Alkali metal amides sodium

Of the alkali metal amides sodium amide is more frequently used than any other amide. In the past it was used in mineral oil at elevated temperatures (equation 43) ... 

Salts of very powerful oxidizing acids (eg chromic or permanganic) are unknown, and are unlikely to exist. Hydrazonium iodate may exist in solution at low temp (Ref 27a). Alkali metals, amides and hydrides react with hydrazine to give the corresponding alkali hydrazide. Sodium hydrazide explodes violently in the presence of 02 or when heated above 100°C—a typical behavior of the alkali hydrazides. For other reactions, see Ref 24 Explosive and Combustion Properties... 

Ring Additions Catalyzed by Alkali Metals. The addition of tributyl tin chloride and olefins such as styrene, isoprene, or butadiene to sulfolane is catalyzed by alkali metals, including sodium and lithium, and by sodium amide (10—13). The addition of tributyltin chloride to sulfolane in the... 

The intervening years have seen huge growth in the number of well-characterized compounds, the vast majority of which are lithium, sodium or potassium salts. Their strucuiral chemistry has proven to be especially rich and the number of structures of alkali metal amides currently available exceeds 200. These involve a wide selection of structural motifs that were mostly unknown in 1980. 

Although the first bis(iminophosphorano)methanides were reported by Elsevier,15 the first structurally characterised examples were reported by Cavell.16 Solvent-free 1 and 2 were prepared from the reaction between the parent methane and lithium or sodium bis(trimethylsilyl)amides in aromatic solvents. By avoiding Lewis base solvents such as ethers, dimeric complexes were isolated. Treatment with excess quantities of alkali metal amide did not effect a second deprotonation, even under reflux conditions over days, which was attributed to the less basic nature of amides compared to alkyls (see section 3.2 below). In addition to the expected methanide-alkali metal bonds, methine C H — Li interactions were observed in 1 in the solid state but the analogous C-H — Na interactions appeared to be weak in 2. 

Since most of the synthetically useful enolate anions described in the previous section are prepared by the reactions of enolizable substrates with alkali metal amide bases, it is appropriate to note a few structures of these amide bases. The common bases in synthetic organic chemistry include LDA and LHMDS. The structures of both of these bases are known as the THF solvates.Both of these compounds form bis-solvated dimers corresponding to structure (201). The diethyl ether solvate of LHMDS also forms a bis-solvated dimer (202).Sodium hexamethyldisilazide crystallizes as an unaggregated monomer from benzene solution.Two different cryst line forms of KHMDS are known as the polymeric dioxane solvate (203), ° and the unsolvated dimer (204). ... 

The alkali metal amides are stronger bases than the alkoxides. Therefore, in many reactions milder conditions can be applied sodium amide in liquid NH3 is most widely used. In contrast to the oxygen... 

Other pyridine derivatives have been aminated with alkali metal amides. Treatment of 2,3 -bipyridine (116) with sodium amide afforded the isomers shown in Scheme 46 (77MI1). In a similar fashion, 2,2 -bipyridine gave 6,6 -diamino-2,2 -bipyridine, 3,3 -bipyridine yielded 6-amino-3,3 -bipyridine, and 4,4 -bipyridine afforded 2,2 -diamino-4,4 -bipyridine upon treatment with sodium amide (78RCR1042). The amination of 2-chloro-5-nitropyridine gave the Chichibabin products 2-amino-6-chloro-3-nitropyridine and 4-amino-2-chloro-5-nitropyridine in low yields (<3% of each) on treatment with potassium amide in liquid ammonia. The main product was 2-amino-5-nitropyridine, obtained primarily by the S fANRORC) mechanism (85JOC484). 

Alkali metals react with ammonia to yield alkali metal amides such as sodium amide, a reactive substance used as a reagent. They decompose in water or acid to evolve ammonia and produce very caustic alkali solutions. 

Synthetically important alkali—metal amides Lithium, sodium, and potassium hexamethyldisilazides, diisopropylamides, and tetramethylpiper-idides 13AG(E)11470. 

One of the first solvent-free alkali metal amides to be investigated was potassium diethylamide, 149 [122]. In the solid state, rings of (KNEt2)2 units form a complicated network. An interesting ladder strueture containing amide bridges and n-coordination was found for sodium 2,3,4,5-tetramethylpyrrolide, 150 [123]. 

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