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Phenol hydrazine

Although periodates also oxidize polycyclic aromatic hydrocarbons, phenols, hydrazines, active methylene compounds and sulfides, chemoselectivity can usually be achieved and glycol cleavage oxidation takes precedence. For example, the diol moiety in the diethyl dithioacetal derivative of o-glucose can be selectively oxidized in good yield (equation 6). In contrast, LTA is less selective dum periodate and oxidizes a far greater variety of oiganic compounds. Consequently, in order to minimize undesired reactions, it is customary to add LTA slowly to avoid contact of die initially formed products widi an excess of the oxidant (equation 7). ... [Pg.710]

Diazonium salts are valuable reagents for the synthesis of aryl halides, nitriles, phenols, hydrazines and azo compounds. [Pg.103]

Azo phenols which are of course the same as hydroxy azo compounds (p. 576), azoxy phenolsy hydrazo phenolsy phenol hydrazines and di-azo phenols are all known either as phenols or as phenol ethers. The last group is interesting historically as the first diazo compound made by Griess was di-nitro phenol diazonium chloride,... [Pg.635]

The highest perchlorate concentration detected was 124 ppb from the Glenbrook Road wells. These weUs also had low levels of RDX and phenol hydrazine. Perchlorates were developed at the AUES in several forms, including their use as a hand grenade filler. Only low levels of perchlorates... [Pg.186]

Storm sewers, springs, and surface creeks all drain into the Potomac River. As yet, significant sampling has not been performed to assess what if any contaminants are entering the river. The little sampling that has been done indicates a problem. Arsenic has been found in stream sediments and in the ephemeral pools along the river. Perchlorate was found in one storm sewer. Phenol hydrazine has been found in groundwater, which presumably enters the river. Thus, aquatic life is a potential receptor. [Pg.226]

FDA-approved tin(II) 2-ethylhexanoate (Sn(EH)2), glucose,ascorbic acid, phenol, hydrazine and phenylhydrazine, excess inexpensive ligands,or selected nitrogen-containing monomers. Cu° also works as a reducing agent in an ARGET ATRP but it increases the level of transition metal halides (CuX and CuXj) in the reaction system due to continuous reduction of Cu formed by tma-voidable termination reactions (Cu° + Cu = 2Cu ). [Pg.382]

In addition to the April 1921 article in the American University Courier previously quoted, other records also indicate that two new explosives were developed at the AUES anihte (a French explosive) and monomethyl hydrazine nitrate. Hydrazine nitrate is the most interesting because it is still the third most powerful explosive known. Phenol hydrazine has been detected in two groundwater samples a mile apart, raising the specter that hydrazine was an explosive that may have been buried in large quantities. Photographs of tests on mono and anilite exist. [Pg.224]

Preliminary indication of the presence of a phenol ester may be obtained by heating the compound with soda-lime esters of phenols and also aromatic hydroxy-acids usually give the phenol. (Likewise amides, Imides, nitriles, substituted hydrazines, uretheines, etc. eifiord ammonia.)... [Pg.1064]

Several methods are available to supplement the phenol alkylations described above. Primary alkylphenols can be produced using the more traditional Friedel-Crafts reaction. Thus an -butylphenol can be synthesized direcdy from a butyl haUde, phenol, and mild Lewis acid catalyst. Alternatively, butyryl chloride can be used to acylate phenol producing a butyrophenone. Reduction with hydrazine (a Wolff-Kishner reduction) generates butylphenol. [Pg.59]

Me3Si)2NH, Me3SiCl, Pyr, 20°, 5 min, 100% yield. ROH is a carbohydrate. Hexamethyldisilazane (HMDS) is one of the most common sily-lating agents and readily silylates alcohols, acids, amines, thiols, phenols, hydroxamic acids, amides, thioamides, sulfonamides, phosphoric amides, phosphites, hydrazines, and enolizable ketones. It works best in the presence of a catalyst such as X-NH-Y, where at least one of the group X or Y is electron-withdrawing. ... [Pg.69]

A solution of bismuth trioxide in hot glacial acetic acid provides a specific method for the oxidation of acyloins. " The reaction rate is dependent on the steric accessibility of the ketol system. A 2,3-ketol requires less than one hour for completion but an 11,12-ketol is not yet fully oxidized in thirty hours." The reaction is highly selective as a-keto acids, hydrazines and phenols are not oxidized. In a direct comparison with cupric acetate, this procedure is somewhat superior for the preparation of a 2,3-diketone from a 2-keto-3-hydroxy steroid. ... [Pg.250]

Toluene from Toluidine.—It is often desirable to obtain tbe hydiocarbon from the base. The process of diazotisntion offers the only convenient method. The diazonium salt may be reduced by alcohol (Reaction 1, p. 162) or, as in the piesent instance, by sodium stannite. Less direct methods are the con-veision of the diazonium compound into (i) the hydrazine (see p. 174), (2) the acid and distillation with lime (p. 200), (3) the halogen derivative and reduction with sodium amalgam, 01, finally (4) the phenol and distillation with zinc dust. [Pg.284]

Reaction of 2,4-dichloro-l,5-naphthyridine with ammonia (170°, 20 hr), hydrazine (100°, 16 hr), or aqueous hydrochloric acid (100°, 3 hr) was shown to yield the 2-amino- (47% yield) and 2-hydroxy-4-chloro derivatives (66% yield), but 2-hydrazino substitution (68% yield) was assumed. Disubstitution with ammonia (190°, 4 hr), hydrazine (100°, 48 hr), and ammonia-phenol (180°, 6 hr) occurred in high yield. Displacement of the 4-oxo group in 2,4-dioxo-l,5-naphthyridine occurs with aniline plus its hydrochloride (180°, 12 hr, 88% yield) to yield 429. Oxo groups in the 2- or 4-positions were... [Pg.378]

The guanidine function, when attached to an appropriate lipophilic function, often yields compounds that exhibit antihypertensive activity by means of their peripheral sympathetic blocking effects. Attachment of an aromatic ring via a phenolic ether seems to fulfill these structural requirements. Alkylation of 2,6-dichlorophenol with bromochloroethane leads to the intermediate, 58. Alkylation of hydrazine with that halide gives 59. Reaction of the hydrazine with S-methylthiourea affords the guanidine, guanoclor (60). ... [Pg.117]

The activation of persulfates by various reductant viz. metals, oxidizable metals, metal complexes, salts of various oxyacid of sulfur, hydroxylamine, hydrazine, thiol, polyhydric phenols, etc. has been reported [36-38]. Bertlett and Colman [39] investigated the effect of methanol on the decomposition of persulfates and proposed the following mechanism. [Pg.486]

A departure from the catechol pattern of the natural neurotransmitters was achieved following application of the fact that arylsulfonamido hydrogens are nearly as acidic as phenolic OH groups. Nitration of p-benzyloxyacetophenone gave 18 which was reduced to 19 with Raney nickel and hydrazine, and in turn reacted with mesyl chloride to give sulfonamide 20. Methanesulfonate 20 was then transformed to soterenol (21), a clinically useful bronchodilator, in the... [Pg.40]

The hydrochloride of 3-amino-4-hydrazinopyridine 65 was prepared by reaction of the 4-chloro-3-nitropyridine derivative with ethoxycarbonyl-hydrazine in phenol to give the hydrochloride of ethyl 3-(3-nitro-4-pyridyl)carbazate 64 (R2 = OEt), which on successive heating in concentrated hydrochloric acid and hydrogenation over Pd/C gave 65. Its reaction with phenylacetic acid or with phenoxyacetic acid gave the hydrochloride... [Pg.217]

Apart from complex formation involving metal ions (as discussed in Chapter 4), crown ethers have been shown to associate with a variety of both charged and uncharged guest molecules. Typical guests include ammonium salts, the guanidinium ion, diazonium salts, water, alcohols, amines, molecular halogens, substituted hydrazines, p-toluene sulfonic acid, phenols, thiols and nitriles. [Pg.138]

A procedure for the preparation of 3,6-bis(4-hydroxyphenyl)-l,2,4,5-tetrazine (48) from phenol 47 and hydrazine has been described <00SC1083>. [Pg.303]

Related (diisopropoxyphosphoryl)- and (diisobutoxyphosphoryl)formonitrile oxides (114), generated in basic media from the corresponding oximes react in situ with alcohols, phenols, alkanethiols, thiophenols, aliphatic and aromatic primary amines, hydrazines and hydrazides as well as 4-aminoantipyryne to give hydroxymates, thiohydroxymates, and amidoximes, respectively. It is important to note that the addition is stereoselective and gives E-adducts with the exception of (i-Pr0)2P(0)C( N0H)0Me, which is formed as a 1 1 mixture of E and Z isomers. [Pg.16]

Enzymatic transformations of alkaloids by peroxidases most probably occur by single-step oxidations catalyzed by the HRP-I and HRP-II forms of the enzyme. The catalysis of one-electron oxidations of compounds containing aromatic hydrocarbon, hydrazine, phenol, hydroxamic acid, and amine functional groups has been recently reviewed (45, 58, 82). A brief summary of those HRP reactions that involve functional groups most commonly occurring in alkaloids is presented below. [Pg.347]


See other pages where Phenol hydrazine is mentioned: [Pg.2434]    [Pg.89]    [Pg.217]    [Pg.249]    [Pg.198]    [Pg.2434]    [Pg.89]    [Pg.217]    [Pg.249]    [Pg.198]    [Pg.49]    [Pg.404]    [Pg.186]    [Pg.238]    [Pg.372]    [Pg.377]    [Pg.379]    [Pg.386]    [Pg.1052]    [Pg.446]    [Pg.43]    [Pg.146]    [Pg.163]    [Pg.94]   
See also in sourсe #XX -- [ Pg.224 , Pg.232 ]




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