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Updated: May 30, 2025
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
The divergent reactivity of β-diketiminato aluminium hydrides with organophosphoryl compounds
Yi Ding1, Yinghua Ma1, Yongheng Tang1
1School of Chemistry and Chemical Engineering, State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, Ningxia University, Yinchuan 750021, China. yiding@nxu.edu.cn.
Abstract:
The reactions of LAlH2 (L = HC(CMeNAr)2, Ar = 2,6-Pr2C6H3) (1) with diphenylphosphane oxide [Ph2P(O)H], diphenylphosphinamide [Ph2P(O)NH2], and diaryl/alkyl phosphane [(RO)2P(O)H (R = Ph, or Pr)] afford their corresponding compounds with compositions LAl(H)OP(Ph)2 (2), LAl[OP(Ph)2]2 (3), LAl{[N(H)P(O)(Ph)2][OP(Ph)2]} (4), LAl(OPr)2 (5), and LAl(OPh)2 (6), respectively. These reactions probably undergo a process of dehydrogenation coupling, deaminating dehydrogenation coupling, or chain-breaking coupling. It is noteworthy to mention that the reaction of compound 1 with 2 equiv. of Ph2P(O)NH2 results in 4 and its isomer 4a, where both the complexes exhibit different coordination towards the aluminium centre. The structure of 4a is very rare, where the aluminium centre connects with a nacnac ligand as well as with N and O to form a six-membered and a four-membered ring, respectively. All the compounds were well characterized by multinuclear NMR spectroscopy, elementary analysis, and single-crystal X-ray diffraction.
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