論文

査読有り
2018年1月22日

1,2-CH Bond Activation of Pyridine across a Transient Titanium Alkylidene Radical and Re-Formation of the Ti=CHtBu Moiety

Organometallics
  • Takashi Kurogi
  • ,
  • Matthias E. Miehlich
  • ,
  • Dominik Halter
  • ,
  • Daniel J. Mindiola

37
2
開始ページ
165
終了ページ
167
記述言語
掲載種別
研究論文(学術雑誌)
DOI
10.1021/acs.organomet.7b00770

Reduction of the titanium alkylidene [(PNP)Ti=CHtBu(OTf)] (PNP- = N[2-PiPr2-4-methylphenyl]2-) with KC8 in the presence of pyridine results in formation of the transient titanium(III) alkylidene radical [(PNP)Ti=CHtBu)] (A) or the adduct [(PNP)Ti=CHtBu)(NC5H5)] (B), which activates the C-H bond of pyridine to form the titanium(III) pyridyl alkyl complex [(PNP)Ti(CH2tBu)(?2-NC5H4)] (1) in 64% yield as brown microcrystals. Low-Temperature X-band EPR spectroscopy and single-crystal X-ray diffraction studies confirm the identity of 1 as a d1 metal-centric radical with superhyperfine coupling to one nitrogen atom and having a side-on pyridyl moiety, which results in formation of the two isomeric forms 1a,b. Oxidation of 1 with [FeCp∗2][OTf] cleanly promotes α-hydrogen abstraction to re-form [(PNP)Ti=CHtBu(OTf)] with concurrent elimination of pyridine and FeCp∗2. Re-formation of the alkylidene moiety most likely stems from an intermediate such as [(PNP)Ti(CH2tBu)(n2-NC5H4)(OTf)] (C).

リンク情報
DOI
https://doi.org/10.1021/acs.organomet.7b00770
Scopus
https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85040954118&origin=inward
Scopus Citedby
https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85040954118&origin=inward
URL
http://orcid.org/0000-0002-8804-757X
ID情報
  • DOI : 10.1021/acs.organomet.7b00770
  • ISSN : 0276-7333
  • eISSN : 1520-6041
  • ORCIDのPut Code : 41795237
  • SCOPUS ID : 85040954118

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