Lithium hydroxide, hydrogenation with

Crystalline, diastereomerieally pure syn-aIdols are also available from chiral A-acylsultams. lhe outcome of the induction can be controlled by appropriate choice of the counterion in the cnolate boron enolates lead, almost exclusively, to one adduct 27 (d.r. >97 3, major adduct/ sum of all other diastereomers) whereas mediation of the addition by lithium or tin leads to the predominant formation of adducts 28. Unfortunately, the latter reaction is plagued by lower induced stereoselectivity (d.r. 66 34 to 88 12, defined as above). In both cases, however, diastereomerieally pure adducts are available by recrystallizing the crude adducts. Esters can be liberated by treatment of the adducts with lithium hydroxide/hydrogen peroxide, whereby the chiral auxiliary reagent can be recovered106. 

The mixtures of alkylation products can be purified by chromatography or, alternatively, by alkaline hydrolysis to afford the dcmethoxycarbonylated heterocycles 5 which can be purified to high diastereomeric purity by recrystallization. The purified major diastereomer can then be hydrolyzed (lithium hydroxide/hydrogen peroxide) followed by protonation to afford the corresponding 2-alkylalkanoic acids 6 with >99% ee4. 

The chiral auxiliary of alkylated A-acylbornane-10,2-sultams can be liberated by the use of hydroperoxide-assisted hydrolysis using lithium hydroxide/hydrogen peroxide9 in tetrahydro-furan/water (see Section 1.1.1.3.3.4.2.1.). This furnishes the chiral acids 2 in very high optical purities, along with the auxiliary which can be recycled. Other mild methods are available20. 

Lithium hydroxide with 12-hydroxy-stearic acid (or hydrogenated castor oil) they form the family of lithium greases very commonly used for general lubrication and bearing lubrication. 

Lithium is used in metallurgical operations for degassing and impurity removal (see Metallurgy). In copper (qv) refining, lithium metal reacts with hydrogen to form lithium hydride which subsequendy reacts, along with further lithium metal, with cuprous oxide to form copper and lithium hydroxide and lithium oxide. The lithium salts are then removed from the surface of the molten copper. 

Lithium Peroxide. Lithium peroxide [12031 -80-0] Li202, is obtained by reaction of hydrogen peroxide and lithium hydroxide in ethanol (72) or water (73). Lithium peroxide, which is very stable as long as it is not exposed to heat or air, reacts rapidly with atmospheric carbon dioxide releasing oxygen. The peroxide decomposes to the oxide at temperatures above 300°C at atmospheric pressure, and below 300°C under vacuum. 

In the reduction of a carbonyl group, there is an initial transfer of a hydride ion by an SN2 mechanism when the complex (1) is formed. Since it has still three more hydrogen atoms, it reacts with three more molecules of ketone to give the alkoxide (2) Hydrolysis of the latter gives secondary alcohol, along with aluminium and lithium hydroxides. 

A mixture of 5.26 g. of rhodium chloride trihydrate, 0.34 g. of palladium chloride, 18 g. of carbon (Darco G-60), and 200 ml. of water is rapidly stirred and heated to 80°. Lithium hydroxide hydrate (2.7 g.) dissolved in 10 ml. of water is added all at once and the heating stopped. The mixture is stirred overnight, filtered, and washed with 100 ml. of 0.5 v/v% aqueous acetic acid. The product is dried under reduced pressure at 65°, giving 20.6-21 g. of the catalyst. One gram of this catalyst consumes 0.0022-0.0028 mole of hydrogen in aqueous suspension. ... 

Lithium reacts with water forming lithium hydroxide with evolution of hydrogen ... 

Addition of aqueous hydrogen peroxide significantly accelerates the substitution reactions with hydroxide. For example, treatment of 2-chloropyrimidine 166 with lithium hydroxide and hydrogen peroxide in water at 50 °C afforded 2-pyrimidinone 167 in 67% yield <2006TL4249>. 

Removal of the auxiliary is straightforward and consists of treatment of the alkylated A -acyl-sultam 5 with an excess of lithium hydroxide/30% hydrogen peroxide in tetrahydrofuran. Other mild cleavage methods are available20. 

The following procedure is based on the reaction of an aqueous solution of cobalt(II) chloride with the equivalent amount of (2-aminoethyl)carbamic acid, followed by oxidation with hydrogen peroxide and the subsequent formation of bis(ethylene-diamine)cobalt(III) ions. The bis(ethylenediamine)cobalt(lII) species are converted to the carbonato complex by reaction with lithium hydroxide and carbon dioxide. During the entire preparation a vigorous stream of carbon dioxide is bubbled through the reaction mixture. This procedure appears to be essential in order to minimize the formation of tris(ethylenediamine)cobalt(III) chloride as a by-product. However, the formation of a negligible amount of the tris salt cannot be avoided. The crude salts have a purity suitable for preparative purposes. The pure salts are obtained by recrystallization from aqueous solution. 

---