Tetracarbonyl(trifluoromethyl)cobalt(I) [Co(CO)4(CF3)] as a Precursor to New Cobalt Trifluoromethyl and Difluorocarbene Complexes

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• 作者：Daniel J. Harrison ; Alex L. Daniels ; Ilia Korobkov ; R. Tom Baker
• 刊名：Organometallics
• 出版年：2015
• 出版时间：September 28, 2015
• 年：2015
• 卷：34
• 期：18
• 页码：4598-4604
• 全文大小：373K
• ISSN：1520-6041

文摘

An improved synthesis of the known trifluoromethyl cobalt compound Co(CO)₄(CF₃) (1), which gives significantly higher yields than previously reported methods, allows for an investigation of its carbonyl substitution chemistry. Treatment of 1 with P-donor ligands of varying denticity under thermal conditions afforded Co[P(O-o-tolyl)₃](CO)₃(CF₃) (2), Co(DPPE)(CO)₂(CF₃) (3), and Co(P₃)(CO)(CF₃) (4) in high isolated yields [DPPE = Ph₂PCH₂CH₂PPh₂; P₃ = PhP(CH₂CH₂PPh₂)₂]. The new cobalt N-heterocyclic carbene complex Co(SIPr)(CO)₃(CF₃) (5) [SIPr = 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene)] was obtained by phosphine substitution from Co(PPh₃)(CO)₃(CF₃), a known compound efficiently prepared from 1. Additionally, we report the synthesis of two rare cobalt difluorocarbene complexes ([Co] = CF₂) produced by fluoride abstraction from 3 or 4. These results are relevant to our efforts to assess the reactivity of first-row metal perfluoroalkyl and fluorocarbene complexes.