Burnett Stuart, Bourne Connor, Slawin Alexandra M Z, van Mourik Tanja, Stasch Andreas
EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, KY16 9ST, UK.
Angew Chem Int Ed Engl. 2022 Aug 22;61(34):e202204472. doi: 10.1002/anie.202204472. Epub 2022 Jul 11.
The new β-diketimine nacnacH, HC(iPrCNDip) H, Dip=2,6-iPr -C H , was converted to the magnesium(I) complex [{( nacnac)Mg} ] and reaction with 2-adamantanone (OAd) afforded the ketone-1,2-diide complex [{( nacnac)Mg} (μ-OAd)]. The complex contains the first stable dianion of an aliphatic ketone with an electropositive metal and shows an OAd unit with long C-O bond and pyramidal carbon centre. DFT studies reveal an anionic charge on both neighbouring C and O atoms. Reductions of aliphatic ketones with magnesium(I) complexes show that these likely proceed via highly reactive dianions and afforded a 1 : 1 mixture of an alkoxide and an enolate when an enolisable ketone was used, and rapid CH activations reactions, e.g., of stabilising ligand moieties, when non-enolisable ketones were employed.
新型β - 二酮亚胺nacnacH，即HC(iPrCNDip)H，其中Dip = 2,6 - iPr₂ - C₆H₃，被转化为镁（I）配合物[{(nacnac)Mg}₂]，并且与2 - 金刚烷酮（OAd）反应得到酮 - 1,2 - 二碘化物配合物[{(nacnac)Mg}₂(μ - OAd)]。该配合物包含首个与电正性金属结合的脂肪族酮的稳定二价阴离子，并且显示出一个具有长C - O键和金字塔形碳中心的OAd单元。密度泛函理论研究表明相邻的C和O原子上均带有阴离子电荷。用镁（I）配合物还原脂肪族酮表明，这些反应可能通过高反应活性的二价阴离子进行，当使用可烯醇化的酮时，得到醇盐和烯醇盐的1∶1混合物，而当使用不可烯醇化的酮时，则发生快速的C - H活化反应，例如稳定配体部分的反应。
