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Abstract We report reversible B←N coordinate bond formation and cleavage in the organic solid state. The dynamic behavior was probed using the [2 + 2]-photodimerization of 4-(1-naphthylvinyl)pyridine (4-nvp) as a chemical reporter under concurrent mechanochemical vortex grinding and ultraviolet light-emitting diode (UV-LED) irradiation. Phenylboronic acid catechol ester (pbe) templates the regio- and stereoselective formation of 1,3-bis(4-pyridyl)-2,4-bis(1-naphthyl)cyclobutane (pncb), and the reaction proceeds efficiently even when pbe is used in substoichiometric amounts (50%, 30% and 5% mol). The catalytic turnover demonstrates that B←N bonds can break and reform dynamically under mechanical stress in the organic solid state, establishing B←N coordination as a design element for responsive molecular materials.
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Tandem Diboration–Protoboration of Terminal Alkynes: A Practical Route to α-Substituted Alkenyl Boronates
Abstract A practical method is introduced for the catalytic conversion of terminal alkynes into α-substituted vinyl boronic esters. The process employs catalytic amounts of nanoparticle-supported gold catalysts and catalytic amounts of copper to effect the overall transformation.
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- Award ID(s):
- 2117246
- PAR ID:
- 10539063
- Publisher / Repository:
- SynLett
- Date Published:
- Journal Name:
- Synlett
- ISSN:
- 0936-5214
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1055/s-0043-1774906
