Amides solubility

Sparingly soluble amides crystallise out from the reaction mixture upon standing, for example ... 

Thickeners. These are used to kicrease viscosity of shampoos to achieve certain consistency characteristics ki the product, from a thickened Hquid to gels and pastes. Among the most important materials used for this purpose are the alkanolamides. The chain length of the amide alkyl group and its solubiHty ki the shampoo system are important aspects to be considered ki thek use for effects on viscosity. In general, as the chain length increases the viscosity response improves. The viscosity increase also is related to the water solubiHty of the amide the more water-soluble forms provide a lower viscosity response than the less soluble amides. 

Rearrangements Emmons found the reagent suitable for Beckmann rearrangements giving water soluble amides. Thus methyl cyclopropyl ketoxime in the medium of 1, 2-dimethoyethane was treated under reflux with stirring with trifluoroacetic anhydride in 1 hr. and refluxed for 1 hr. more. The cyclopropylamine was obtained. 

In an aqueous solution, water-soluble amides have been nitrosated in the presence of sodium nitrite on acidification with mineral acids. This procedure appears to be restricted to amides which are water-soluble. Evidently, only amides derived from primary carbinamines may be prepared by this method. The reaction is somewhat slow, requires a large excess of sodium nitrite, evolves... 

Sulfonylation of amines can be a useful way of differentiating (chemically) between primary, secondary, and tertiary amines by what is known as the Hinsberg test. Primary and secondary amines both react with a sulfonyl chloride, but only the sulfonamide from the primary amines has an N—H hydrogen. The sulfonyl group makes this hydrogen relatively acidic and the sulfonamide therefore dissolves readily in sodium hydroxide solutions. The secondary amine does not give a base-soluble amide, whereas the tertiary amine gives no sulfonamide ... 

The acyl chloride (the crude material prepared by the thionyl chloride method is quite satisfactory) is added dropwise to well-stirred concentrated aqueous ammonia cooled in a freezing mixture. The amides of the higher carboxylic acids crystallise out on standing and need only to be filtered and recrystallised. Water-soluble amides are isolated by extraction with hot ethyl acetate following removal of water on a rotary evaporator. 

The reaction usually proceeds readily in the cold, particularly when the methyl esters of the lower molecular weight carboxylic acids are involved. Sparingly soluble amides crystallise out from the reaction mixture upon standing, as in the case of succinamide (Expt 5.155). 

Metathesis reactions between Group 2 metal alkoxides and lithium amides in hexane yield the metal amide and lithium alkoxide according to Eq. (7).60 The lithium alkoxide is insoluble in hexane and is easily separated from the hexane-soluble amide. 

Treatment of S4(NH)4 with ozone converts it into a linear polymer (—SO—NH—) the brown, insoluble material has also been made by treating thionyl chloride with ammonia in the vapour phase. Thionyl fluoride, however, reacts with ammonia to give a volatile ether-soluble amide as the initial product ... 

Rearrangements. Emmons found the reagent useful for Beckmann rearrangements giving water-soluble amides. Thus a solution of methyl cyclopropyl ketoxime NOH... 

In liquid ammonia soluble amides act as bases, which may formally be compared with hydroxides in water. Likewise imides such as Pb(NH) are formally analogous to oxides in water which by addition of the solvent may display basic properties. In liquid ammonia a third type of potential base is known, namely nitrides. 

MACKAMIDE NOA is an oil soluble amide which provides excellent water in oil emulsions. It is also water dispersible and when blended with anionic surfactants provides excellent viscosity building properties at very low concentrations. 

MACKAMIDE S is an oil soluble soya dlethanolmide. As such, it forms water in oil emulsions and is a good corrosion inhibitor. MACKAMIDE S may be used in aqueous systems where small amounts in conjunction with water soluble amides will give increased viscosity response. MACKAMIDE S will also contribute to foam stability and detergency as well as lending conditioning and lubricating properties to skin and hair. 

Low molecular weight higher functional substituted macrocyclic metal complexes (M = Co, Ni, Cu, Zn) were converted with other bifunctional compounds to polymers. By the reaction of tetraaminophthalocyanine in the presence of another diamine with benzenetetracarboxylic acid dianhydride, at first in dimethylsulfoxide (DMSO) soluble amide-carbocylic acid copolymers were obtained and after film casting and... 

Grafting anionically prepared polybutadiene with MA, in a 4 1 weight ratio, at 200°Cgave copolymer with 16% grafted anhydride. Ammonolysis gave a water-soluble amide-ammonium salt useful in waterborne coatings. 

Amide formation, has already been outlined in connection with the laboratory work, page 138. Low molecular weight acids yield water-soluble amides, and for this reason it is advisable to prepare instead the less soluble anilides or p-toluidides (page 144). Mulliken, I, 80-81, has outlined convenient directions for the identification of acetic, propionic, but Tic, and isobuttmic acids in the form of the corresponding p-toluidides. These acids are usually met in aqueous solution and it is not feasible to convert them into acyl halides instead, the aqueous solution is neutralized with NaOH, evaporated, and the resultant sodium salt utilized in the test. 

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