Phenol, 5-Bromo-2-nitro

Nitro alcohols were reduced to amino alcohols by catalytic hydrogenation over platinum [632] and with iron [JJ9], and nitrosophenols [255] and nitro-phenols [256] to aminophenols with sodium hydrosulfite, sodium sulfide [238] or tin [176]. Bromine atoms in 2,6-di-bromo-4-nitrophenol were not affected [176]. 

The first, path (1), was straightforward since all N-aminohet-erocycles used in this work (Table V) were known, and methods for their preparation have been published. The majority of the sub-stituted-benzaldehydes used in this method were prepared according to the Beech (17) method as described (18) for the conversion of 2-bromo-4-toluidine into 2-bromo-4-methylbenzaldehyde. The method is of wide application and gave substituted benzaldehydes in 50-75% yield. The unavailability of certain (polyfluoroalkoxy)anilines precluded synthesis of corresponding aldehydes via this method. These were prepared from anisic acids (Chart III) or reduction of nitro-phenols. For example, conversion of meta-anisic acid into 3-(tri-... 

Bromo.4-inethyl-3-nitro phenol (2-Bromo-3-nitro-p-c resol) 77, yel, w 81 Me eth, 74... 

Bromo-2-niethyl-4-nitro-phenol (6-Bromo-4-nitro-o-creso )... 

A series of twenty-nine substituted phenols (e.g., alkyl, phenyl, lluoro, diloro, bromo, nitro, and multisubstituted) was studied using a diol column and a 50/50 chloroform/iso-octane mobile phase [611]. In general, retention increased as the polar nature of the solute increased (e.g., in order of increasing retention 2,4,6-tributylphenol < 4-amylphenol < 4-methylphenol < phenol < 4-chlorophenol < 4-nitrophenol). As might be expected, this system showed good isomer selectivity (A for 3-nitrophenol = 4.20, for 4-nitrophenol = 5.50). However this selectivity was not as pronounced as that found using an underivatized silica support. 

Sodium nitrite I acetic acid Amino- from bromo- ia nitro-phenols... 

Phenol, 4-cyano-Phenol, 3-nitro-Phenol, 2-methyl-Phenol, 3-chloro-Phenol, 4-bromo-Phenol, 2-methyl-4,6-dinitro-Phenol, 2,6-dibromo-4-cyano-(3,5-Dibromo-4-hydroxybenzonitrile) Phenol, 4-tert-butyl-Phenol, 2,4,6-tribromo-Phenol, 2-sec-butyl-4,6-dinitro-Phenol, 2-tert-butyl-4,6-dinitro-Phenol, pentachloro-... 

Phenol B.P. M.P. Bromo Com. pound Acetate Benzoate p-NItro benzoate 3 5 D. nltro- benzoate Aryloxy- acetic Acid NN-DI- phenyl- carba- mate N-O- naphthyl carba- mate p-Tolu- enesul- phonate 2 4- Dlnltro- phenyl Ether... 

Mononitrodiazobromobenzoquinone, 0 C6H2(NO )-(Br) N2 mw 244.02, N 17.22%. Three isomers are described in the literature 2-Diazo-4-nitro-6 -bromo-1,2-benzoquinone [called 6-Brom-4-nitro -2-diazo-phenol or 6-Brom-4-nitro-o-chinon-diazid (2) in Ger], yel ndls(from w), dec ca 152-3° was... 

The yields obtained on dominating the following amines further illustrate the wide utilitybf hypophosphorous acid 2,4-diethyl-6-bromoaniliae (70%),89 3-nitro-4-aminophenylarsonic acid (45%),90 3-amino-6-bromo-benzoic acid (75%),13 3,3 -dimethylbenzidine (76-82%),80-81 4-amino-7-chlorohydrindone-1 (85%),91 5-methyl-8-aminoquinoline (72%) 84 o-(/3-phenylethyl)-aniline (XXII) (47%).86 In the last case, when ethanol is used dibenzyl is not obtained instead the products are 9,10-dihydro-phenanthrene (co. 50%) and o-(j8-phenylethyl)-phenol (23%).66... 

Nitro-4-(trifluoromethyl)-phenol 42 (Scheme 17) in reaction with 2-bromo-2-methyl-propionamide in the presence of cesium carbonate and cesium iodide in acetonitrile afforded 2-hydroxy-2-methylpropionamide 43, apparently via derivative 44 as the intermediate [32]. Amide 44, prepared on a circuitous route, on reduction with borane-dimethylsulfide complex, gave amine 45 as the only isolated product. The parent 2-hydroxy-2-methyl-W-(2-... 

Besides MS detection, identification of unknown peaks in GC routine analysis of environmental samples can be aided by the use of correlations between physicochemical parameters and structure of the analytes to predict the retention times. The correlation between the boiling points and the retention times of chloro- and bromo-benzenes and of some chloro- and nitro-substituted phenols was investigated for nonpolar capillary columns and allowed tentative identification of many compounds belonging to these analogous series. ... 

Photoformylation (the photo-Riemer-Tiemann reaction) of phenols (phenol, 2-methyl, 3-methyl, 4-methyl, 4-chloro, 4-bromo, 4-nitro and 4-phenyl phenol) has also been studied by irradiation in chloroform with KOH and pyridine. The yields reported are variable but formylation is reported only to occur in the 2-position ° °. This process involves the addition to phenol of radicals produced from chloroform. An electron transfer mechanism (transfer from excited state phenol to chloroform) is thought to be involved. The radical ion pair eliminates HCl and combination affords the products 232-234 (Scheme 26). The principal product is the ether and this undergoes partial conversion to the formate. The other products formed in low yield are the aldehydes . In another application of the photo-Riemer-Tiemann reaction, this time in cyclodextrin, the phenols can be converted into 4-hydroxybenzaldehydes with high selectivity . ... 

During the second year of UG, simple one step organic synthesis (e.g. preparation of bromo or nitro derivative) and quantitative estimations based on specific reactions (e.g. estunation of phenol/aniline by bromination) are introduced along with qualitative analysis. The qualitative analysis is at micro-scale level and is more complex in UG second year, as compounds with multifunctional groups arc given for analysis. In addition to characterisation, students have to identify the compound by performing the confirmatory tests. 

Phenol B.P. M.P. Bromo Com- pound Acetate Benzoate p-Nitro- benzoate... 

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