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Evaluation of Pd?B Interactions in Diphosphinoborane Complexes and Impact on Inner-Sphere Reductive Elimination.

ABSTRACT: The dative Pd?B interaction in a series of ^R DPB^R' Pd⁰ and Pd^II complexes (^R DPB^R' =(o-PR₂ C₆ H₄ )₂ BR', diphosphinoborane) was analyzed using XRD, ¹¹ B?NMR spectroscopy and NBO/NLMO calculations. The borane acceptor discriminates between the oxidation state Pd^II and Pd⁰ , stabilizing the latter. Reaction of lithium amides with [(^R DPB^R' )Pd^II (4-NO₂ C₆ H₄ )I] chemoselectively yields the C-N coupling product. DFT modelling indicates no significant impact of Pd^II ?B coordination on the inner-sphere reductive elimination rate.

SUBMITTER: Ritter F

PROVIDER: S-EPMC7692930 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Evaluation of Pd→B Interactions in Diphosphinoborane Complexes and Impact on Inner-Sphere Reductive Elimination.

Ritter Florian F John Lukas L Schindler Tobias T Schroers Julian P JP Teeuwen Simon S Tauchert Michael E ME

Chemistry (Weinheim an der Bergstrasse, Germany) 20200918 59

The dative Pd→B interaction in a series of R DPBR' Pd0 and PdII complexes (R DPBR' =(o-PR2 C6 H4 )2 BR', diphosphinoborane) was analyzed using XRD, 11 B NMR spectroscopy and NBO/NLMO calculations. The borane acceptor discriminates between the oxidation state PdII and Pd0 , stabilizing the latter. Reaction of lithium amides with [(R DPBR'</ ...[more]

PMID: 32428264

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