Amide salts

Alkan olamines ate used in urethane coatings for glass shatter proofing (68) and have been utilized as amides, salts, or free amines in providing antifrosting, antifogging, and dirt-resistant films on glass and plastics (69—72). 

The following example illustrates in detail the preparation of amino benzoic acids from the hot reaction product obtained by the oxidation of a xylene and containing a mixture of salt, amide salt and diamide of a phthalic acid. 

There is little mention in the literature of the use of amide salts in substitution reactions on chlorophosphazene precursors. The anilide anion was shown to be a powerful nucleophile in substitution reactions on various trimer derivatives, but investigations of such reactions with the high polymer have not been reported.22 Where strong nucleophiles (such as amide salts) with low steric requirements are employed, the usual pentacoordinate transition state (Scheme 1), may be a viable reaction intermediate which can undergo alternative modes of decomposition, perhaps involving chain cleavage and/or cross-linking. 

Amide salts rconh2hci, RCONHRHC1, rconr2hci Yes Generally soluble... 

The ambiguity of infrared criteria for the identification of protonation sites in imidazoles and 2-pyrazolines has been discussed by Elguero et al. (1967a), who have also provided new information on the infrared spectra of the hydrochloride of 3,5,5-trimethyl-2-pyrazoline in chloroform solution. There is a shift of the stretching vibration of the C=N bond from 1624 cm in the base to 1649 cm" in the hydrochloride salt in chloroform, i.e., in the N-1 protonated cation. This is analogous to similar shifts of the carbonyl frequency in some amide salts (see page 338). 

Several lines of kinetic evidence have also to be considered in connection with the site of protonation of amides. Salts of the type [119] (R = Me or Ph) have been prepared by Klages cind Zange... 

Solid cyclic carboxylic anhydrides react with gaseous ammonia to give amide ammonium salts with quantitative yield. This has been observed with the labile Diels-Alder adduct 259 [25] (Scheme 38). Aliphatic amine vapors are equally able to open anhydride rings to form the amide salts from where the free amide acids can be obtained in 100% yield. The reaction of 261 with ethylamine to give 262 is an example of a large-scale preparative application [11-12]. Conversely, solid pyromellitic bis-anhydride (263) and methylamine vapor react exother-mally (rise to 95 °C) and quantitatively to yield the tetraamide 264. Interest-... 

A very large number of mixed metal aluminium amides has been reported. The majority are lithium-aluminium amide salts that exhibit a variety of different structures. Only a small number of ese compounds are discussed here.39,52,57,72,118-138 simplest is LiAl-(NH2)4 produced from the reaction of lithium and aluminium in liquid ammonia at 80 to 100 °C. The atomic arrangement of LiAl(NH2)4 has been studied by IR-spectroscopy and single crystal X-ray crystallography and was found to be a new variant of the GaPS4-type structure. 

In going to polyaza derivatives, the tendency to form adducts decidedly increases. Very reactive compounds, such as 1,2,4-triazines and pteridines, undergo covalent addition in liquid ammonia alone, i.e., without any added amide salts, presumably by a two-stage process via anionic ff-adduct formation. 

In an attempt to achieve an enantioselective Eschenmoser-Claisen rearrangement with amide salts 6, (2R,5R)-l-(fluoroacetyl)-2,5-dimethylpyrrolidine was methylated to give chiral 6d. 5 Reaction of 6d with the lithium salt of (fj-crotyl alcohol gives amide 7d as a mixture of diastereomers, in which the. vj rt-isomers predominate. 

The motivation of this chapter was to show that despite the enormous prospects of ionic liquids in electrodeposition some troublesome aspects have to be expected. Apart from the purity and price of ionic liquids the optimum temperature for any process has to be found. Furthermore, suitable additives for electrodeposition will have to be developed and cation/anion effects that can strongly alter the morphology of deposits have to be expected. Finally, the electrochemical window alone is not the only factor that needs to be considered for the deposition of reactive metals. Suitable precursors will have to be tailor-made and it is our personal opinion that the electrodeposition of metals like Mg, Ti, Ta and Mo may not be possible from metal halides but rather metal bis(trifluoromethylsulfonyl)amide salts and other ones may be more suitable. 

A few years later Arnold and co-workers also reported the synthesis of lithium complexes of the neutral and anionic salts of a tridentate amino bis-carbene ligand (Scheme 2).13 Treatment of the cationic amino bis-imida-zolium salt with three equivalents of //-butyl lithium affords the lithium amino bis-carbene chloride complex (5). Deprotonation with four equivalents of n-butyl lithium affords the lithium amide salt (6). Although the complexes were not characterised in the solid state, characteristic shifts in the multinuclear NMR spectra and elemental analysis are consistent with the lithium complexes being formed. NMR spectra of 5 suggest formation of a cluster of lithium chloride ions with lithium-NHC bonds (13C NMR NCN 203.9 ppm) and NH-chloride bonding interactions. Following further deprotonation to form 6 the complex also retains lithium chloride and exhibits a similar C2 chemical shift (13C NMR NCN 203.4 ppm). 

Enantioselective Ring Opening of Epoxides. In two steps, (l/ ,25)-N-pyrrolidinylnorephedrine can be converted into the analogous diamine 2. Treatment with butyllithium affords an amide salt that can be used as a chiral base. In a limited study, the opening of achiral epoxides to chiral allylic alcohols proceeds in high yield and with good enantioselectivity (eq 4). ... 

Cesium and Rb hydrides react with anhyd on heating to form metal-amide salts ... 

Pringle J M, Golding J, Baranyai K, et al. The effect of anion fluorina-tion in ionic liquids—physical properties of a range of bis(methanesul-fonyl)amide salts. New J. Chem. 2003. 27, 1504-1510. 

The amido ligand is isoelectronic with the alkyl and alkoxo groups and has the possibility to exhibit N-M ir-interactions in order to stabilize the systems they form. Different synthetic reactions are used to prepare mono-Cp titanium derivatives containing amido ligands. These compounds are normally synthesized by (i) the action of the corresponding amide salt on Cp TiCl3, (ii) displacement of amine from a homoleptic amido titanium compound by a Cp reagent, (iii) dehalosilylation reactions, and (iv) elimination of alkane by reaction of an alkyltitanium compound with amine. 

A -Aminopyridinium salts reacted smoothly with 2-methyl-3-phenylcyclopropenone in di-chloromethane in the presence of triethylamine at 20 C to give the corresponding 2-methyl-4-phenyl-3//-pyrido[l,2-A]pyridazin-3-ones la-f in fairly good yield. 2,3-Dipropylcyclo-propenone reacted with pyridinium amide salts in methanol to give 2,4-dipropyl-3//-py-rido[l, 2-6]pyridazin-3-ones Ig-j under reflux conditions. ... 

The checkers found that the solubility of lithium bis(trimethylsilyl)amide salt in diethyl ether was limited, and a slurry rather than a solution resulted in this step. 

Two research groups studied the syntheses of 36 different macrocycles (Atkins et al., 1978 Rasshofer et al., 1976). The yields averaged about 60% but varied from 7% to 90%. The yields of certain macrocycles prepared by both research groups varied by as much as 50%. These variations can be attributed to different reaction conditions, particularly in the methods used to prepare the amide salts, reaction temperatures, purity of starting materials, and reaction times. Careful drying of the solvent and prevention of atmospheric moisture from contacting the moisture sensitive amide salts generally increases the yields for the cyclization step in these reactions (Bhula et al., 1988). 

To 5 mL of THF or Et,0 under an inert atmosphere is added with magnetic stirring, 0.003 mol of (E)- or (Z) 2-butenol followed by 0.003 mol of mcthyllithium (1.55 M in Et20) at r.t. After the mixture is stirred for 5min, 0.003 mol of the O-alkylated amide salt, prepared by treatment of the neat amide with a stoichiometric amount of methyl triflatc, is added in 4 mL of THF or CH2C12. The mixture is allowed to stir at r.t. for the specified time, diluted with 20 mL of CH2C12, washed with three 20-mL portions of sat. aq Na,COj and one 20-mL portion of brine, then dried over MgSQ4 and concentrated in vacuo. 

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