Formic acid from methanol

Fomiate (formic acid, from methanol poisoning) Hypoglycemic agents Isonlazid (INH)... 

Production of methyl formate from methanol also leads to the potential produetion of formic acid from methanol [87]. Formic acid is produced commercially as a side produet of the liquid-phase oxidation of w-butane to acetic acid. It has been suggested, however, that new formie acid capacity will best be obtained by hydrolysis of methyl formate because of raw material costs [87]. The methyl formate could be produeed by either the carbonylation or dehydration of methanol according to the technologies discussed previously. 

The first part of the mechanism is a sequential reaction yielding formic acid, and from that point the typical dual path mechanism for formic acid occurs. In fact, it has been proposed that the mechanisms of formic acid and methanol oxidation consist of the same dominating elemental steps [Okamoto et al., 2005]. However, experiments have revealed that the mechanism is much more comphcated than that. 

Henero E, Femandez-Vega A, Feliu JM, Aldaz A. 1993. Poison formation reaction from formic acid and methanol on platinum (111) electrodes modified by irreversibly adsorbed bismuth and arsenic. J Electroanal Chem 350 73-88. 

Oxidation of the adsorbed species resulting from interaction with formaldehyde, formic acid, and methanol, respectively, leads to stripping peaks that are downshifted to more negative potentials. Furthermore, the adsorbate coverage is significantly lower... 

Figure 13.3 Potentiodynamic electrooxidation of (a) formic acid, (b) formaldehyde, and (c) methanol on a Pt/Vulcan thin-film electrode (7 xgpt cm, geometric area 0.28 cm ) in 0.5 M H2SO4 solution containing 0.1 M HCOOH (a), HCHO (b), or CH3OH (c). The potential scan rate was 10 mV s and the electrolyte flow rate was 5 p-L s at room temperature). The top panels show the faradaic current (solid lines), the partial currents for Ci oxidation to CO2 (dashed lines) and for formic acid formation (dash-dotted line), calculated from the respective ion currents, and the difference between the measured faradaic current and the partial current for CO2 oxidation (formic acid oxidation (a), formaldehyde oxidation (b)), or the difference between faradaic current and the sum of the partial currents for CO2 formation and formic acid oxidation (methanol oxidation, (c)) (dotted line). The solid lines in the lower panels in...

However, since the goal of this work was the synthesis of alcohols from olefins via hydrohydroxymethylation (75, 76), little attention was given to developing a shift-catalyst per se. Pettit has recently reexamined some of this work and shown that, by careful control of the pH of the reaction mixture, systems based on either Fe(CO)5 or Cr(CO)6 can be developed for the production of either formic acid or methanol from carbon monoxide and water (77, 78). Each of these latter systems involves the formation of metal hydride complexes consequently, molecular hydrogen is also produced according to the shift reaction [Eq. (16)]. 

Relative extraction efficiencies of polar polymeric neutral, cation, and anion exchange sorbents (HLB, MCX, and MAX) for 11 beta antagonists and 6 beta agonists in human whole blood were probed.109 Initial characterization of MCX and MAX for acidic and basic load conditions, respectively, showed that both the agonists and antagonists were well retained on MCX, while they were recovered from MAX in the wash with either methanol or 2% ammonia in methanol (see Table 1.6). Blood samples were treated with ethanol containing 10% zinc sulfate to precipitate proteins and the supernatants loaded in 2% aqueous ammonium hydroxide onto the sorbents. After a 30% methanol and 2% aqueous ammonia wash, the analytes were eluted with methanol (HLB), 2% ammonia in methanol (MCX), or 2% formic acid in methanol (MAX). The best recoveries were observed with MCX under aqueous conditions or blood supernatant (after protein precipitation) spiked sample load conditions (see Table 1.7). Ion suppression studies by post-column infusion showed no suppression for propranolol and terbutaline with MCX, while HLB and MAX exhibited suppression (see Figure 1.6). 

Fig. 3.38.The IUPAC names of Sudan azo dyes are as follows Sudan 1 = 1— [(2,4-dimethylphenyl)azo]-2-naphtalenol Sudan II = l-(phenylazo)-2-naphtol Sudan III = l-(4-phenylazophenylazo)-2-naphtol Sudan IV = o-tolyazo-o-tolyazo-beta-naphtol and Disperse Orange 13 = 4-[4-(phenylazo)-l-naphtylazo]-phenol. Azo dyes were separated in an ODS column (250 x 2.1 mm i.d. particle size 5 /xm) at 35°C. The isocratic mobile phase consisted of 0.1 per cent formic acid in methanol-0.1 per cent formic acid in water (97 3, v/v). The flow rate was 200 /xl/min. MS conditions were nebulizing and desolvation gas were nitrogen at the flow rates of 50 and 5551/h, respectively electrospray voltage, 3.0 kV cone voltage 25 V source temperature, 110°C desolvation temperature, 110°C. Azo dyes were extracted from the samples by homogenizing 1 g of sample with 10 ml of acetone, then the suspension was centrifuged and an aliquot of 3 ml of supernatant was mixed with 1 ml of deionized water, filtered and used for analysis. LC-ESI-MS/Ms SRM traces of standards and spiked samples are listed in Fig. 3.39. It was found that the detection and quantitation limits depended on both the chemical structure of the dye and the character of the accompanying matrix. LOD and LOQ values in chilli tomato sauce...

Figure 10.4 Typical UHPLC trace of isoflavones from a soy protein extract monitored at 260 nm using a Hypersil Gold C18 column (100 x 2.1 mm 1.9 pm Waters, Milford, MA) and a 0.5-mL/min flow rate (9600 psi) of a linear gradient of 0.1 % aq. formic acid versus methanol/acetonitrile(l l). FL = flavone (internal standard), other details in figure and in text. Concentrations of ISOFLAVONE peaks (pM) D = 17.66, GLY = 6.27, G = 26.49, D-Mal = 16.76, GLY-Mal = 3.62, D-Ac = 5.87, G-Mal = 26.70, DE = 3.37, GLYCITEIN = 1.74, G-Ac = 8.33, GE = 4.36.

Fig. 8.22. Reconstructed ion chromatogram from the CEC—ESI-MS analysis of cefuroxime axetil diastereomers. Column, 900 x 0.05 mm i.d. packed with 3 pm Hypersil ODSA eluent, 5 mmol/1 sodium tetraborate, pH 9.0, 80% acetonitrile applied voltage, 30 kV detection, ESI-MS, 400-700 amu sheath liquid, 0.3% aqueous formic acid, 50% methanol, 10 pl/min injection, electrokinetic, 30 kV, 5 s. (Reproduced from ref. [98] with permission of John Wiley Sons).

This product comes from the esterification reaction of formic acid with methanol according to the following reaction ... 

On using a LiChrosorb RP-18 column and a 5% aqueous formic acid and methanol, Casteele et al." were able to separate 141 flavonoids, ranging from triglycosides to aglycones. 

Whereas acetic acid was formed in good yield from ethane, the analogous formation of formic acid from methane proceeded only in low yield because of the general instability of the latter acid under the reaction conditions. Since formic acid is a much less desirable product from methane than is methanol, the possibility of halting the oxidation of methane at the methanol stage was examined. 

Since the existing analytical method contained phosphate buffer, method conditions needed to be modified for preparative isolation requiring a volatile mobile phase (0.1% formic acid in methanol). The bulk drug substance lot was purified by preparative HPLC using the modified preparative chromatographic conditions. The component of interest eluted from 5-6 minutes and was collected over multiple runs. The fractions containing the impurity were combined and concentrated by evaporation to give a crude oil. The oil was further purified in a final analytical cleanup to afford 1 mg of sample for NMR analysis. 

It has to be said that carbon monoxide species can be formed from a dissociative adsorption of formic acid, formaldehyde, methanol, ethylene glycol, etc. and are species that are formed as those of the first type of distribution. This suggests that the surface structure is an open structure, since dissociative adsorption of the organic molecule requires adjacent free platinum sites and that at the electrochemical-environment interface, once carbon monoxide is formed, there is almost no mobility at all. 

The use of ultrasounds to aid the extraction is another possibility. Phthalates (Abb et al. 2009) and perfluorinated alkanoic acid (PEA) (Kato et al. 2009) determinations have been reported. Ethyl acetate (phthalates) or formic acid with methanol (perfluoroalkyl chemicals) was added to the dust sample, and extraction was performed in an ultrasonic bath at room temperature for 10 min. In the case of phthalates an enrichment step was not carried out to avoid the risk of contamination. Pyrethroids and their metabolites can also been extracted from indoor dust samples by adding methylene chloride followed by sonication for 10 min (Starr et al. 2008). Another option is the combination of Soxhlet extraction with an ultrasonic treatment (Schecter et al. 2009). 

It is well known that formic acid and formaldehyde are formed and dissolved into the solution as by-products in the methanol electro-oxidation [119-121]. SEIRAS studies revealed that both formaldehyde and formic add also provide adsorbed formate on Pt electrodes in their oxidation [32, 33, 122, 123]. To identify the route of formate adsorption, the same experiment was carried out under flow conditions aiming to wash away produced formaldehyde and formic acid from the electrode surface, but no spectral changes were observed. The result suggests that formate is formed directly from methanol on the Pt surface. 

FIGURE 21.4 Recovery of stable-labeled standards spiked in plasma. Color indicates recovery, according to the scale on the right. Abbreviations ACN = acetonitrile FA = 0.1% formic acid MeOH = methanol SPE= solid-phase extraction. OASIS SPE cartridges were all obtained from Waters Corp. and used per manufacturer instructions. 

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