F Dimethoxymethane

PC = propylene carbonate DN = 1,3-dioxolane EC = ethylene carbonate 3-MeS-3 = methyl sulfolane DME = dimethoxy ethane THF = tetrahydrofuran S = sulfolane DMSO = dimethyl sulfoxide, DEE = diethyl ether, 2-Me-F = 2 methyl furan 2-MeDN = 2-methyl 1,3-dioxolane MA = methylacetate DMM = dimethoxymethane 2-MeOTHF = 2 methoxytetrahydrofuran BL = y-butyrolactone NM = nitromethane AN = acetonitrile MF = methyl formate DEC = diethyl carbonate DMC = dimethyl carbonate. 

It is remarkable that the rate constant kg of the addition of dimethoxymethane to methoxycarbenium ion/F.6 is only 10 times higher than the rate constant kgx of the identical reaction involving the equivalent oxonium ion/F. 7. 

Under typical polymerization conditions, the total concentration of growing species is e.g. 10 mole F and the concentration of polymer is equal to e.g. 2.5 mole 1. Under these conditions, taking into account the value of Kg = 3 10 mole", we would have 10" mole 1" of oxonium ions (assuming that dimethoxymethane is a suitable model fmonomer molecules converted into polymer, only 10 wouU be added through carbenium ions and the rest throu oxonium ions. The actual data for 1,3-dioxolane are not known at pr nt and may differ from values found for dimethoxymethane. Nevertheless, of primary importance is the finding that the reactivities of alkoxycarbenium ions and tertiary oxonium ions toward linear acetals, expressed through the corresponding rate constants, differ for the discussed above conditions only by 10 times. 

XIII. A qualitative rationalization of the conformational preference in CHjOCHjX, where X = F, SCHj, CH3, NHj, and NHJ, can be advanced along the same lines as for dimethoxymethane and chloromethoxymethane, with the contributions of the dipolar, delocalization, and intrinsic torsional terms. 

DIMETHOXYMETHANE (109-87-5) C3H8O2 Highly flammable liquid. Forms explosive mixture with air extremely low ignition temperature makes it very dangerous [explosion limits in air (vol %) 1.6 to 17.6 flash point-26°F/-32°C oc 0 >F/-18°C J autoignition temp 459°F/237°C Fire... 

DIMETHOXYMETHANE (109-87-5) Forms explosive mixture with air (flash point -26°F/—32°C oc). Forms unstable peroxides in storage. Violent reaction with strong oxidizers. Incompatible with acids. Attacks some plastics, rubber, and coatings. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

For each fixed 0 one can obtain individual Fourier expansions F(0") with respect to rotation described by the dihedral angle 0" this corresponds to a particular section through the energy surface Ej =/( , 0"). If for " = 180° a molecule has a plane of symmetry, it suffices to consider only the first three terms of Eq. [24]. This is the case for fluoromethanol (121) (Figure 20) and dimethoxymethane (11 with 0 fixed at 180°). In addition, when one rotating alkyl group is of C3 symmetry (as is, approximately, CHj in methanol), internal rotation may be adequately described by a simple threefold potential function expressed by Eq. [26]. 

Some olefin complexes may conveniently be obtained by electrochemical reduction methods. Cyclooctadiene and cyclododecatriene nickel(O) complexes such as Ni(COD)2 and Ni(CDT) may be prepared by electrochemical reduction of nickel acetylacetonate in the presence of butadiene in acetonitrile, dimethoxymethane, or DMF solutions. Complexes [Fe(CO)4 (alkene)] are reduced electrochemically to lie compounds [Fe(CO)3 (alkene)] . In the case of complexes [Fe(CO)3 (f/Miene)] (diene = BD, cyclohexadiene), during reduction, lie anions [Fe(CO)3 (diene)] are formed in which one olefin bond is decomplexed. ... 

These include chloroethylene carbonate (Cl-EC), vinylene carbonate (VC), ethylene sulfite (ES), propylene sulfite (PS), fluoroethylene sulfite (EEC), a-bromo-y-butyrolactone, methyl chloroformate, f-butylene carbonate (f-BC), and 12-crown (12-C-4). In addition to these additives, co-solvents, such as dimethylsulfoxide (DMSO), diethoxymethane (DEM), dimethoxymethane (DMM), and diethoxyethane (DEE) are also effective for stable SEI formation in PC-based solutions. The molecular structures of these additives and co-solvents are summarized in Figure 13. It seems that all these additives give stable SEI layers on graphite surface ... 

COM ComeUi, F., Ottani, S., Francesconi, R., and Castellari, C., Densities, viscosities, refractive indices, and excess molar enthalpies of binary mixtures containing poly(ethylene glycol) 200 and 400 + dimethoxymethane and + 1,2-dimethoxyethane at 298.15 K, J. Chem. Eng. Data, 47, 1226, 2002. 

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