Dataset Information

N-Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D-?-A Compounds.

ABSTRACT: N-heterocyclic olefins (NHOs), relatives of N-heterocyclic carbenes (NHCs), exhibit high nucleophilicity and soft Lewis basic character. To investigate their ?-electron donating ability, NHOs were attached to triarylborane ?-acceptors (A) giving donor (D)-?-A compounds?1-3. In addition, an enamine ?-donor analogue (4) was synthesized for comparison. UV-visible absorption studies show a larger red shift for the NHO-containing boranes than for the enamine analogue, a relative of cyclic (alkyl)(amino) carbenes (CAACs). Solvent-dependent emission studies indicate that 1-4 have moderate intramolecular charge-transfer (ICT) behavior. Electrochemical investigations reveal that the NHO-containing boranes have extremely low reversible oxidation potentials (e.g., for 3, Eox1/2 =-0.40?V vs. ferrocene/ferrocenium, Fc/Fc+ , in THF). Time-dependent (TD) DFT calculations show that the HOMOs of 1-3 are much more destabilized than that of the enamine-containing 4, which confirms the stronger donating ability of NHOs.

SUBMITTER: He J

PROVIDER: S-EPMC6899742 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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N-Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D-π-A Compounds.

He Jiang J Rauch Florian F Friedrich Alexandra A Sieh Daniel D Ribbeck Tatjana T Krummenacher Ivo I Braunschweig Holger H Finze Maik M Marder Todd B TB

Chemistry (Weinheim an der Bergstrasse, Germany) 20190926 60

N-heterocyclic olefins (NHOs), relatives of N-heterocyclic carbenes (NHCs), exhibit high nucleophilicity and soft Lewis basic character. To investigate their π-electron donating ability, NHOs were attached to triarylborane π-acceptors (A) giving donor (D)-π-A compounds 1-3. In addition, an enamine π-donor analogue (4) was synthesized for comparison. UV-visible absorption studies show a larger red shift for the NHO-containing boranes than for the enamine analogue, a relative of cyclic (alkyl)(ami ...[more]

PMID: 31471986

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Dataset Information

N-Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D-?-A Compounds.

Publications

N-Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D-π-A Compounds.

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