Synthesis of new functionalized aryl‐substituted methylphosphonic and methylenediphosphonic acids and their derivatives

The convenient syntheses of new aryl‐substituted hydroxymethylphosphonic and methylenediphosphonic acids from the aromatic aldehydes, their derivatives, and phosphorous acid esters in the presence of the effective catalysts (trimethylsilyl trifluoromethanesulfonate, zinc chloride, and cadmium iodide) were developed.     

Quantum chemical interpretation of the effects induced by tetramethylethylenediamine and dimethoxyethane in RLi non-polar monomer systems

The energetic and electronic parameters of various mono- and bidentate complexes of CH₃Li with N- and O-containing electron donors were calculated by the MNDO method. It was shown that N,N,N′,N′-tetramethylethylenediamine (TMD) forms a more stable bidentate complex with CH₃Li than 1,2-dimethoxyethane (DME). However, DME, in contrast to TMD, may form a bis-bidentate complex with CH₃Li in which the C Li bond is weakened to a higher degree than in complexes of CH₃Li with N-containing electron donors. Much lower steric hindrance of DME, as compared to that of TMD, makes an easy formation of bis- and tris-monodentate complexes of DME with CH₃Li possible; in these bis- and tris-monodentate complexes DME was simulated by (CH₃)₂O. Parameters of the C Li bond in the tris-monodentate complexes of (CH₃)₂O and tetrahydrofuran (THF) with CH₃Li are comparable to those of the bis-bidentate complex CH₃Li · 2 DME. These results are in qualitative agreement with experimental data, according to which THF and DME, in contrast to TMD, can favor the formation of separated ion pairs as active sites in anionic polymerization.