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Ammonia imides from

The well-established synthesis of cyclic sulfur imides from disulfur dichloride and ammonia in A,A -dimethylformamide requires close attention and gives rise to S7NH, Se(NH)2 isomers, and Ss(NH)3 isomers in approximate yields of... [Pg.203]

The imide from which the salt (LVI) is derived is the oxygen analog of the imide corresponding to the silver salt (XLVII). Its probable mode of formation entails initially the loss of ammonia and HOSN from two molecules of HN (SONH2)2. The resulting trimeric thionyl imide then tends to form its anhydride... [Pg.181]

In this case, NA is first made to react with ammonia to form the acid imide, from which perylenetetracarboxylic-diimide is produced by alkali fusion and oxidation this is followed by hydrolysis with concentrated sulfuric add, to perylenetetracarboxylic add. [Pg.341]

An imido analog of phosphorus oxynitride, phospham, (PN2H)a , is made as the exhaustive self-condensation product of aminophosphazenes, but also may be made directly from elemental phosphorus and ammonia or from phosphorus pen-tasulfide and ammonia. Phospham is probably a thermoset phosphazene imide. It can be amorphous or ciystalhne. It is also an elFective and thermally stable flame retardant, especially for high-temperatin-e-processed polyamides (31). It was available for a short time as a development product from Japan. [Pg.5564]

Thermal decomposition of capsaicin yields capsaicin dimer ( )-JV-vanillyl-di(8-methylnon-6-en)imide (10-35), various amides, acids, hydrocarbons and phenols. The main product is E)-S-methylnon-6-enamide, nonanamide, pentanamide and other amides, ( )-8-methylnon-6-enoic acid, nonanoic acid, ( )-hept -2-ene, vanillin and other substituted phenols (2-methoxy-4-methylphenol and 2-methoxyphenol), which are produced by decomposition of vanillin. Roasting of peppers in oil may produce fatty acid amides. For example, reaction with oleic acid yields (Z)-N-vanillyloctadec-9-enamide reaction of oleic acid with ammonia, originating from capsaicin, gives rise to (Z)-octadec-9-enamide (oleamide). [Pg.775]

Give off ammonia freely when treated with aqueous NaOH solution in the cold (distinction from amides, imides and nitriles). [Pg.359]

Lithium Amide. Lithium amide [7782-89-0], LiNH2, is produced from the reaction of anhydrous ammonia and lithium hydride. The compound can also be prepared by the removal of ammonia from solutions of lithium metal in the presence of catalysts (54). Lithium amide starts to decompose at 320°C and melts at 375°C. Decomposition of the amide above 400°C results first in lithium imide, Li2NH, and eventually in lithium nitride, Li N. Lithium amide is used in the production of antioxidants (qv) and antihistamines (see HiSTAMlNE AND HISTAMINE ANTAGONISTS). [Pg.225]

To minimize the formation of fuhninating silver, these complexes should not be prepared from strongly basic suspensions of silver oxide. Highly explosive fuhninating silver, beheved to consist of either silver nitride or silver imide, may detonate spontaneously when silver oxide is heated with ammonia or when alkaline solutions of a silver—amine complex are stored. Addition of appropriate amounts of HCl to a solution of fuhninating silver renders it harmless. Stable silver complexes are also formed from many ahphatic and aromatic amines, eg, ethylamine, aniline, and pyridine. [Pg.90]

Guareschi imides are useful synthetic intermediates. They are formed from a ketone reacting with two equivalents of the cyanoacetic esters and ammonia. This transformation is illustrated in the formation of 4,4-dimethylcyclopentenone 30.The synthesis was initiated with the Guareschi reaction of 3-pentanone 27 with 28 to generate imide 29. This product was hydrolyzed to the diacid and esterified. Cyclization of the diester via acyloin condensation followed by hydrolysis and dehydration afforded the desired target 30. [Pg.308]

As in 10-55 hydrazides and hydroxamic acids can be prepared from carboxylic esters, with hydrazine and hydroxylamine, respectively. Both hydrazine and hydroxylamine react more rapidly than ammonia or primary amines (the alpha effect, p. 445). Imidates, RC(=NH)OR, give amidines, RC(=NH)NH2. Lactones, when treated with ammonia or primary amines, give lactams. Lactams are also produced from y- and 5-amino esters in an internal example of this reaction. [Pg.510]

Follow-up investigations of the earlier spectroscopic studies6 were designed to simulate a catalytic reaction, albeit at low pressures, with both chemical and structural information available from XPS and STM, respectively. With a 30 1 ammonia-to-oxygen ratio imide strings were formed11 at 290 K running in the... [Pg.81]

Figure 5.4 Coadsorption of a 30 1 ammonia-oxygen mixture at a Cu(110) surface at 290 K with the formation of well ordered c(2 x 4) imide chains running in the < 110 > direction. The separation between the rows is 7.2 A and within the rows 5.1 A, the NH species occupying the bridge sites. (Reproduced from Ref. 11,39). Figure 5.4 Coadsorption of a 30 1 ammonia-oxygen mixture at a Cu(110) surface at 290 K with the formation of well ordered c(2 x 4) imide chains running in the < 110 > direction. The separation between the rows is 7.2 A and within the rows 5.1 A, the NH species occupying the bridge sites. (Reproduced from Ref. 11,39).
Ene lactams can be obtained directly from quaternary phthalideisoquino-linium salts by treating them with concentrated ammonium hydroxide. In this way fumaramine (111) was synthesized from bicuculline (88) methiodide (121,124), fumaridine (113) from methiodides of both diastereomeric / - (91) and a-hydrastines (92) (5,124-126), and narceine imide (116) from narcotine (94) methiodide (122,127,128). In the case of the hydrastines (91 and 92) the Hofmann degradation of their methiodides in ammonia was not stereospecific but yielded the thermodynamically more stable Z isomer (113) (5). It seems, however, that from narcotine (94) a mixture of the Z and E forms was produced rather than a single isomer (123,127). [Pg.277]

The formation of imides could be excluded since ammonia could be expelled with magnesium hydroxide from the samples (outgassed at 100°). [Pg.199]

Protected primary allylic amines were generated from allylic carbonates and ammonia equivalents. Iridium-catalyzed allylic substitution has now been reported with sulfonamides [90, 91], imides [89, 91-93], and trifluoroacetamide [89] to form branched, protected, primary allylic amines (Table 5). When tested, yields and selectivities were highest from reactions catalyzed by complexes derived from L2. Reactions of potassium trifluoroacetamide and lithium di-tert-butyhminodi-carboxylate were conducted with catalysts derived from the simplified ligand L7. Reactions of nosylamide and trifluoroacetamide form singly-protected amine products. The other ammonia equivalents lead to the formation of doubly protected allylic amine products, but one protecting group can be removed selectively, except when the product is derived from phthalimide. [Pg.192]

The cyclic sulfur imides S NH and 1,3-, 1,4-, and l,5-S(j(NH)2 are obtained by acid hydrolysis of the deep blue intermediate formed from the reaction of SjClj with ammonia in polar solvents, e.g. DMF or by the reaction of sodium azide with elemental sulfur in HMPA The blue chromophore formed in both these reactions is S4N and it has therefore been suggested that this anion is involved in equilibria with cyclic sulfur-nitrogen anions which are the precursors of the imides... [Pg.132]

Piroxicam Piroxicam, 1,1 -dioxid-4-hydroxy-2-methyl-iV-2-pyradyl-2//-1,2-benzothiazine-3-carboxamide (3.2.78), is synthesized from saccharin (3.2.70). Two methods for saccharin synthesis are described. It usually comes from toluene, which is sulfonated by chlorosulfonic acid, forming isomeric 4- and 2-toluenesulfonyl chlorides. The isomeric products are separated by freezing (chilling). The liquid part, 2-toluenesulfonyl chloride (3.2.68) is separated from the crystallized 4-toluenesulfochloride and reacted with ammonia, giving 2-toluenesul-fonylamide (3.2.69). Oxidation of the product with sodium permanganate or chromium (VI) oxide in sulfuric acid gives saccharin—o-sulfobenzoic acid imide (3.2.70) [123-126]. [Pg.51]

Reactions involving the [4 + 1 + 1] principle, an example of which is shown in equation (136), are rather uncommon and of strictly limited utility [3 + 2 + 1] and [2 + 2 + 2] processes, on th,e other hand, are well known. Representative [3 + 2+1] three-bond formation processes are given in equations (137)—(141), from which it can be seen that the common situation is where ammonia, a substituted amine or formamide constitutes the one-atom fragment. Many [2 + 2 + 2] atom fragment syntheses are known and some are familiar reactions. Thus, the cobalt(I)-catalyzed condensation of nitriles and isocyanates with alkynes gives pyridines and 2-pyridones, often in excellent yield (e.g. equation 142), while the cyclotrimerizations of nitriles, imidates, isocyanates, etc., are well established procedures for the synthesis of 1,3,5-triazine derivatives (e.g. equation 143). Further representative examples are given in equations (144)-(147), and the reader is referred to the monograph chapters for full discussion of these and other [2 + 2 + 2] processes. Examination of the... [Pg.86]

The first report of the preparation of the dialkyl succinimide (29-3) dates back to early in the twentieth cenmry. It is consequently surprising to note that it was introduced as an anticonvulsant, under the name ethosuximide, well after its more recently synthesized congeners. The synthetic route starting from methyl ethyl ketone generally follows that above with the exception of the use of ammonia in the last step. The compound thus differs as well by possessing a somewhat acidic imide proton [30]. [Pg.257]

Metallic amides and imides can be pptd from liq ammonia solns of certain metallic salts by the action of potassium amide, KNH2 Some amides and imides are explosive, eg, silver amide and lead imide (Compare with Nitrides) (See also Polyamides)... [Pg.168]

Trimerization of imidates is a valuable route to 1,3,5-triazines. Imidates can be considered as activated nitriles and cyclotrimerize more readily. Most symmetrical 2,4,6-trialkyl-1,3,5-triazines are easily formed, although large alkyl substituents may give rise to steric hindrance (61JOC2778). Symmetrical isocyanurates (525) are readily available from isocyanates, RNCO catalysts include tertiary amines, phosphines and sodium methoxide. Aldehydes RCHO and ammonia give hexahydro-1,3,5-triazines (526), known as aldehyde ammonias (73JOC3288). [Pg.600]

In the first stage of the reaction an alkoxyl anion and the nitrohydrazine cation are formed which afterwards react together to give the corresponding alcohol and nitrohydrazine. Nitrohydrazine reacts with excess hydrazine to produce tetrazene, nitrous acid and di-imid. Then the tetrazene decomposes to form ammonia and nitrogen from di-imid on the other hand tetrazene, hydrazine and nitrogen are formed. Hydrazoic acid and ammonia are then formed as decomposition products of tetrazene. [Pg.12]


See other pages where Ammonia imides from is mentioned: [Pg.261]    [Pg.213]    [Pg.181]    [Pg.283]    [Pg.35]    [Pg.104]    [Pg.112]    [Pg.8]    [Pg.403]    [Pg.182]    [Pg.80]    [Pg.490]    [Pg.276]    [Pg.99]    [Pg.192]    [Pg.169]    [Pg.130]    [Pg.614]    [Pg.557]    [Pg.266]    [Pg.374]    [Pg.405]    [Pg.23]    [Pg.240]    [Pg.237]    [Pg.88]   
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