Stefan Grimme; Douglas W. Stephan
• Keywords: 01 natural sciences; 0104 chemical sciences

1-Bora-4-tellurocyclohexa-2,5-diene undergoes sequential [4 + 2] cycloadditions/alkyne-elimination reactions to incorporate 2 equiv of terminal alkyne with the loss of diarylalkyne, affording access to a series of 11 new tellurium-boron heterocycles. These alkyne exchange reactions proceed regioselectively and can tolerate a variety of functional groups, thus providing the potential for further derivatization. The mechanism of the exchange reaction is confirmed by a DFT study to involve the interaction of the Te and B with the alkyne in a frustrated Lewis pair fashion in the transition states.