Base hydrolysis products

The complexity of the metabolism of alachlor, acetochlor, butachlor, and propachlor has led to the development of degradation methods capable of hydrolyzing the crop and animal product residues to readily quantitated degradation products. Alachlor and acetochlor metabolites can be hydrolyzed to two major classes of hydrolysis products, one which contains aniline with unsubstituted alkyl groups at the 2- and 6-positions, and the other which contains aniline with hydroxylation in the ring-attached ethyl group. For alachlor and acetochlor, the nonhydroxylated metabolites are hydrolyzed in base to 2,6-diethylaniline (DBA) and 2-ethyl-6-methylaniline (EMA), respectively, and hy-droxylated metabolites are hydrolyzed in base to 2-ethyl-6-(l-hydroxyethyl)aniline (HEEA) and 2-(l-hydroxyethyl)-6-methylaniline (HEMA), respectively. Butachlor is metabolized primarily to nonhydroxylated metabolites, which are hydrolyzed to DEA. Propachlor metabolites are hydrolyzed mainly to A-isopropylaniline (NIPA). The base hydrolysis products for each parent herbicide are shown in Eigure 1. Limited interference studies have been conducted with other herbicides such as metolachlor to confirm that its residues are not hydrolyzed to the EMA under the conditions used to determine acetochlor residues. Nonhydroxylated metabolites of alachlor and butachlor are both hydrolyzed to the same aniline, DEA, but these herbicides are not used on the same crops. 

Figure 1 Base hydrolysis products of chloroacetanilide herbicides...

The base hydrolysis products of 4ab, Sab and 6 were subjected to FARMS. The fragmentation patterns shown in Figure 2 supported the proposal that 4ab and Sab were almost identical to majusculamide C 6 and dolastatin 11 3 and 12 Sa. ... 

PBX-9404 (94% HMX, 3% NC, 3% CEF) was chosen as the base material for hydrolysis, since much of the prior research by LANL was with this explosive formulation. Analysis of the base hydrolysis products required the use of several instruments and techniques including Fourier transform infrared, nuclear magnetic resonance, and mass spectrometers. Product identification included gas, liquid, and solid products. 

Hydrothermal Treatment of Base Hydrolysis Products Hydrothermal treatment has been investigated by LANL as a possible secondary treatment for base hydrolysis products from explosives destruction. Small-scale experiments offered promising results. Larger-scale experiments were required to look more carefully at the feasibility for such a treatment approach. More product analysis and parameter studies were also required. 

Biological Degradation of Base Hydrolysis Products Biological treatment is attractive as another process for treating base-hydrolyzed HE byproducts because it has the potential to completely destroy hazardous byproducts. 

Thermal Decomposition of Base Hydrolysis Products This pilot plant was tested to demonstrate the feasibility of decomposing base hydrolysate, a mixture of sodium nitrite, sodium formate and other constituents. This material is the waste stream from the base hydrolysis process for destruction of energetic materials, being studied by researchers at LANL. The hydrolysate used in this test was from base hydrolysis experiments to destroy PBX-9404. 

The solution will then contain the free acid and the hydrochloride of the base either of these may separate if sparingly soluble. If a sohd crystallises from the cold solution, filter, test with sodium bicarbonate solution compare Section 111,85, (i) and compare the m.p. with that of the original compound. If it is a hydrolysis product, examine it separately. Otherwise, render the filtrate alkahne with sodium hydroxide solution and extract the base with ether if the presence of the unchanged acyl canpound is suspected, extract the base with weak acid. Identify the base in the usual manner (see Section IV, 100). The acid will be present as the sodium salt in the alkaline extract and may be identified as described in Section IV,175. 

Hexafluorophosphoric Acid. Hexafluorophosphoric acid (3) is present under ambient conditions only as an aqueous solution because the anhydrous acid dissociates rapidly to HF and PF at 25°C (56). The commercially available HPF is approximately 60% HPF based on PF analysis with HF, HPO2F2, HPO F, and H PO ia equiUbrium equivalent to about 11% additional HPF. The acid is a colorless Hquid which fumes considerably owiag to formation of an HF aerosol. Frequently, the commercially available acid has a dark honey color which is thought to be reduced phosphate species. This color can be removed by oxidation with a small amount of nitric acid. When the hexafluorophosphoric acid is diluted, it slowly hydrolyzes to the other fluorophosphoric acids and finally phosphoric acid. In concentrated solutions, the hexafluorophosphoric acid estabUshes equiUbrium with its hydrolysis products ia relatively low concentration. Hexafluorophosphoric acid hexahydrate [40209-76-5] 6 P 31.5°C, also forms (66). This... 

Total basicity is measured by standard acid—base titration techniques. The activity divided by the total basicity should be greater than 90%. If it is not, then the Grignard reagent should be checked for unreacted alkyl or aryl haUde, homo-coupled product, hydrolysis products, and oxidation products. 

The hydrolysis of the uranyl(VI) ion, UO " 2> has been studied extensively and begins at about pH 3. In solutions containing less than lO " M uranium, the first hydrolysis product is the monomeric U02(OH)", as confirmed using time-resolved laser induced fluorescence spectroscopy. At higher uranium concentrations, it is accepted that polymeric U(VI) species are predominant in solution, and the first hydrolysis product is then the dimer, (U02)2(0H) " 2 (154,170). Further hydrolysis products include the trimeric uranyl hydroxide complexes (U02)3(0H) " 4 and (1102)3(OH)(154). At higher pH, hydrous uranyl hydroxide precipitate is the stable species (171). In studying the sol-gel U02-ceramic fuel process, O nmr was used to observe the formation of a trimeric hydrolysis product, ((U02)3( -l3-0)(p.2-0H)3) which then condenses into polymeric layers of a gel based on the... 

Physical techniques can be used to investigate first order reactions because the absolute concentrations of the reactants or products are not required. Dixon et. al [3] studied the base hydrolysis of cobalt complex, [Co(NH3)5L]3+, where L = (CH3)2SO, (NH2)2C = O, (CH3)03P = O in glycine buffers. 

Acetochlor and its metabolites are extracted from plant and animal materials with aqueous acetonitrile. After filtration and evaporation of the solvent, the extracted residue is hydrolyzed with base, and the hydrolysis products, EMA and HEMA (Figure 1), are steam distilled into dilute acid. The distillate is adjusted to a basic pH, and EMA and HEMA are extracted with dichloromethane. EMA and HEMA are partitioned into aqueous-methanolic HCl solution. Following separation from dichloromethane, additional methanol is added, and HEMA is converted to methylated HEMA (MEMA) over 12 h. The pH of the sample solution is adjusted to the range of the HPLC mobile phase, and EMA and MEMA are separated by reversed phase HPLC and quantitated using electrochemical detection. 

A. Abbadi, K.F. Gotlieb, J.B.M. Meiberg and H. van Bekkum, New food antioxidant additive based on hydrolysis products of lactose. Green Chemistiy 5 (2003) 47. 

Hydrolysis of polyamide-based formulations with 6 N HC1 followed by TLC allows differentiation between a-aminocaproic acid (ACA) and hexamethylenedi-amine (HMD) (hydrolysis products of PA6 and PA6.6, respectively), even at low levels. The monomer composition (PA6/PA6.6 ratio) can be derived after chromatographic determination of the adipic acid (AA) content. Extraction of the hydrolysate with ether and derivatisa-tion allow the quantitative determination of fatty acids (from lubricants) by means of GC (Figure 3.27). Further HC1/HF treatment of the hydrolysis residue, which is composed of mineral fillers, CB and nonhydrolysable polymers (e.g. impact modifiers) permits determination of total IM and CB contents CB is measured quantitatively by means of TGA [157]. Acid hydrolysis of flame retarded polyamides allows to determine the adipic acid content (indicative of PA6.6) by means of HPLC, HCN content (indicative of melamine cyanurate) and fatty acid (indicative of a stearate) by means of GC [640]. Determination of ethylene oxide-based antistatic agents... 

Studies of the base-hydrolysis mechanism for hydrolysis of technetium complexes have further been expanded to an octahedral tris(acetylacetonato)techne-tium(III) [30], Although a large number of studies dealing with base hydrolysis of octahedral metal(III) complexes have been published [31], the mechanism of the tris(acetylacetonato)metal complex is still unclear. The second-order base hydrolysis of the cationic complex tris(acetylacetonato)silicon(IV) takes place by nucleophilic attack of hydroxide ion at carbonyl groups, followed by acetylacetone liberation, and finally silicon dioxide production [32], The kinetic runs were followed spectrophotometrically by the disappearance of the absorbance at 505 nm for Tc(acac)3. The rate law has the following equation ... 

A gas liquid chromatographic (GLC) method was described for determining residues of Bayer 73 (2-aminoethanol salt of niclosamide) in fish muscle, aquatic invertebrates, mud, and water by analyzing for 2-chloro-4-nitroaniline, a hydrolysis product of Bayer 73 [83]. Residues were extracted with acetone-formic acid (98 + 2), and partitioned from water samples with chloroform. After sample cleanup by solvent and acid base partitioning, the concentrated extract was hydrolyzed with 2N NaOH and H202 for 10 min at 95°C. The 2-chloro-4-nitroaniline was then partitioned hexane ethyl ether (7 + 3) and determined by electron capture GLC. Average recoveries were 88% for fish, 82% for invertebrates, 82% for mud, and 98% for water at 3 or more fortification levels. 

Synthetic use can be made of the potent electrophilic properties of ADC compounds by transforming the initial adducts into heterocyclic products. For example, reaction of DEAZD with enamine 92 gives the substitution product 93 in quantitative yield. Further treatment of this initial adduct with acid, followed by base hydrolysis leads to benzoxazol-2-ones. The dimethyl substituted enamine (92, R = Me) gives the rare, but isolable 6//-benzoxazol-2-one ring system (Scheme 13).147... 

The hydrolysis products of [PtCl2(amine)2] type of compounds undergo acid-base equilibria shown in Scheme 1. The pK3 values of various Pt(13) compounds are given in Table 2. Comparison of the data for aquated cis- and trans-DDP shows that the p/sfa values for the trans isomer are about one logarithmic unit smaller in the case of diaqua and chlo-roaqua species. By contrast, practically similar pA values have been reported for the monoaquamonohydroxo species of these isomers. 

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