Monobenzofused 1,4-Azaborines: Synthesis, Characterization, and Discovery of a Unique Coordination Mode†
Dr. Senmiao Xu
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Fredrik Haeffner
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Bo Li
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Lev N. Zakharov
Center for Advanced Materials Characterization in Oregon, University of Oregon, Eugene, OR 97403-1253 (USA)
Search for more papers by this authorCorresponding Author
Prof. Dr. Shih-Yuan Liu
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)Search for more papers by this authorDr. Senmiao Xu
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Fredrik Haeffner
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Bo Li
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Search for more papers by this authorDr. Lev N. Zakharov
Center for Advanced Materials Characterization in Oregon, University of Oregon, Eugene, OR 97403-1253 (USA)
Search for more papers by this authorCorresponding Author
Prof. Dr. Shih-Yuan Liu
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)
Department of Chemistry, Boston College, Chestnut Hill, MA 02467 (USA)Search for more papers by this authorCorrespondence concerning X-ray crystallography should be directed to Lev N. Zakharov ([email protected]) and Bo Li (complex 8 h, 11; [email protected]). Correspondence concerning electronic structure calculations should be directed to Fredrik Haeffner ([email protected]). Portions of this work were carried out at the University of Oregon. Support for this work has been provided by the National Science Foundation (CHE-1212346) and by Universal Display Corporation.
Graphical Abstract
Breaking N-BC News: The first general synthesis of boron-substituted monobenzofused 1,4-azaborines has been developed. As part of the synthetic investigations, a unique κ2-N-η2-BC coordination mode was discovered and investigated.
Abstract
We report the first general synthesis of boron-substituted monobenzofused 1,4-azaborines using ring-closing metathesis of an enamine-containing diene as a key synthetic strategy. As part of our investigations, we discovered that the B-C3 moiety in a 1,4-azaborine can serve uniquely as a η2-L-type ligand. This functionality is exemplified by two κ2-N-η2-BC Pt complexes of a boron-pyridyl-substituted monobenzofused-1,4-azaborine. Single-crystal X-ray diffraction analysis of the Pt complexes shows a strong structural contribution from the iminium resonance form of the monobenzofused-1,4-azaborine ligand. We also demonstrate that a palladium(0) complex supported by a 1,4-azaborine-based phosphine ligand can catalyze hydroboration of 1-buten-3-yne with unique selectivity. In view of the importance of arene–metal π-interactions in catalytic applications, this work should open new opportunities for ligand design involving the 1,4-azaborine motif as an arene substitute.
Supporting Information
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