Sodium amide£ handling

Caution. Sodium amide is a very reactive substance it combines with oxygen and reacts explosively with water. The submitters recommended keeping the amide in sealed glass containers in an atmosphere of ammonia. The checkers preferred the use of petroleum fractions for greater convenience in handling they have kept specimens under this solvent for three years without appreciable loss in activity. 

Sodium azide and other heavy metal azides are too dangerous to be handled by this procedure and should be treated as explosives. Sodium amide and potassium amide can be destroyed by standard procedures. Many other compounds in which nitrogen is linked to a metal should be disposed of as potential explosives. 

Caution. Extreme care should be taken in handling sodium amide, especially during the grinding of the material. Rubber gloves and a face mask should be worn, and the amide should be ground in small portions. Sodium amide, especially corroded pieces, has been reported to detonate without apparent cau.se. Contact with water should be carefully avoided. 

L1AIH4 is often the best reagent, and gives alcohols by the mechanism we discussed in Chapter 12. As a milder alternative (L1AIH4 has caused countless fires through careless handling), lithium borohydride in alcoholic solution will reduce esters—in fact, it has useful selectivity for esters over acids or amides that LiAlH4 does not have. Sodium borohydride reduces most esters only rather slowly. 

Conversion of phosphonium salts to salt-free solutions of ylides can also be effected with sodium bis(trimethylsilyl)amide. As it is soluble in many solvents, and easy to handle and to weigh out, sodium bis(trimethylsilyl)amide is preferred to sodamide in liquid ammonia in many cases (equation 11). The corresponding potassium and lithium compounds can also be used. ... 

The amide of fluoroacetate, fluoroacetamide (4) is a rodenticide with similar properties (Chapman and Phillips, 1955). Its toxicity to mammals is somewhat lower than that of sodium fluoroacetate, and it is probably safer to handle. 

As can be seen from Table 1 sodium tert-butoxide gives similar results compared to lithium amides as base (entries 1 and 2). Both are superior to lithium tcrt-butoxide (entries 3 and 4). Since NaOtBu is easier to handle it seems to be the base of choice for this reaction. With tri-o-tolylphosphine as ligand the procedure is limited to secondary amines. Nevertheless, some application of this new method - mainly from industrial... 

The mechanism of the Chichibabin reaction is still not clear, mainly due to the difficulties to handle with highly reactive alkali amides and also to study reaction kinetics under such specific conditions. Nevertheless, several remarkable observations shed some light on the mechanistic features of the process. Indeed, it has been found that heterocycles with values of 5-6 are aminated easily, while aromatic substrates with a lower basicity exhibit a low reactivity or undergo decomposition. Dependence of the reaction on basic character of starting azaaromatics suggests that the formation of an adsorbtion complex of the type 1 (Scheme 3) with a weak coordination bond between the ring nitrogen atom and sodium ion may be... 

The ease of handling and availability of bleach (chlorox sodium hypochlorite) has led to several applications of this venerable variation of the HR. An early example of the use of sodium hypochlorite is the conversion of cyanoamide 77 to a mixture of methyldioxycopazoline (78) and 2-methyl-4,5-diaminop3Tidine In the stereospecific conversion of amide 80 to... 

Stronger bases, such as amide anion, methylsulfinylcarbanion (the conjugate base of dimethyl sulfoxide), and triphenylmethyl anion, are capable of effecting rapid and essentially complete conversion of a ketone to its enolate. Lithium diisopropylamide, generated by addition of Ai-butyllithium to diisopropylamine, is widely used for this purpose. It is a very strong base, yet is sufficiently bulky so as to be relatively nonnucleophilic—a feature that is important in reducing a number of side reactions. The lithium and sodium salts of hexamethyldisilazane [(CH3)3Si]2NH are easily prepared and handled compounds with properties similar... 

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