Hydrogen chloride ketones

Acetic acid formaldehyde-hydrogen chloride Ketones from prim, amines... 

Hydrogen chloride Ketones from enoxysUanes Selective cleavage... 

Peroxyacetic acid hydrogen chloride Ketones from ethylene derivatives... 

The Fischer Indolisation Reaction occurs when the phenylhydrazone of a suitable aldehyde or ketone undergoes cyclisation with loss of ammonia, under the influence of various reagents, such as zinc chloride, ethnnolic hydrogen chloride, or acetic acid. For example, the phenylhydrazone of acetophenone (p. 257) when heated with zinc chloride gives 2 phenylindole. ... 

By the condensation of a nitrile with a phenol or phenol ether in the presence of zinc chloride and hydrogen chloride a hydroxyaryl- or alkoxyaryl-ketone is produced. The procedure is termed the Hoesch reaction and is clearly an extension of the Gattermann aldehyde reaction (Section IV,121). The reaction gives the best results with polyhydric phenols and their ethers with simple monohydric phenols the imino ester hydrochloride is frequently the sole product for example ... 

Thiazole acid chlorides react with diazomethane to give the diazoketone. The later reacts with alcoholic hydrogen chloride to give chloroacetylthiazole (Scheme 16). However, the Wolff rearrangement of the diazoketone is not consistently satisfactory (82). Heated with alcohol in the presence of copper oxide the 5-diazomethylketone (24) gives ethyl 5-thiazoleacetate (25) instead of the expected ethoxymethyl 5-thiazolyl ketone (Scheme 17) (83). 

Anhydrous stannous chloride, a water-soluble white soHd, is the most economical source of stannous tin and is especially important in redox and plating reactions. Preparation of the anhydrous salt may be by direct reaction of chlorine and molten tin, heating tin in hydrogen chloride gas, or reducing stannic chloride solution with tin metal, followed by dehydration. It is soluble in a number of organic solvents (g/100 g solvent at 23°C) acetone 42.7, ethyl alcohol 54.4, methyl isobutyl carbinol 10.45, isopropyl alcohol 9.61, methyl ethyl ketone 9.43 isoamyl acetate 3.76, diethyl ether 0.49, and mineral spirits 0.03 it is insoluble in petroleum naphtha and xylene (2). 

The treatment of 3-acylisoxazoles (438) with hydroxylamine hydrochloride gives furazan ketones (439). On the other hand, furazan ketones (439) rearrange to 3-acylisoxazoles (438) with a loss of hydroxylamine under the influence of a mineral acid. Thus, by refluxing phenacylphenylfurazan with concentrated alcoholic hydrogen chloride, 3-benzoyl-5-phenyl-isoxazole is formed similarly, phenyl(phenacylphenyl)furazan gives 3-benzoyl-3,5-diphenyl-isoxazole (62HC(17)1, p. 35). 

A general method for preparing acetals by treating aldehydes or ketones with the appropriate tetra-alkyl silicate, using dry hydrogen chloride as the catalyst. Helferich and Hausen, Ber. 57, 795 (1924). 

Hexone (methyl isobutyl ketone) sec-Hexyl acetate Hydrazine Hydrogen chloride... 

Subsequently, Beals and Brown expanded the scope of the earlier work from their laboratory to include the tetraoxaquaterene derived from furan and 3-pentanone. Using 3,3-difurylpentane and diethyl ketone in the presence of dry hydrogen chloride gas, the all-ethyl analog of 6 (mp 249°) was obtained in 20% yield. ... 

Thioketals are readily prepared by reaction of saturated 3-ketones with thiols or dithiols in the presence of boron trifluoride or hydrogen chloride catalysts. Selective protection of the 3-ketone in the presence of a 6-ketone is possible by carrying out the reaction in diluted medium. Similarly, 3-ketones react selectively with monothiols " " or with bulky dithiols in the presence of 6-, 7-, 11- and 12-ketones. 

Steroidal 17-cyanohydrins are relatively stable towards chromium trioxide in acetic acid (thus permitting oxidation of a 3-hydroxyl group ) and towards ethyl orthoformate in ethanolic hydrogen chloride (thus permitting enol ether formation of a 3-keto-A system ). Sodium and K-propanol reduction produces the 17j -hydroxy steroid, presumably by formation of the 17-ketone prior to reduction. ... 

The cyclization of 1,3,5-triketones to pyrones will not be discussed here, although this is a related reaction, because pyrones are not true pyrylium salts. Mention will be made, however, of the formation of 2,6-diphenyl-4-pyrone from 1,3-dibenzoylallene this ketone adds secondary amines leading to 3-dialkylamino-l,5-diphenyl-4-penten-l,5-diones, which arc cyclized by hydrogen chloride in acetic acid to 2,6-diphenyl-4-dialkylaminopyrylium chlorides (R = Me and/or Ph) (see Scheme. 5). 

In a first step, the carboxylic acid 1 is converted into the corresponding acyl chloride 2 by treatment with thionyl chloride or phosphorous trichloride. The acyl chloride is then treated with diazomethane to give the diazo ketone 3, which is stabilized by resonance, and hydrogen chloride ... 

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