Ketones preparation from

By catalytic reduction of a p-unsaturated ketones, prepared from aldehydes by the Claisen - Schmidt reaction (see under Aromatic Aldehydes), for example ... 

Piperitone can be most easily obtained from the higher boiling portions of the oil of E. dives. It combines slowly with sodium-bisulphite, and by repeated agitation for two or three weeks eventually forms crystals in some quantity. A proportion of alcohol assists the combination. The pure ketone prepared from the purified crystals is colourless at first, but on long standing becomes slightly yellowish in tint. It has a burning peppermint-like taste and odour. The formula is... 

The ketone catalyst is readily prepared from D-fructose by ketalization and oxidation. The other enantiomer of this ketone, prepared from L-sorbose,... 

Ketones, preparation from carboxylic acid, 66, 119 8-Lactams, 65, 140... 

Di-n-heptyl ketone and the di-n-heptyl ketone prepared catalytically from l-octanol-2-d were examined in carbon tetrachloride solutions with a cell having a path length of 1.0 mm. The ketone prepared from 1-octa-nol-2-d showed an absorption band characteristic of C-D at 4.63 of di-heptyl ketone. The number of C-D bonds per ketone molecule was estimated to be in the range of 1.0 to 1.5. A more accurate estimate of the C-D content of the ketone would require a reference sample of deuterated ketone, which was not available. 

The sodium salts of the hydrazones of 2-hydroxybenzaldehydes or of 2-hydroxyphenyl methyl ketones, prepared from the phenols and sodium methoxide in methanol, condensed... 

Trimethylsilyl enol ethers proved to be unsuitable substrates due to the ease of hydrolysis to the ketone. Presumably, for the same reason, the yield of the a-azido ketone prepared from 17 dropped to less than 50% on reaction scales larger than 100 mg125. 

The reaction of thiosalicylic acids with A,A-dialkylacetamides with an electron withdrawing group at the 2-position leads to 2-dialkylamino-3-substituted thiochromones. The use of A-alkylated piperidones produces the benzothiopyrano[2,3-Z)]pyridine ring system <05AJC864>. Cyclisation of alkyl 2-mercaptophenyl ketones, prepared from thiosalicylic... 

The proton nmr of a monomeric enamine-ketone prepared from benzoylacetone and m-xylylenediamine,1, shows a internal hydrogen bonding signal at 11.5-13.5. Its nmr signals are listed in Table I. The nmr signals are in agreement with an enamine-ketone structure. 

Alkoxyvinyl trifluoromethyl ketones and -aryl- -methoxyvinyl trifluoromethyl ketones, prepared from the respective acetophenone dimethyl-acetals by reaction with trifluoroacetic anhydride, undergo cyclocondensation with thiosemicarbazide... 

Asymmetric synthesis of a-alkylated ketones and aldehydes Chiral hydra-zones of ketones prepared from 1 on metalation (LDA) and alkylation are converted into ot-alkyl hydrazones of the ketones. The a-alkyl ketones are obtained on ozonolysis or hydrolysis. Optical yields in this conversion are 30-85% and depend on the structures of the ketone and alkylating agents. a-Chiral aldehydes can be obtained in the same way and with similar optical yields. 

Me-PEEK [77,78] methyl-poly(aryl-ether-ether-ketone) prepared from methyl hydroquinone and 4,4 -difluorobenzophenone. 

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