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With malonate esters

Z-Furan. 3-(5-Nitro-2-furanyl)-2-propenamide, is prepared by condensation of 5-nitro-2-furancarboxaldehyde diacetate with malonic ester followed by PCl chlorination and amination (29). The product was marketed in Japan as a food preservative. [Pg.460]

This reaction follows an lomcchammechamsmfree equation 15)(equation 110) The reaction ot perfluoroisobutylene with malonic esters affords fluonnated... [Pg.476]

This makes the nitrogens electron poor, and they should not act as either bases or nucleophiles. Nevertheless, urea reacts with malonic esters to make barbiturates. A key step in this reaction involves nucleophilic attack by the urea nitrogen on the malonic ester. [Pg.153]

Condensation of Af-aryliminochlorides with malonic ester followed by thermal cyclization, as initially reported by Just, was found to be a general method for the preparation of 2, 3, 4-substituted quinolines. Various substituents on the aryl ring of the iminochloride proved uneventful, even though the conditions required to generate the iminochloride utilized PCI5. [Pg.425]

Amidines can also react with malonic ester derivatives to provide pyrimidines. A... [Pg.537]

An other procedure for constructing this ring system started with 2-methylbenzimidazole 583 whose reaction with malonic ester 584 gave 585... [Pg.144]

One frequently used method for synthesizing 2-quinolones is to react anilines with malonic esters. This reaction can be difficult to accomphsh by conventional methods [48,49] since high temperatures (250-350 °C) are required for the generation of an o -oxoketene intermediate 12 (Fig. 6). In a recent example of this type of reaction, Stadler et al. synthesized 4-hydroxyquinolin-2(lH)-ones by using a microwave-assisted procedure (Scheme 5) [50]. [Pg.317]

The cz5-aziridine substrate shows, as expected on the basis of this model, predominant formation of the trans-cyclopropane product. The starting materials for this MIRC reaction can readily be obtained from the aziridine esters by reduction to the corresponding aldehyde and a subsequent Knoevenagel reaction with malonate ester (Scheme 25) [34]. [Pg.108]

The above method is adapted from the procedure of Day and Thorpe.1 /3-Methylglutaric acid has been prepared by hydrolysis of jS-methylglutaronitrile 2 by condensation of crotonic ester with ethyl sodiocyanoacetate, and with sodiomalonic ester 3 4 and by condensation of acetaldehyde with malonic ester. ... [Pg.31]

These model reactions were of great value in the extension of the C-glycosylation reaction with malonic esters to five-membered ring-systems. Treatment of 2,3 5,6-di-O-isopropylidene-a-D-manno-furanosyl bromide122,123 (150) with diethyl sodiomalonate led to an anomeric mixture of C-glycosyl compounds that could be separated by column chromatography, with the a (151) and /B (152) anomers in... [Pg.148]

This reaction was easily performed with malonic ester derivatives using approaches described above for nitro carbanions. It should be noted that the anion of malonic ester can be prepared not only by the reactions of bases with malonates but also by desilylation of silyl ketene acetal (449) with fluoride anion. [Pg.675]

Scheme 9.12 Intramolecular allylic alkylations with malonic ester derivatives. Scheme 9.12 Intramolecular allylic alkylations with malonic ester derivatives.
With malonic esters and amides substituted at the central carbon, triazole formation is accompanied by decarboxylation and 4-alkyl-or 4-aryl-5-hydroxytriazoles are isolated. ... [Pg.45]

Tosylation of 1146 gave 1147, which was converted to the iodo derivative, whose reaction with the sodium salt of guanine, followed by acetylation to aid its purification and then deprotection, gave 1148 (86JMC1384). The hydroxymethyl groups on C-5 of barbituric acid were introduced starting with malonic ester and then reaction with urea (93MI12). [Pg.186]

The preparation of barbiturates illustrates many of the synthetic methods covered in this chapter. The preparation employs the reaction of urea (C0(NH2)2) with malonic ester to form barbituric acid. The general reaction is presented in Figure 15-30. The stable pyrimidine and other resonance forms help drive the reaction. By alternating the substituent at carbon number five (C5), various pharmacologically active substances can be formed. Barbital, a sedative, and phenobarbital, a sleeping aid, are shown in Figure 15-31. [Pg.279]

Dihydro-4H-l,2-diazepines (34) have been prepared in good yields by the reactions of a -bromoazines (33) with malonic esters in the presence of base (77BCJ2153). [Pg.598]

As with malonic ester (Problem 17.13), either one or two R s can be introduced in acetoacetic ester. [Pg.394]

Likewise, the ditosylate 6 reacts with malonic ester to afford the spiro diester 7. Interestingly, similar consecutive synthetic steps allow for elongation of the molecule, furnishing eventually the bis-spiro compound 9.20,21... [Pg.78]

Acceptable yields have been obtained for dialkyl 3,3-dimethoxycyclobutane-l,l-dicarboxylates which are functionalized at Cl and C3 by reaction of l,3-dibromo-2,2-dimethoxypropane (10) with malonic esters.22 In these reactions, dimethylformamide proves to be the solvent of choice, because it allows the volume of the reaction mixture to be kept to a minimum.22 High temperature (120 to 130 C) is also necessary for these reactions due mainly to the solubility... [Pg.78]

Table 8. Electrogenerated superoxide reaction with malonate esters ... Table 8. Electrogenerated superoxide reaction with malonate esters ...
Certain pyrones react with active hydrogen compounds in a quite different way they display their alkenic character by a Michael reaction. Thus, coumarin yields (301) with malonic ester. [Pg.214]


See other pages where With malonate esters is mentioned: [Pg.162]    [Pg.540]    [Pg.871]    [Pg.875]    [Pg.425]    [Pg.204]    [Pg.244]    [Pg.166]    [Pg.104]    [Pg.392]    [Pg.545]    [Pg.149]    [Pg.332]    [Pg.71]    [Pg.150]    [Pg.291]    [Pg.540]   
See also in sourсe #XX -- [ Pg.55 ]




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2- malonic ester, reaction with urea derivatives

Alkyl halide malonic ester synthesis with

Esters allylic, reaction with malonate

Malonate esters

Malonate esters, addition with

Malonic acid, half-ester, reaction with

Malonic ester, acetyl-, reaction with

Malonic esters condensation with

Malonic esters reaction with hydrazines

Malonic esters, 2-halo-, reaction with

Malonic esters, acylation with

Malonic esters, acyliminoreactions with organometallic compounds

Malonic ester—

Michael with malonic acid ester

Nitriles, condensation with malonate esters

Reaction with malonic esters

Ricinoleic acid reaction with malonic esters

Salicylaldehyde reaction with malonic esters

Sodium ethoxide, reaction with malonate esters

Sulfones, alkylation with malonate esters

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