Reaction with magnesium methyl carbonates

Other Reactions. a-Nitroalkanoic acids or thek esters can be prepared (54—56) by treating nitroparaffins with magnesium methyl carbonate, or with triisopropylaluminum and carbon dioxide. These products are reduced readily to a-amino acids. 

Ketones of the form RCOCH3 and RCOCH2R can be carboxylated indirectly by treatment with magnesium methyl carbonate 52.613 Because formation of the chelate 53 provides the driving force of the reaction, carboxylation cannot be achieved at a disubstituted a position. The reaction has also been performed on CH3N02 and compounds of the form RCH2N02614 and on certain lactones.61s Direct carboxylation has been reported in a number of instances. Ketones have been carboxylated in the a position to give (3-keto acids.616 The base here was lithium 4-methyl-2,6-di-f-butylphenoxide. 

Carboxylation of resorcinols. The acidity of the aromatic hydrogens in resorcinols prompted Israeli chemists4 to investigate the possibility of carboxylation with magnesium methyl carbonate. The reaction was successful. Thus resorcinol gave /3-resorcylic acid (45%) and 2,4-dihydroxyisophthalic acid (15%), together with starting material (43%). 

It is of interest to synthetic chemists and biochemists that the reverse of the reaction shown above, namely, a carboxylation, can be carried out by the treatment of nitromethane with magnesium methyl carbonate, (CHaOMgOCChCHs and CO2), in dimethylformamide. A magnesium chelate of the nitroacetate dianion is formed which, when hydrolyzed under acid conditions, gives nitroacetic acid. The success of this carboxylation of a nitroparaffin depends on the formation of the magnesium chelate, which was identified spectrophotometrically (37, 84, 194) ... 

Alternatively, methane can be manufactured by the reaction of carbon monoxide and hydrogen in the presence of a nickel catalyst. Methane also is formed by reaction of magnesium methyl iodide (Grignard s reagent) in anhydrous ether with substances containing the hydroxyl group. Methyl iodide (bromide, chloride) is preferably made by reaction of methyl alcohol and phosphorus iodide (bromide, chloride). 

The properties of 1,1-dichloroethane are Hsted ia Table 1. 1,1-Dichloroethane decomposes at 356—453°C by a homogeneous first-order dehydrochlofination, giving vinyl chloride and hydrogen chloride (1,2). Dehydrochlofination can also occur on activated alumina (3,4), magnesium sulfate, or potassium carbonate (5). Dehydrochlofination ia the presence of anhydrous aluminum chloride (6) proceeds readily. The 48-h accelerated oxidation test with 1,1-dichloroethane at reflux temperatures gives a 0.025% yield of hydrogen chloride as compared to 0.4% HCl for trichloroethylene and 0.6% HCl for tetrachloroethylene. Reaction with an amine gives low yields of chloride ion and the dimer 2,3-dichlorobutane, CH CHCICHCICH. 2-Methyl-l,3-dioxaindan [14046-39-0] can be prepared by a reaction of catechol [120-80-9] with 1,1-dichloroethane (7). 

A solution of 6-chloro-3,4-dihydro-4-methyl-3-oxo-2H-l,4-benzoxazine-8-carboxylic acid in tetrahydrofuran and dimethylformamide is cooled to below 0°C and triethylamine is added under stirring thereto. Further, ethyl chlorocarbonate is added and the mixture is stirred at room temperature. To the resultant mixture is added 3-amino-8-azabicyclo[3.2.1]octane and the mixture stirred. After completion of the reaction, aqueous sodium hydrogen carbonate and ethyl acetate are added. The organic layer is separated, washed with water and dried over magnesium sulfate. The solvent is distilled off to give 6-chloro-3,4-dihydro-4-methyl-N-(8-azabicyclo[3.2.1]oct-3-yl)-3-oxo-2H-l,4-benzoxazine-8-carboxamide. 

The oil described above was utilized directly in the condensation reaction with the epichlorohydrin. A mixture of 0.1 mole of methyl 3-(4-hydroxyphenyl)propionate, 0.2 mole potassium carbonate and 0.4 mole epichlorohydrin in 250 mL acetone was heated to reflux for 24 hours. The reaction medium was then filtered and evaporated. The residue was taken up in 100 mL toluene and washed with 100 mL 1.0 N NaOH and 100 mL water (2 times). The toluene phase was then dried over magnesium sulfate and evaporated to provide the crude product as an oil. Purification was effected by vacuum distillation (156°C/0.4 mm) and provided methyl 3-[4-(2,3-epoxypropoxy)phenyl]propionate. The NMR and IR spectra and elemental analysis data were consistent with the assigned structure. 

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