Scope of the N-alkylation of amides and the C-alkylation of malonates by methyl formate and dimethyl carbonate

1993 ◽  
Vol 84 (2) ◽  
pp. L131-L136 ◽  
Author(s):  
A.Ben Taleb ◽  
G. Jenner
Keyword(s):  
Dimethyl Carbonate ◽  
Methyl Formate

Comparison of Promising Sustainable C1-Fuels Methanol, Dimethyl Carbonate, and Methyl Formate in a DISI Single-Cylinder Light Vehicle Gasoline Engine

2021 ◽  
Author(s):  
Sebastian Blochum ◽  
Felix Fellner ◽  
Markus Mühlthaler ◽  
Martin Härtl ◽  
Georg Wachtmeister ◽  
...  
Keyword(s):  
Dimethyl Carbonate ◽  
Methyl Formate ◽  
Gasoline Engine ◽  
Single Cylinder ◽  
Light Vehicle

Calculations on the Non-Classical β-Hydride Elimination Observed in trans-(H)(OMe)-Ir(Ph)(PMe3)3: Possible Production and Reaction of Methyl Formate

2020 ◽  
Author(s):  
Mohamad Ataya ◽  
Faraj Hasanayn
Keyword(s):  
Density Functional ◽  
Dimethyl Carbonate ◽  
Methyl Formate ◽  
Coupling Reaction ◽  
Outer Sphere ◽  
Functional Theory ◽  
Dehydrogenative Coupling ◽  
Square Planar ◽  
Hydride Elimination ◽  
Sphere Mechanism

The octahedral trans hydrido-alkoxide complex trans-(H)(OMe)-Ir(Ph)(PMe<sub>3</sub>)<sub>3</sub> (<b>2</b>-OCH<sub>3</sub>) was prepared by Milstein and coworkers by addition of methanol to Ir(Ph)(PMe<sub>3</sub>)<sub>3</sub> (<b>1</b>). <b>2</b>-OCH<sub>3</sub> was discovered to undergo a methanol catalyzed outer-sphere carbonyl de-insertion in which a vacant coordination site is not required. The reaction yields the octahedral trans dihydride complex <i>trans</i>-(H)<sub>2</sub>-Ir(Ph)(PMe<sub>3</sub>)<sub>3</sub> (<b>2</b>-H) as a kinetic product along with formaldehyde derivatives reported as [CH2=O]<sub>x</sub>. We investigate the mechanism and products of this reaction using density functional theory. The de-insertion transition state has an ion-pair character leading to a high barrier in benzene continuum: ΔG<sup>‡</sup> = 27.9 kcal/mol. Adding one methanol molecule by H-bonding to the alkoxide of <b>2</b>-OCH<sub>3</sub> lowers the barrier to 22.7 kcal/mol. When the calculations are conducted in a methanol continuum, the barrier drops to 8.8 kcal/mol. However, the thermodynamics of de-insertion are endergonic by near 5 kcal/mol in both benzene and methanol. The calculations identify a low energy outer-sphere H/OMe metathesis pathway that transforms the formaldehyde and another <b>2</b>-OCH<sub>3</sub> molecule directly into a second <b>2</b>-H complex and methyl formate. Likewise, a second H/OCH<sub>3 </sub>metathesis reaction interconverting methyl formate and 2-OCH<sub>3</sub> into <b>2</b>-H and dimethyl carbonate is computed to be exergonic and kinetically facile. These results imply that the production of methyl formate and dimethyl carbonate from <b>2</b>-OCH<sub>3</sub> is plausible in this system. The net transformation from the square planar <b>1</b> and methanol to <b>2</b>-H and either methyl formate or dimethyl carbonate would represent a unique stoichiometric dehydrogenative coupling reaction taking place at room temperature by an outer-sphere mechanism.

Bis(dimethoxymethyl) peroxide and bis(1,1-dimethoxyethyl) peroxide

1987 ◽  
Vol 65 (10) ◽  
pp. 2350-2355
Author(s):  
Karl R. Kopecky ◽  
José Molina
Keyword(s):  
Hydrogen Peroxide ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nuclear Magnetic Resonance Spectrum ◽  
Dimethyl Carbonate ◽  
Methyl Formate ◽  
Resonance Spectrum ◽  
Pyridine Solution ◽  
Alkoxy Groups ◽  
Oxygen Bond

The title compounds 1 and 2, the first examples of peroxides polysubstituted at the α and α′ positions by alkoxy groups, are formed by benzophenone sensitized photooxygenation of trimethoxymethane and 1,1,1-trimethoxyethane, respectively. No peroxide was formed from tetramethoxymethane. Allowing 98% hydrogen peroxide and trimethoxymethane to stand results in an 80% yield of 1, so that 1 and 2 are probably formed by such a disproportionation reaction during photooxygenation. Compound 1 is converted quantitatively to methanol, methyl formate, and dimethyl carbonate in pyridine solution at 60 °C. In acidic methanol both 1 and 2 undergo solvolysis rapidly with exclusive cleavage of the carbon – peroxy oxygen bond. Signals for the ether and peroxy oxygens of 1 appear at 34 and 263 ppm and those of 2 appear at 40 and 264 ppm in the 17O nuclear magnetic resonance spectrum. Luminescence results when 1 and 2 are heated to 150 °C.

Comparison between Electron Yield, PSD Ion Yield, and Surface Pipico Yield in Near C and O K-Edge XAFS in Condensed Methyl Formate-D

1997 ◽  
Vol 7 (C2) ◽  
pp. C2-505-C2-506
Author(s):  
T. Selriguehi ◽  
H. L. Sekiguchi ◽  
K. Obi ◽  
K. Tanaka
Keyword(s):  
Methyl Formate ◽  
Electron Yield

Synthesis of carbonate esters by carboxymethylation using NaAlO2 as a highly active heterogeneous catalyst

2018 ◽  
Author(s):  
Sreerangappa Ramesh ◽  
Kiran Indukuri ◽  
Olivier Riant ◽  
Damien Debecker
Keyword(s):  
Heterogeneous Catalyst ◽  
Dimethyl Carbonate ◽  
Sodium Aluminate ◽  
High Yield ◽  
Solid Catalyst ◽  
Highly Active ◽  
Aromatic Alcohols ◽  
Green Conditions ◽  
Mixed Carbonate

<p>Sodium aluminate is presented as a highly active heterogeneous catalyst able to convert a range of alcohols into the corresponding mixed carbonate esters, in high yield and under green conditions. The reaction is carried out using dimethyl carbonate both as a reactant and solvent, at 90°C. Allylic, aliphatic and aromatic alcohols are converted in good yields. The solid catalyst is shown to be truly heterogeneous, resistant to leaching, and recyclable. </p>

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