Lithium aluminum hydride-Cobalt

Related Reagents. Lithium Aluminum Hydride-(2,2 -Bipy-ridyl)(l,5-cyclooctadiene)nickel Lithium Aluminum Hydride-Bis(cyclopentadienyl)nickel Lithium Aluminum Hydride-Boron Trifluoride Etherate Lithium Aluminum Hydride-Cerium(III) Chloride Lithium Aluminum Hydride-2,2 -Dihydroxy-l, E-binaphthyl Lithium Aluminum Hydride-Chromium(III) Chloride Lithium Aluminum Hydride-Cobalt(II) Chloride Lithium Aluminum Hydride-Copper(I) Iodide Lithium Aluminum Hydride-Diphosphoms Tetraiodide Lithium Aluminum Hydride-Nickel(II) Chloride Lithium Aluminum Hydride-Titanium(IV) Chloride Titanium(III) Chloride-Lithium Aluminum Hydride. 

Common catalyst compositions contain oxides or ionic forms of platinum, nickel, copper, cobalt, or palladium which are often present as mixtures of more than one metal. Metal hydrides, such as lithium aluminum hydride [16853-85-3] or sodium borohydride [16940-66-2] can also be used to reduce aldehydes. Depending on additional functionahties that may be present in the aldehyde molecule, specialized reducing reagents such as trimethoxyalurninum hydride or alkylboranes (less reactive and more selective) may be used. Other less industrially significant reduction procedures such as the Clemmensen reduction or the modified Wolff-Kishner reduction exist as well. 

The azidohydrins obtained by azide ion opening of epoxides, except for those possessing a tertiary hydroxy group, can be readily converted to azido mesylates on treatment with pyridine/methanesulfonyl chloride. Reduction and subsequent aziridine formation results upon reaction with hydrazine/ Raney nickel, lithium aluminum hydride, or sodium borohydride/cobalt(II)... 

The azido mesylate may also be reduced with lithium aluminum hydride in the same manner as previously described for iodo azide reductions. The sodium borohydride/cobalt(II)tris(a,a -dipyridyl)bromide reagent may be used, but it does not seem to offer any advantages over the more facile lithium aluminum hydride or hydrazine/Raney nickel procedures. 

Some bis(salicylaldehydo) complexes of cobalt(II), nickel(II), and cop-per(II), with or without lithium aluminum hydride, are said to catalyze hydrogenation of benzene and alkylbenzenes at 200°C, but the systems appear to be heterogeneous (447). 

Equation 4 indicates a rapid, irreversible formation of hydroxypentacyano-cobaltate(III) and is analogous to the cleavage of hydroperoxides by lithium aluminum hydride (17) involving oxygen-oxygen bond scission. Equation 5... 

REDUCTION, REAGENTS Aluminum amalgam. Borane-Dimethyl sulfide. Borane-Tetrahydrofurane. t-Butylaminoborane. /-Butyl-9-borabicyclo[3.3.1]nonane. Cobalt boride— f-Butylamineborane. Diisobutylaluminum hydride. Diisopropylamine-Borane. Diphenylamine-Borane. Diphenyltin dihydride. NB-Enantrane. NB-Enantride. Erbium chloride. Hydrazine, lodotrimethylsilane. Lithium-Ammonia. Lithium aluminum hydride. Lithium borohydride. Lithium bronze. Lithium n-butylborohydride. Lithium 9,9-di-n-butyl-9-borabicyclo[3.3.11nonate. Lithium diisobutyl-f-butylaluminum hydride. Lithium tris[(3-ethyl-3pentylK>xy)aluminum hydride. Nickel-Graphite. Potassium tri-sec-butylborohydride. Samarium(II) iodide. Sodium-Ammonia. Sodium bis(2-mcthoxyethoxy)aluminum hydride. 

The cobalt dinitrosoalkane complexes are useful precursors of 1,2-diamines by reduction with lithium aluminum hydride a one pot procedure from the alkene yields prevalently the syn (lk) diamines (Table 4). 

When 5,6-anhydro-l,2-0-isopropylidene-a-I>-glucofuianose (67) in ether was allowed to react with carbon monoxide (12 atmospheres, at room temperature) in the presence of sodium cobalt tetracarbonyl for 3 days, the stoichiometric amount of carbon monoxide was absorbed. The mixture was cooled to —5 , and subsequent treatment with methanol and iodine by the procedure of Heck and Breslow resulted in the formation (in 80 % yield) of the methyl uronate (70) and, in a yield of about 10%, the 6-deoxy-hexos-5-ulose (69). Reduction of the methyl uronate (70) and of the dialdose derivative (68) with lithium aluminum hydride yielded identical sugars. 

Lithium aluminum hydride under moderate conditions does not cleave benzyl ethers. Allerton and Fletcher treated 1,4 3,6-dianhydro-2,5-di-0-benzyl-D-mannitol with an excess of lithium aluminum hydride in boiling tetrahydrofuran for six hours, and recovered the starting material in 82 % yield. The stability of the benzyloxy group to this reagent had previously been reported. Some caution should be exercised if vigorous conditions are employed. In the presence of cobaltous chloride, benzyl phenyl ether is hydrogenolyzed to a small extent by lithium aluminum hydride. Zinc dust-acetic acid is reported as not reacting with benzyl ethers. ... 

Recent patent disclosures by the Standard Oil Co. of Indiana indicate that their process for the polymerization of ethylene is also a relatively low-pressure process, and the following process information is based on these disclosures. The polymerization process is a fixed-bed process employing a prereduced catalyst, ethylene pressures of 809-1,000 psi, and temperatures somewhat greater than 200°C. The metal oxides (such as nickel, cobalt, and molybdenum) can be supported on either charcoal or alumina, and materials such as lithium aluminum hydride, boron, alkali metals, and alkaline-earth hydrides may be used as promotors. Variations of this process are reported to produce polyethylene resins with densities from 0.94-0.97. 

Laevulose. See Fructose Lagorex CO 10X. See Cobalt octoate LAH. See Lithium aluminum hydride Lake black extra. See Solvent black 5 Lake bordeaux B. See D C Red No. 34 Lake red 4R. See Pigment red 3 Lake red C. See D C Red No. 8 D C Red No. 9 Lakewax 20. See Montan wax Lakewax 29, Lakewax 37. See Polyethylene, oxidized... 

Retinol (1) was very readily obtained from commercial retinyl acetate (9) by alkali-catalyzed hydrolysis (Isler et al., 1947, 1949 Samecki et al., 1962). Reduction of esters of retinoic acid (3) with lithium aluminum hydride (Matsui et al., 1962b) and with hydrogen and Raney nickel (Organon, 1950) also gave retinol (1), this also being the product obtained when retinaldehyde (2) was reduced by various methods, for example, with sodium borohydride or lithium borohydride (Kaegi et al., 1982), aluminum isopropylate (Shchavlinskii et al., 1979), lithium aluminum hydride (Robeson et al., 1955a Pommer, 1960), or catalytic reduction over platinum(IV) oxide/cobalt(II) acetate tetrahydrate (Steiner, 1974). 

Many methods of reduction from azide to amine are available hydrogen with various metal catalysts, lithium aluminum hydride, or cobalt(II) chloride/sodium borohydride. 

Substances that catch fire spontaneously in air without an ignition source are called pyrophoric. These include several elements— white phosphorus, the alkali metals (group lA), and powdered forms of magnesium, calcium, cobalt, manganese, iron, zirconium, and aluminum. Also included are some organometallic compounds, such as ethyllithium (LiC2H5) and phenyllithium (LiQHj), and some metal carbonyl compounds such as iron pentacarbonyl, Fe(CO)5. Another major class of pyrophoric compounds consists of metal and metalloid hydrides, including lithium hydride, LiH ... 

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