Salts, oxygen preparation

Using an oxaziridinium salt derived from dihydroisoquinoline, Lusinchi was able to transfer the oxygen atom to several simple alkenes in good yield (Scheme 5.2) [5,6]. Following this work, the first enantiomerically pure oxaziridinium salt was prepared [7]. Quaternization of chiral oxaziridine (1), derived from (lS,2R)-(+)-norephedrine, produced the oxaziridinium salt (2) (Scheme 5.3). 

The preparation and properties of barium monofluorotrioxiodate, BalOsF, have been described. This sparingly soluble salt was prepared by the reaction of the hydrated hydroxide Ba(0H)2,2H20 with the compound IVIO2F2 in alcohol, and was characterized by X-ray diffraction and i.r. and Raman spectroscopy. The lOsF " ion has three oxygen atoms equidistant from iodine, and, for this reason, easily breaks down in aqueous solution to iodate and fluoride. ... 

Partial demethylation occurred of the spiro cannabinoid compound illustrated by treatment in hexamethylphosphorictriamide with the lithium salt of 2-methylpropane-2-thiol in the same solvent at 70 C during 2 hours to give an 89% yield of (+)-dehydrocannabispiran. The lithium salt was prepared from lithium hydride and the thiol in oxygen-free hexamethylphosphoric triamide by reaction at 50 C during 5 hours (ref.149). 

Nylon salt is prepared as a homogeneous solution of 52 - 53 % concentration. The product is sensitive to oxygen and it is maintained in storage tanks under nitrogen atmosphere. 

Reductive coupling of carbonyl compounds to yield olefins is achieved with titanium (0), which is freshly prepared by reduction of titanium(III) salts with LiAIH4 or with potassium. The removal of two carbonyl oxygen atoms is driven by T1O2 formation- Yields are often excellent even with sensitive or highly hindered olefins. (J.E. McMurry, 1974, 1976A,B). 

Acetoxybenzene is prepared by the reaction of benzene with Pd(OAc)2[325,342-345], This reaction is regarded as a potentially useful method for phenol production from benzene, if carried out with only a catalytic amount of Pd(OAc)2. Extensive studies have been carried out on this reaction in order to achieve a high catalytic turnover. In addition to oxygen and Cu(II) salts, other oxidants, such as HNOi, nitrate[346,347], potassium peroxodisulfate[348], and heteropoly acids[349,3S0], are used. HNO is said to... 

Ra.don Sepa.ra.tion, Owing to its short half-life, radon is normally prepared close to the point of use in laboratory-scale apparatus. Radium salts are dissolved in water and the evolved gases periodically collected. The gas that contains radon, hydrogen, and oxygen is cooled to condense the radon, and the gaseous hydrogen and oxygen are pumped away. 

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