Methanol, production yield

J. H. Baxendale and P. Wardman, THe Radiolysis of Methanol Product Yields, Rate Constants, and Spectroscopic Parameters of Intermediates, NSRDS-NBS54, National Bureau of Standards, U.S. Government Printing Office, Washington, D.C., 1975. 

The filtrate is diluted with 140 ml of 50% methanol-water and placed in the refrigerator for 3 days. The thick sheet of crystalline material which forms on the surface is removed by filtration and washed with 75 % acetic acid to yield 32.5 g of crude product. The filtrate is again cooled overnight and an additional 8.7 g of solid is removed. The crops are combined and the material, mp 120-124°, which is highly colored due to chromium salts, is recrystallized twice from methanol to yield 27 g (24 %) of the keto acid (69) mp 127-129° 78° (CHCI3). 

In about 250 cc of liquid ammonia (cooled with dry ice and acetone) are dissolved about 7.5 g of potassium and into the solution acetylene is passed until the blue color has disappeared (about 3 hours). Then slowly a solution or suspension of 3 g of estrone in 150 cc of benzene and 50 cc of ether is added. The freezing mixture is removed, the whole allowed to stand for about 2 hours and the solution further stirred overnight. Thereupon the reaction solution is treated with ice and water, acidified with sulfuric acid to an acid reaction to Congo red and the solution extracted five times with ether. The combined ether extracts are washed twice with water, once with 5% sodium carbonate solution and again with water until the washing water is neutral. Then the ether is evaporated, the residue dissolved in a little methanol and diluted with water. The separated product is recrystallized from aqueous methanol. The yield amounts to 2.77 g. The 17-ethiny I-estradiol-3,17 thus obtained melts at 142°C to 144°C . 

Dimethyl 4-ethoxy-2,7-dimethyl-4,5-dihydro-l 7/-azepine-3,6-dicarboxylate (1) with sodium ethoxide in refluxing diethyl ether, or on standing at room temperature in carbon tetrachloride solution, readily loses ethanol to yield dimethyl 2,7-dimethyl-4//-azepine-3,6-dicar-boxylate (2).29 The 4-methoxy derivative is also unstable and on warming at 100 C under reduced pressure loses methanol to yield the same product (44%).120... 

Addition of sodium hydroxide to a mixture of [Co"(DMG)2] and an alkylating agent in methanol-water yields up to 50% of the organocobalt product. This appears to be the most convenient method for the preparation of organocobalt(III) derivatives, provided that the maximum yield is not required 161,163). Methods involving the reaction of Co with electrophiles are, at least with DMG complexes, more convenient than the main alternative route via Co(III) and Grignard reagents. 

In this section, we present results of potentiodynamic DBMS measurements on the continuous (bulk) oxidation of formic acid, formaldehyde and methanol on a Pt/ Vulcan catalyst, and compare these results with the adsorbate stripping data in Section 13.3.1. We quantitatively evaluate the partial oxidation currents, product yields, and current efficiencies for the respective products (CO2 and the incomplete oxidation products). In the presentation, the order of the reactants follows the increasing complexity of the oxidation reaction, with formic acid oxidation discussed first (one reaction product, CO2), followed by formaldehyde oxidation (two reaction products) and methanol oxidation (three reaction products). 

Jusys Z, Kaiser J, Behm RJ. 2003. Methanol electrooxidation over Pt/C fuel cell catalysts— Dependence of product yields on catalyst loading. Langmuir 19 6759-6769. 

We found subsequently that MeOH/KOH media at 400°C were very effective reducing systems, as Table IV shows (lb). The methanol work yielded products with significant reductions in organic sulfur levels and moderate reductions in nitrogen levels. We suggest the mechanism of reduction is ionic in nature, involving hydride transfer. Thus... 

Grieco and coworkers have independently described the same type of Pictet-Spengler cyclization reactions involving tryptophan methyl ester and aldehydes, but using methanol as solvent and hydrochloric acid as a catalyst (microwave irradiation, 50 °C, 20-50 min) [416], Moderate to good product yields were obtained. 

Hirano, A., Hon-Nami, K., Kunito, S., Hada, M., and Ogushi, T. (1998). Temperature Effect on Continuous Gasification of Microalgal Biomass Theoretical Yield of Methanol Production and its Energy Balance, Catalysis Today 45. pp. 399-404. 

Partial dehydrogenation of methanol can yield formaldehyde and this can potentially react with itself or unconverted methanol to yield another commonly reported by-product of methanol decomposition, methyl formate 1,12... 

Wentrup and co-workers investigated the flash vacuum pyrolysis of isopropylidene (l-methyIpyrrolidin-2-ylidene)malonate (1261) (86CC369) (Scheme 51). When the pyrolysis was carried out at 450°C (10-4 torr, contact time 10 3 sec), and the product was condensed on a cold finger at -196°C, (pyrrolidinylidene)malonic anhydride (1262) could be identified. Malonic anhydride (1262) in chloroform solution at -20°C lost carbon dioxide to give methyleneketene (1263), which was reacted with a few drops of water or methanol to yield acrylates (1264). Flash vacuum pyrolysis of 1261 at higher temperature (800°C) gave pyrrolopyrrolone (1265). The products were characterized by IR and 13C-NMR data. 

An additional contributing factor to the mechanism of the present grafting reaction is the role of radiolytically produced hydrogen atoms. In the radiolysis of binary mixtures of aromatic and aliphatic compounds such as styrene-methanol, the concentration of aromatic strongly influences the G(H2) obtained from the methanol. In the most extensively studied binary mixtures of benzene-methanol (11) and pyridine-methanol (10), it is found that the yield of H atoms is important in determining product yields and types. Small additions (5%) of benzene and pyridine significantly reduce G(H2) from the methanol by scavenging H atoms. Above 5% additive, G(H2) is reduced further, but at a slower rate. These data for benzene-methanol and pyridine-methanol can be extrapolated... 

H-l,3-ditellurole. Under an atmosphere of argon, 0.23 g (2.4 mmol) of trimethylsily-lacetylene are dissolved in 5 mL dry tetrahydrofuran. The solution is cooled to -70°C. n-Butyl lithium (1.0 mL, 2.4 M, 24 mmol) is dropped into the stirred solution. Then 0.20 g (2.0 mmol) of tellurium powder is added. The mixture is warmed to 20°C and kept at this temperature for 2 h. To this mixture, cooled again to -70°C, is added a solution of 0.35 g (2.0 mmol) of chloroiodomethane in 1 mL of tetrahydrofuran. The mixture is stirred for 15 min and then quenched with 50 mL water. The product is extracted with three 15 mL portions of dichloromethane. The combined extracts are washed with brine, dried with anhydrous sodium sulphate and filtered. The filtrate is concentrated to give trimethylsilylethynyl chloromethyl tellurium as a pale-yellow oil. Tellurium powder (0.125 g, 1.0 mmol) is added to 2 mL of a 1 M solution (2.0 mmol) of lithium triethylborohydride in ethanol. The mixture is stirred at 20°C for 2 h under an atmosphere of argon. Then 2 mL of 1 M sodinm ethoxide in ethanol are added followed by 0.27 g (1.0 mmol) of trimethylsilylethynyl chloromethyl tellurium dissolved in 2 mL dimethylformamide. The mixture is stirred for 15 h at 20°C, then diluted with 25 mL water and extracted with three 15 mL portions of dichloromethane. The combined extracts are dried with anhydrons sodinm snlphate, fdtered and the filtrate concentrated. The residue is chromatographed on silica gel with hexane/dichloromethane (1 1) as mobile phase. The fractions containing the prodnct are concentrated and recrystallized from methanol 65% yield, m.p. 85°C. 

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