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Functionalization of N₂ via Formal 1,3-Haloboration of a Tungsten(0) ?-Dinitrogen Complex.

ABSTRACT: Boron tribromide and aryldihaloboranes were found to undergo 1,3-haloboration across one W-N?N moiety of a group 6 end-on dinitrogen complex (i.e. trans-[W(N₂ )₂ (dppe)₂ ]). The N-borylated products consist of a reduced diazenido unit sandwiched between a W^II center and a trivalent boron substituent (W-N=N-BXAr), and have all been fully characterized by NMR and IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. Both the terminal N atom and boron center in the W-N=N-BXAr unit can be further derivatized using electrophiles and nucleophiles/Lewis bases, respectively. This mild reduction and functionalization of a weakly activated N₂ ligand with boron halides is unprecedented, and hints at the possibility of generating value-added nitrogen compounds directly from molecular dinitrogen.

SUBMITTER: Rempel A

PROVIDER: S-EPMC7756771 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Functionalization of N2 via Formal 1,3-Haloboration of a Tungsten(0) σ-Dinitrogen Complex.

Rempel Anna A Mellerup Soren K SK Fantuzzi Felipe F Herzog Anselm A Deißenberger Andrea A Bertermann Rüdiger R Engels Bernd B Braunschweig Holger H

Chemistry (Weinheim an der Bergstrasse, Germany) 20201022 68

Boron tribromide and aryldihaloboranes were found to undergo 1,3-haloboration across one W-N≡N moiety of a group 6 end-on dinitrogen complex (i.e. trans-[W(N2 )2 (dppe)2 ]). The N-borylated products consist of a reduced diazenido unit sandwiched between a WII center and a trivalent boron substituent (W-N=N-BXAr), and have all been fully characterized by NMR and IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. Both the terminal ...[more]

PMID: 32957161

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