A new diarylmido-based pincer proto ligand ( iPrPNHSbPh ) with one –PPr i 2 and one –SbPh 2 side donor has been synthesized. Three complexes of its amido form were prepared using standard metalation techniques: ( iPrPNSbPh ) PdCl , ( iPrPNSbPh ) RhCO , and ( iPrPNSbPh ) Ir(COE) , where COE = cis -cyclooctene. These complexes were compared with their previously reported analogs incorporating a –PPh 2 side donor in place of –SbPh 2 . The –SbPh 2 donor arm is less donating towards the metal and is less strongly trans -influencing, based on the structural and IR spectroscopic analysis of the Rh complexes. The redox potential of the Pd complexes is only marginally affected by the change from –PPh 2 to –SbPh 2 . (iPrPNSbPh)Ir(COE) proved to be a slower and less selective catalyst in the dehydrogenative borylation of terminal alkynes (DHBTA) than its –PPh 2 analog.
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Distinct modes of Si–H binding to Rh in complexes of a phosphine-diarylamido-silane (SiNP) pincer ligand
Syntheses of Rh complexes of the phosphine-amido-silane SiNP ligand are reported. The reaction of the parent (SiNP)H ligand (4) with 0.5 equiv. [(COE)RhCl] 2 (COE = cis -cyclooctene) in the presence of NaN(SiME 3 ) 2 resulted in the formation of (SiNP)Rh(COE) (5). Compound 5 was converted to a series of (SiNP)Rh(P(OR) 3 ) complexes 6–10 (R = Ph, i Pr, n Bu, Et, or Me) by treatment with the corresponding phosphite. NMR and XRD structural data, as well as the DFT computational analysis indicate that compounds 5–10 are divided into two structural Types ( A and B ), differing in the nature of the interaction of the Si–H bond of the SiNP ligand with Rh.
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- NSF-PAR ID:
- 10410819
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 51
- Issue:
- 37
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 14150 to 14155
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2DT02175G
