- Award ID(s):
- 1954751
- NSF-PAR ID:
- 10343384
- Date Published:
- Journal Name:
- Chemical Communications
- ISSN:
- 1359-7345
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The synthesis and characterization of (tBuPBP)Ni(OAc) (
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Abstract The synthesis and characterization of (tBuPBP)Ni(OAc) (
5 ) by insertion of carbon dioxide into the Ni−C bond of (tBuPBP)NiMe (1 ) is presented. An unexpected CO2cleavage process involving the formation of new B−O and Ni−CO bonds leads to the generation of a butterfly‐structured tetra‐nickel cluster (tBuPBOP)2Ni4(μ‐CO)2(6 ). Mechanistic investigation of this reaction indicates a reductive scission of CO2by O‐atom transfer to the boron atom via a cooperative nickel‐boron mechanism. The CO2activation reaction produces a three‐coordinate (tBuP2BO)Ni‐acyl intermediate (A ) that leads to a (tBuP2BO)−NiIcomplex (B ) via a likely radical pathway. The NiIspecies is trapped by treatment with the radical trap (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) to give (tBuP2BO)NiII(η2‐TEMPO) (7 ). Additionally,13C and1H NMR spectroscopy analysis using13C‐enriched CO2provides information about the species involved in the CO2activation process.