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Hydroxy compounds, with halides

Methyl-4-hydroxyquinazoline reacts with organic halides, in the presence of sodium methoxide, to give 3-substituted 2-methyl-4(3i/)-quinazolinones. The 0-acetyl derivative of 4-hydroxyquinazoline has been prepared under anhydrous conditions and gives the hydroxy compound with water or with lithium aluminum hydride. The N-3 acetyl derivative, however, is more stable and gives 3-methyl-4(31/)-quinazolinone with lithium aluminum hydride. ... [Pg.267]

In many cases, substituents linked to a pyrrole, furan or thiophene ring show similar reactivity to those linked to a benzenoid nucleus. This generalization is not true for amino or hydroxyl groups. Hydroxy compounds exist largely, or entirely, in an alternative nonaromatic tautomeric form. Derivatives of this type show little resemblance in their reactions to anilines or phenols. Thienyl- and especially pyrryl- and furyl-methyl halides show enhanced reactivity compared with benzyl halides because the halogen is made more labile by electron release of the type shown below. Hydroxymethyl and aminomethyl groups on heteroaromatic nuclei are activated to nucleophilic attack by a similar effect. [Pg.69]

Reaction of methylmagnesium halide with the 6-ketones (26), (27) and (28) yields the 6a-methyl-6/ -hydroxy compounds. [Pg.59]

Reductive amination of dihydropyran (which may be regarded as the dehydration product of the cyclic acetal of 5-hydroxy-pentanal) in the presence of isopropylamine and a trace of acid affords the aminoalcohol, 96. Treatment of this compound with thionyl chloride affords the haloamine, 97. Alkylation of the quinoline, 92, with this halide yields pentaquine (98). ... [Pg.346]

The A-(l-acyloxyalkyl)amides or carbamates arc easily prepared from the corresponding hydroxy compounds by conventional acylation methods, such as heating with the required carboxylic acid in the presence of a strong acid or treatment with acyl halides or acid anhydrides1. [Pg.813]

Tertiary and aromatic nitroso compounds react with aryl Grignard or aryl-lithium reagents giving the corresponding hydroxylamines . This reaction is useful for preparation of alkyl- and aiylhydroxylamines (e.g. 109, equation 80 and 110, equation 81) and can be considered as complementary to arylation of hydroxy lamines with activated aryl halides. It has been used for functionalization of cyclophanes with the hydroxy amino group. The main limitation of the reaction is the relatively restricted choice of available aliphatic nitroso components, so most of reactions were done with 2-nitroso-2-methylpropane. There is no literature data about the possibility of removal of the tert-butyl group from these compounds. [Pg.143]

Four-Ring Fused Nonaltemant Hydrocarbons under Polycyclic Hydrocarbons, Nonaltemant Compounds with Four Fused Rings Freon 111 under Saturated Alkyl Halides Freon 113 under Saturated Alkyl Halides Fused-Ring Hydroxy Compounds... [Pg.1267]

The most general and useful application of sulfur tetrafluoride is replacement of carbonyl oxygen and hydroxy groups by fluorine. The reaction has broad scope and is effective with all carbonyl and hydroxy compounds. Alcohols are converted into monofluoro derivatives 1, aldehydes, ketones and quinones into gew-difluoro compounds 2 and 3, and carboxylic acids, acid anhydrides, acid halides and amides into trifluoromethyl compounds 4. [Pg.324]

The synthesis of the allyl ethers in nitrogen heterocyclic systems presents an element of complication in that the allylation could occur on the oxygen atom or the basic nitrogen atom. This is a feature of alkylation of ambident anions.3 However, this applies only when the allylation is effected by reacting the oxo or hydroxy derivative of the compound with an allyl halide in the presence of a base.3 The alternative method is to react the appropriate halo derivative with sodium allyloxide in allyl alcohol. The latter approach provides not only better yields of the allyl ethers but also certainty of the constitution of the ethers obtained. A diagnostic tool in deciding between the 1-allyl derivative and the O-allyl compound that has commonly been employed is the infrared absorption of the amide carbonyl in the case of the former which is clearly absent in the latter. [Pg.144]

The aromatic cyanates are of much more importance. If phenols are treated with cyano halides in such a way as to definitely prevent an excess of the corresponding phenolate, aryl cyanates can be isolated in up to quantitative yields. To achieve this, triethylamine is slowly added to an equimolar mixture of the phenol and the cyano halide in a nonprotic solvent, preferably acetone or n-pentane/diethyl ether (equation 27).Heteioaromatic hydroxy compounds can be treated in the same way. The method fails, however, if various electron-attracting substituents are present, as for instance with 2,4-dinitrophenol or polyhalophenols. ... [Pg.244]

In cases where R is a benzyloxy substituent, the use of strong non-aqueous acids, particularly sulfuric and trifluoroacetic acids, provides a convenient means of preparing the hydroxy quinolines XVII by deben-zylation (1J). The hydroxy compounds may be acetylated by standard techniques to afford XVIII. Formation of the sodium salt of XIV using sodium hydride in DMF, followed by reaction with an alkyl halide, leads to the 3-substituted compounds (XIX). [Pg.43]


See other pages where Hydroxy compounds, with halides is mentioned: [Pg.166]    [Pg.428]    [Pg.231]    [Pg.159]    [Pg.888]    [Pg.189]    [Pg.41]    [Pg.564]    [Pg.302]    [Pg.888]    [Pg.855]    [Pg.60]    [Pg.35]    [Pg.4]    [Pg.302]    [Pg.159]    [Pg.84]    [Pg.1265]    [Pg.436]    [Pg.438]    [Pg.448]    [Pg.432]    [Pg.115]    [Pg.1205]    [Pg.888]    [Pg.181]    [Pg.399]    [Pg.159]    [Pg.238]    [Pg.128]    [Pg.131]    [Pg.888]    [Pg.121]    [Pg.10]   
See also in sourсe #XX -- [ Pg.141 , Pg.142 , Pg.143 , Pg.144 , Pg.145 ]




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Halides compounds

Hydroxy compounds

Hydroxy-halides,

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