Potassium fluoride/ Aluminium oxide

The reaction of the hydroxyallyl ylide Ph3As=CHCH=CHCH20H with benzal-dehyde takes place under phase-transfer conditions and gives a mixture of E and Z 3-hydroxyallyloxiranes it gives a higher yield in acetonitrile in the presence of potassium fluoride and aluminium oxide than in the presence of solid potassium hydroxide . ... 

Basu et al. have reported palladium-catalyzed selective cross coupling of bromo-pyridines and amines on the surface of potassium fluoride supported basic aluminium oxide [5]. For example, amination of 2,6-dibromopyridine by this method afforded the monoaminated products predominantly, even after prolonged the reaction time and using excess amine, whereas previous method [6] gave only bis-aminated products (Scheme 5.3). 

Scheme 5.3 Palladium-catalyzed selective cross coupling of bromopyridines and amines on potassium fluoride supported basic aluminium oxide.

Preparation of Chromium. Perform the experiment in the presence of your instructor, in a fume cupboard Wear eye protection or a mask ) Roast chromium(III) oxide in an iron crucible. Triturate potassium dichromate crystals in a mortar, melt the powder in a porcelain crucible with the flame of a gas burner, pour the substance onto a glazed tile plate, and after it solidifies again triturate it into a powder. Weigh 12 g of roasted chromium(III) oxide, 12 g of the fused potassium dichromate, and 10 g of an aluminium powder, and thoroughly mix all the substances in a mortar. Spill 10 g of a calcium fluoride powder onto the bottom of a chamotte crucible, and then the prepared mixture. (If there is no chamotte crucible in your laboratory, make a box from asbestos paper in the form of a crucible and fasten it with wire.) Tamp the substance with a pestle and make a hollow in the middle using a test tube (see Fig. 120). 

HETEROCYCLES Copper phcnylace-tylide. Dichlorobis(benzonitrile)palladium. N-Dichloromethylene-N,N-dimcthylammo-nium chloride. Diiminosuccinonitrile. Dimethyl acetylenedicarboxylate. Dipotassium cyanodithioimidocarbonate. Ethoxy-carbonyl isothiocyanate. Ethyldiisopropyl-amine. Ethylene oxide. Hydrogen fluoride. Isocyanomethane-phosphoric acid diethyl ester. Lead tetraacetate. Lithium aluminium hydride. Methylhydrazine. Phosphoryl chloride. Polyphosphate ester. Polyphosphoric acid. Potassium amide. Potassium hydroxide. Tolythiomethyl isocyanide. Tosylmethyl isocyanide, Trichlo-romethylisocyanide dichloride. Trimethyl-silyldiazomethane. 

Metallurgy. — The metals of most of the cerium group elements have been prepared, three general methods having been used t (1) fusion of the anhydrous halides with sodium, potassium, calcium, or aluminium (2) electrolysis of the fused chlorides or of a solution of the oxide in the molten fluoride (3) heating the oxides with magnesium, calcium, or silicon. Reduction with aluminium has also been tried, but it is not satisfactory except possibly for cerium itself. Electrolysis has been the most successful, the other methods usually giving at best an alloy. 

Aluminium potassium sulfate dodecahydrate Aluminium sulfate hydrate <30% aq. sol n Ammonium acetate sat d aq. sol n Ammonium bicarbonate Ammonium carbonate sat d aq sol n Ammonium chloride sat d aq. sol n Ammonium fluoride 30-70% aq. sol n Ammonium hydrogen fluoride Ammonium nitrate Arsenic trichloride Cadmium oxide solid Calcium chloride 30-70% sat d aq. sol n Cobalt sulfate heptahydrate... 

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