4’-hydroxyacetophenon

Production is by the acetylation of 4-aminophenol. This can be achieved with acetic acid and acetic anhydride at 80°C (191), with acetic acid anhydride in pyridine at 100°C (192), with acetyl chloride and pyridine in toluene at 60°C (193), or by the action of ketene in alcohoHc suspension. 4-Hydroxyacetanihde also may be synthesized directiy from 4-nitrophenol The available reduction—acetylation systems include tin with acetic acid, hydrogenation over Pd—C in acetic anhydride, and hydrogenation over platinum in acetic acid (194,195). Other routes include rearrangement of 4-hydroxyacetophenone hydrazone with sodium nitrite in sulfuric acid and the electrolytic hydroxylation of acetanilide [103-84-4] (196). 

The Eries rearrangement of phenol esters gives a mixture of 2- and 4-acylphenols (56). The reaction is cataly2ed by Lewis acids such as aluminum chloride or by Brmnsted acids like hydrogen fluoride. This reaction is used in the production of 4-hydroxyacetophenone [99-93-4] a raw material for... 

Figure 3 Illustration of overlapping substrate specificities of four BVMOs. Cyclohexanone monooxygenase (CHMO), cyclopentanone monooxygenase (CPMO), 4-hydroxyacetophenone monooxygenase (HAPMO) and phenylacetone monooxygenase (PAMO). For each enzyme, several typical substrates are...

The degradation of bisphenol-A by Sphingomonas sp. strain AOl is initiated by hydroxylation to intermediates that undergo fission to 4-hydroxyacetophenone and 4-hydroxybenzoate. The components have been purified, and consist of cytochrome P450, ferredoxin reductase, and ferredoxin (Sasaki et al. 2005). 

A formally comparable pathway is used by a strain of Alcaligenes sp. that degrades 4-hydroxyacetophenone to 4-hydroxybenzoyl methanol, which is oxidized in an unusual reaction to 4-hydroxybenzoate and formate. The 4-hydroxybenzoate is then metabolized to 3-ketoadipate via 3,4-dihydroxybenzoate (Figure 8.35b) (Hopper et al. 1985). 

FIGURE 8.35 Degradation of (a) mandelate, (b) 4-hydroxyacetophenone by side-chain oxidation pathways, (c) acetophenone by Baeyer-Villiger monooxygenation. 

Darby JM, DG Taylor, DJ Hopper (1987) Hydroquinone as the ring-fission substrate in the catabolism of 4-ethylphenol and 4-hydroxyacetophenone by Pseudomonas putida Dl. J Gen Microbiol 133 2137-2146. 

Hopper DJ, HG Jones, FA Elmorisi, ME Rhodes-Roberts (1985) The catabolism of 4-hydroxyacetophenone by an Alcaligenes sp. J Gen Microbiol 131 1807-1814. 

Kamerbeek NM, All Olsthoorn, MW Fraaije, DB Janssen (2003) Substrate specificity and enantioselectivity of 4-hydroxyacetophenone monooxygenase. Appl Environ Microbiol 69 419-426. 

C8H9NO2 4 -Hydroxyacetophenone oxime Extraction-photometric Simultaneous Ni Cu, Ni 3... 

Hydroxy-trinitro-acetophenone (called Trinitro-4-oxy-acetophenon in Ger), H0C6H(N02)3C0CH3 mw 271.14, N 15.50%, crysts si sol in hot w.. Prepd by heating 4-hydroxyacetophenone with 1.3 g/cc nitric acid. No explosive props mentioned... 

The test sample to use in qualification should be a small molecule that is soluble in water, has a strong UV chromophore, and possesses a charge at the intended separation pH value. A nonvolatile compound is also desirable, especially when used for assessing peak area reproducibility during the detector linearity test. Some examples of test samples that can be used are benzoic acid, 4-hydroxyphenylacetic acid, 4-hydroxybenzoic acid, and 4-hydroxyacetophenone. 

Figure 12.3. Typical electropherogram from an injection reproducibility test. CE conditions capillary, 50 qm ID x 50 cm (40 cm to detector) temperature, 20°C detection, 325 nm with 10-nm bandwidth injection, 3 s (5 kPa) 1 mM 4-hydroxyacetophenone applied voltage, +30 kV separation buffer, 20 mM borate at pH 9.2 conditioning, 2-min high-pressure rinse (100 kPa) with 20 mM borate buffer pH 9.2 between runs.

Examples of the type of peaks which arise due to absorption by the O-H group can be seen in the IR spectrum of 4 -hydroxyacetophenone (Figure 3.3), in which there are broad O-H peaks centered on 3304 cm" (non-hydrogen bonded) and 3158 cm" (due to hydrogen bonding), and paracetamol (Figure 3.4), in which there is an O-H absorption at 3161 cm". ... 

Figure 5.11 shows the El MS of 4 -hydroxyacetophenone (C8H8O2), with the expected M peak at mfz 136. 

Di-ter2-butylphenol 2,4,5-Trichlorophenol Phenyl salicylate Methyl 4-hydroxybenzoate 4-Hydroxyacetophenone Ethyl 4-hydroxybenzoate 4-Hydroxybenzaldehyde Pentachlorophenol 4-Chloro-2-nitrophenol 4-Nitrophenol... 

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