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Amine the reaction

Most of the characteristic reactions of ketones (RR CO) depend upon condensation with substituted amines. The reactions occur between the carbonyl group and the —NHj group of the substituted amine, and hence are also shared by aldehydes RHCO ... [Pg.341]

Ammonia and amines add to acrylates to form P-aminopropionates, which add easily to excess acrylate to give tertiary amines. The reactions are reversible (33). [Pg.151]

For an alcohol, glycol, or glycerol, or for amines, the reaction maybe represented ... [Pg.32]

Diglycolamine Systems. The Fluor Econamine process uses digl> co lamine (DGA) to sweeten natural gas. The active DGA reagent is 2-(2-tunino-ethoxy) ethanol, w hich is a primary amine. The reactions of DG, with acid gases are the same as for MEA. Degradation products from reactions with COS and CS2 can be regenerated in a reclaimer. [Pg.166]

Aminoquinazolines have been the subject of considerable investigation and a large number of derivatives have been prepared as potential antimalarials. The secondary and tertiary amino compounds can be prepared from the corresponding chloroquinazolines and the required primary or secondary amines. The reaction depends on the reactivity of the halogen atom, e.g, the 4-chloro atom reacts more readily than the 2-chloro atom in quinazolines and also on the basic strength of the amine used (see 6a). The reaction is... [Pg.296]

Apart from tertiary amines, the reaction may be catalyzed by phosphines, e.g. tri- -butylphosphine or by diethylaluminium iodide." When a chiral catalyst, such as quinuclidin-3-ol 8 is used in enantiomerically enriched form, an asymmetric Baylis-Hillman reaction is possible. In the reaction of ethyl vinyl ketone with an aromatic aldehyde in the presence of one enantiomer of a chiral 3-(hydroxybenzyl)-pyrrolizidine as base, the coupling product has been obtained in enantiomeric excess of up to 70%, e.g. 11 from 9 - -10 ... [Pg.29]

For aryl amines the reaction mixture should be slightly acidic or neutral, in order to have a high concentration of free amine as well as arenediazonium ions. Aryl ammonium species—ArNH3+—are unreactive. The coupling of the diazonium species with aromatic amines proceeds by an analogous mechanism ... [Pg.84]

Nickel in the presence of ammonia is often used for reduction of nitriles to primary amines. The reaction is done at elevated temperatures and pressures ( 100 C, 1000 psig) unless massive amounts of nickel are used. Cobalt is used similarly but mainly under even more vigorous conditions. Nitriles containing a benzylamine can be reduced over Raney nickel to an amine without hydrogenolysis of the benzyl group (7). A solution of butoxycarbonyl)-3-aminopropyl]-N-<3-cyanopropyl)benzylamine (13.6 g) in 100 ml of ethanol containing 4 g. NaOH was reduced over 3.0 g Raney nickel at 40 psig for 28 h. The yield of A/ -benzyl-Air -(f-butoxycarbonyl)s >ermidine was 95% (7). [Pg.97]

A high yield of diesters can be obtained by controlling the reaction between phosphorus trichloride and alcohol. In the presence of a tertiary amine the reaction gives tertiary esters, as Eq. (23) shows. [Pg.566]

Carboxylic esters where R is methyl or ethyl can be cleaved by heating with lithium iodide in refluxing pyridine or a higher boiling amine. " The reaction is useful where a molecule is sensitive to acid and base (so that 10-10 cannot be used) or where it is desired to cleave selectively only one ester group in a molecule containing two or more. For example, refluxing O-acetyloleanolic acid methyl ester... [Pg.521]

For aromatic amines, the reaction is very general. Halogen, nitro, alkyl, aldehyde, sulfonic acid, and so on, groups do not interfere. Since aliphatic amines do not react with nitrous acid below a pH of 3, it is even possible, by working at a pH of 1, to diazotize an aromatic amine without disturbing an aliphatic amino group in the same molecule. ... [Pg.816]

No stereoselectivity was observed in the formation of a 1 1 diastereomeric mixture of 2-hydroxy-2-phenylethyl p-tolyl sulfoxide 145 from treatment of (R)-methyl p-tolyl sulfoxide 144 with lithium diethylamide . However, a considerable stereoselectivity was observed in the reaction of this carbanion with unsymmetrical, especially aromatic, ketones The carbanion derived from (R)-144 was found to add to N-benzylideneaniline stereoselectivity, affording only one diastereomer, i.e. (Rs,SJ-( + )-iV-phenyl-2-amino-2-phenyl p-tolyl sulfoxide, which upon treatment with Raney Ni afforded the corresponding optically pure amine . The reaction of the lithio-derivative of (-t-)-(S)-p-tolyl p-tolylthiomethyl sulfoxide 146 with benzaldehyde gave a mixture of 3 out of 4 possible isomers, i.e. (IS, 2S, 3R)-, (IS, 2R, 3R)- and (IS, 2S, 3S)-147 in a ratio of 55 30 15. Methylation of the diastereomeric mixture, reduction of the sulfinyl group and further hydrolysis gave (—)-(R)-2-methoxy-2-phenylacetaldehyde 148 in 70% e.e. This addition is considered to proceed through a six-membered cyclic transition state, formed by chelation with lithium, as shown below . ... [Pg.616]

The carbodiimide of choice used to couple cystamine to carboxylate- or phosphate-containing molecules is most often the water-soluble carbodiimide, EDC hydrochloride Chapter 3, Section 1.1). This reagent rapidly reacts with carboxylates or phosphates to form an active ester intermediate, which is highly reactive toward primary amines. The reaction is efficient from pH 4.7 to 7.5, and a variety of buffers may be used, providing they don t contain competing groups. [Pg.84]

Figure 1.93 2-Bromoethylamine can be used to transform a thiol into an amine. The reaction may proceed through the intermediate formation of ethylenimine, yielding an aminoethyl derivative. Figure 1.93 2-Bromoethylamine can be used to transform a thiol into an amine. The reaction may proceed through the intermediate formation of ethylenimine, yielding an aminoethyl derivative.
For model reactions, we chose the aromatic substitution of aryl halides with nucleophiles such as phenolates or amines. The reaction parameters particularly focused upon were reaction time, selectivity, work-up procedure, and overall processing time. [Pg.138]

Although dealkylation using haloformates has been used with tertiary amines to provide intermediate carbamates, in the case of aromatic amines the reaction requires a large excess of the chloroformate, high temperatures, and long reaction times. For example, see a) J. P. Bachelet, P. Caubere, 7. Org. Chem. 1982, 47, 234 b) R. A. Olofson, D. E. Abbott, 7. Org. Chem. 1984, 49, 2795 c) R. A. Olofson, Pure Appl. Chem. 1988, 60,1715. [Pg.13]

FIGURE 2.14 Peptide-bond formation from chlorides of A-alkoxycarbonylamino acids. N-9-Fluorenylmethoxycarbonylamino-acid chlorides.41 The base is NaHCO, Na2C03, or a tertiary amine. The reaction is carried out in a one- or two-phase system. The latter is used to try to suppress formation of the 2-alkoxy-5(4//)-oxazolone that is generated by the action of the base on the acid chloride. The method is applicable primarily to Fmoc-amino-acid derivatives that do not have acid-sensitive protecting groups on their side chains. [Pg.43]

These and other interesting results allow quantitative insight into the rate of breakdown of N-(hydroxymethyl) compounds (i.e., carbinolamines (hemi-aminals)), the reaction mechanisms of which we examined in Sect. 8.7.3 (see, in particular, Fig. 8.20) [80 - 82], These carbinolamines, we recall, are major metabolic intermediates in oxidative N-dealkylation reactions resulting from cytochrome P450 catalyzed hydroxylation of the C-atom adjacent to the... [Pg.704]

The iridium-catalyzed reaction of primary amines with diols gave cyclic amines. The reaction of amine 109 with diol 110 in the presence of [Cp lrCl2]/NaHC03 catalyst gave heterocyclization product 111 (Equation 10.26) [50]. [Pg.265]

Secondary amines. The reaction of secondary amine type compounds with nitrous acid (HO NO) has been reviewed extensively by Turney and Wright (17), Ridd (18), Scanlan (19) and Mirvish (20). In a system containing (HO NO) as the nitrosating agent, the possible nitrosyl carriers are (H2O NO), (NO2 NO) and (NO+). The reactivity of (NO+) is very low and it is not considered an effective nitrosating form. Nitrous acidium ion (H2O NO+) plays a significant role only at concentrated acidic condi tions. Therefore, it seems likely that at the dilute acidic conditions that are encountered in the environment, it is nitrous anhydride (N2O3 = NO2 NO) which nitrosates secondary amines. [Pg.248]

As an extension of the use of chiral 0-phosphinylhydroxylamine 4e for stereoselective amination, the reaction of lithium enolates with 4e was also tried. However, low levels of enantiomeric purity were obtained (Scheme 47)". ... [Pg.329]

Quantitative stoichiometric gas-solid or solid-solid (these at 0 °C) acylations of amines with acid chlorides are varied (Scheme 32). However, for a clean reaction the liberated hydrochloric acid has to be neutralized by an additional gaseous or solid base that may also be a second mole of the amine. The reactions are performed in an evacuated flask or in a ball-mill, respectively. There are only minimal losses of the amides or sulfonamides upon removal of the stoichiometric coproduct with water [91]. The solid-solid reactions can be turned into sustainable 100% yield processes with optimal atom efficiency by milling stoichiometric 1 1 1 mixtures of acid chloride, aniline derivative, and K2CO3... [Pg.136]


See other pages where Amine the reaction is mentioned: [Pg.591]    [Pg.240]    [Pg.73]    [Pg.342]    [Pg.327]    [Pg.174]    [Pg.296]    [Pg.239]    [Pg.127]    [Pg.246]    [Pg.293]    [Pg.294]    [Pg.257]    [Pg.43]    [Pg.591]    [Pg.17]    [Pg.41]    [Pg.184]    [Pg.698]    [Pg.362]    [Pg.206]    [Pg.114]    [Pg.180]    [Pg.188]    [Pg.1280]    [Pg.37]    [Pg.183]    [Pg.55]   
See also in sourсe #XX -- [ Pg.249 ]




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