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Succinimide reaction with

Reactions with Nitrogen Compounds. Succinimide [123-56-8] mp 126°C, can be prepared by reaction of aqueous solutions of the acid with ammonia (105) or urea (106) (eq. 7). The solution is heated until water and ammonia are no longer evolved and the molten cmde succinimide is purified by fractionation. Alternatively, the cmde product can be recrystaUized from water (105). [Pg.536]

In a more recent study on 1,3-dipolar cycloaddition reactions the use of succi-nimide instead of the oxazolidinone auxiliary was introduced (Scheme 6.19) [58]. The succinimide derivatives 24a,b are more reactive towards the 1,3-dipolar cycloaddition reaction with nitrone la and the reaction proceeds in the absence of a catalyst. In the presence of TiCl2-TADDOLate catalyst 23a (5 mol%) the reaction of la with 24a proceeds at -20 to -10 °C, and after conversion of the unstable succinimide adduct into the amide derivative, the corresponding product 25 was obtained in an endojexo ratio of <5 >95. Additionally, the enantioselectivity of the reaction of 72% ee is also an improvement compared to the analogous reaction of the oxazolidinone derivative 19. Similar improvements were obtained in reactions of other related nitrones with 24a and b. [Pg.227]

The cyclized analog of meralluride is prepared by a similar synthesis. Thus, condensation of camphoric acid (42) (obtained by oxidation of camphor) with ammonia gives the bicyclic succinimide (44). Reaction with allyl isocyanate followed by ring opening and then reaction with mercuric acetate affords the mercury derivative (45) as the acetate rather than the hydroxide as above. Reaction with sodium chloride converts that acetate to the halide (46). Displacement on mercury with the disodium salt of thioglycollic acid affords the diuretic mercaptomerine (47). ... [Pg.224]

Simple alkyl halides can be prepared by radical halogenation of alkanes, but mixtures of products usually result. The reactivity order of alkanes toward halogenation is identical to the stability order of radicals R3C- > R2CH- > RCH2-. Alkyl halides can also be prepared from alkenes by reaction with /V-bromo-succinimide (NBS) to give the product of allylic bromination. The NBS bromi-nation of alkenes takes place through an intermediate allylic radical, which is stabilized by resonance. [Pg.352]

Another reagent that is extremely useful synthetically is N-bromo-succinimide (NBS, 85), which is highly selective in attacking only weak C—H bonds, i.e. at allylic, benzylic, etc., positions. It requires the presence of radical initiators, and has been shown to effect bromination through providing a constant, but very low, ambient concentration of Br2—this is maintained through reaction of the HBr produced in the reaction with NBS (c, below). TTiere is usually a trace of Br2 or HBr in the NBS that can react with the initiator to generate the initial Br to start reaction (a, below) ... [Pg.327]

Kojic acid was brominated at position 6 with bromine water4 the 2-(chloromethyl) derivative of kojic acid was brominated with N-bromo-succinimide,87 and chlorinated with sulfuryl chloride and aluminum chloride,88 in both cases probably at C6. The C-benzoylation89 and C-acetylation90 of kojic acid, likewise at C6, was accomplished by Woods using a modification of the Friedel-Crafts reaction. The 2-carboxyethyl side chain was introduced at C6 in a reaction with 2-bromopropionic acid.91... [Pg.171]

Similarly, reaction with succinimide yields mercury succinimide [584-43-0]. [Pg.578]

A-Acyl peptides 277 containing an a,a-di(isopropylthio)glycine residue have also been described. These compounds were prepared as shown in Scheme 7.89. Thus, a 4,4-di(isopropylthio)-2-substituted-5(4//)-oxazolone 276 was prepared from a 2-substituted-5(4//)-oxazolone 275 by reaction with A-(isopropylsulfenyl)-succinimide. The starting 2-substituted-5(4//)-oxazolone was prepared by cychza-tion of an A-acylglycine. °... [Pg.190]

Another method for the preparation of bicyclic lactams consists of formation of a succinimide 5, followed by reaction with a hydride or an organometallic reagent to give a carbonyl equivalent that is readily cyclized upon workup10 15. [Pg.870]

Miscellaneous Compounds. A saturated spirocychc pyrrohdine serves as the nucleus for a diamine that has been described as a hypohpemic agent. Treatment of the carbanion of the substituted cylcohexane carboxyhc ester (20-1) with methyl bromoacetate leads to the alkylation and formation of the diester (20-2). Saponification of the ester groups followed by reaction with acetic anhydride leads to ring closure of the succinic anhydride (20-3). Condensation with ammonia leads to the succinimide (20-4). The side chain is then added by alkylation of the anion on nitrogen with l-bromo-4-dimethylaminobutane (20-5). Reaction of this last intermediate with lithium aluminum hydride leads to the reduction of the carbonyl groups to methylene. This affords the pyrrolidine (20-6) atiprimod [22]. [Pg.251]

Boron trifluoride and boron trifluoride-diethyl ether complex can be used as a source of fluoride ions in the presence of hypobromites and hypochlorites, e.g. methyl hypobromitc, tert-butyl hypobromite, methyl hypochlorite in carbon tetrachloride at 25 C. The addition of bromine monofluoride" and chlorine monofluoride" to various alkenes is accompanied by the formation of the corresponding alkoxybromides and alkoxychlorides which hinder the isolation of the halofluorinated products.57 jV-Bromo- and A -chloro-substiluted alkyl- and arylamines. -amides, and -imides, A -chloro-A,-methylamine, A -bromo-A -methylamine, A -chloro-A, /V-dimethylamine, A-bromo-A.A-dimethylamine, ACV-dichloro-A -methylamine, V,fV-dibromo-,V-mcthylaminc, A -bromosuccinimide, -V-chlorosuccinimide, Af-bromoacct-amide, A.A -dichlorourethane, can be used in the reaction instead of the hypohalites. The reactions with various alkenes conducted in dichloromethane at room temperature in the presence of boron trifluoride-diethyl ether complex produce bromofluoro and chlorofluoro addition products in 40-80 % yield. However, the reactions are complicated by the addition of A -halo-succinimides and Af.A-dichlorourcthane to the C = C bonds.58... [Pg.244]

The most efficient photosubstitution reaction, with many applications in synthesis, is the photobromination method developed by FERRIER s group [24]. The substitution of H-5 is regioselective and stereoselective for pentopyranosides [25], hexo-pyranosides [26], 1-6 anhydrosugars [27], uronic acids [24, 28] heterocyclic derivatives from deoxyinosones [29], nucleosides [30, 31], etc.. . using bromine or N-bromo-succinimide in carbon tetracloride under irradiation. [Pg.48]

The synthesis of methyl (methyl 3-deoxy-D-ara/uno-heptulopyranosid)-onate (124) is shown in Scheme 11. 2-Deoxy-D-ura/uno-hexose (125) is converted into the propylene dithioacetal (126) which reacts with acetone to give 2-deoxy-3,4 5,6-di-<9-isopropylidene-D-c -c//vHohexose propylene dithioacetal (127). Treatment of 127 with n-butyllithium is followed by reaction with methylchloroformiate and removal of the dithioacetal with A-bromo-succinimide gives 120. Removal of the isopropylidene groups afforded 124.312... [Pg.240]

Figure 5 Covalent coupling of cyclic peptide moieties to human serum albumin (HSA). The depicted cyclic peptide, C SRNLIDC, in which C denotes the cyclizing cysteine residues, mimics the receptor binding site of PDGF-BB. First, a sulfhydryl group is introduced to the cyclic peptide by a reaction with succinimide-acetyl thioacetate (SATA). The primary amino groups of lysine in HSA are derivitized with maleimide-hexoyl-At-hydroxysuccinimide ester (MHS). Subsequently, the cyclic peptide is coupled to HSA. In this latter reaction, hydroxyl amine is used to remove the protecting acetate group from the sulfhydryl group of the cyclic peptide. Figure 5 Covalent coupling of cyclic peptide moieties to human serum albumin (HSA). The depicted cyclic peptide, C SRNLIDC, in which C denotes the cyclizing cysteine residues, mimics the receptor binding site of PDGF-BB. First, a sulfhydryl group is introduced to the cyclic peptide by a reaction with succinimide-acetyl thioacetate (SATA). The primary amino groups of lysine in HSA are derivitized with maleimide-hexoyl-At-hydroxysuccinimide ester (MHS). Subsequently, the cyclic peptide is coupled to HSA. In this latter reaction, hydroxyl amine is used to remove the protecting acetate group from the sulfhydryl group of the cyclic peptide.
In engine oil acid-base reactions with proton transfer, logKBH+A. > 103, occurs in systems, e.g., sulfuric acid + carbonate or sulfuric acid + phenate however, the majority of reactions belong to the group without proton transfer, logKB HA < 103, e.g., carboxylic acid + succinimide or phenol + succinimide. [Pg.115]

Undecylenic acid has also been shown to react with the surface preferentially at the alkene end, leaving the terminal carboxylic acid group free for further reaction [53], This result was somewhat unexpected as the Si-H sites are considered to be somewhat acidic and the oxophilic nature of silicon should thermodynamically favor reaction with the hydroxyl group of the acid. The preferential reactivity with the alkenyl end is consistent with a free radical, rather than a nucleophilic mechanism. The acid function can be activated with N-hydroxy succinimide (NHS) to facilitate coupling with amine tagged molecules. Schematically,... [Pg.301]

Alicyclic Imides. In contrast to their aliphatic ketone counterparts, A-alkyl alicyclic imides (succinimides and glutarimides derivatives) could obtain a certain importance in the Norrish-Yang reaction. With a n,n absorption band between 230 and 270 nm, the 254 nm emission of a low-pressure mercury lamp is convenient for exciting... [Pg.49]


See other pages where Succinimide reaction with is mentioned: [Pg.141]    [Pg.59]    [Pg.76]    [Pg.246]    [Pg.897]    [Pg.22]    [Pg.221]    [Pg.1108]    [Pg.463]    [Pg.561]    [Pg.644]    [Pg.318]    [Pg.186]    [Pg.603]    [Pg.320]    [Pg.89]    [Pg.30]    [Pg.29]    [Pg.283]   


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