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General synthesis procedures

Polymer Synthesis. General Procedure—All polymers were prepared by free-radical-initiated solution polymerization. Typical quantities utilized were as follows 5.0 g total monomer and 0.02 g AIBN or Vazo 33 in 30-60 mL solvent. More dilute solutions were employed in some cases to eliminate gel formation. In addition, a chain transfer agent, dodecanethiol, was used to control molecular weight in some polymerizations. [Pg.190]

Automated Stepwise Solid-Phase Peptide Synthesis General Procedure 177-791... [Pg.76]

Synthesis of Alkviamines. General Procedures. Method (A). The synthesis of p-phenethylamine is representative. A flame dried, nitrogen-flushed, 100 ml flask, equipped with a septum inlet, magnetic stirring bar and reflux condenser ivas cooled to 0°C. Sodium borohydride (9.5 mmol, 0.36 g) was placed in the flask followed by sequential addition of THF (13-15 ml) and BF3-Et20 (12 mmol, 1.5 ml) at 0°C. After the addition, the ice bath was removed and the contents were stirred at room temperature for 15 min. The solution... [Pg.139]

Alkvl Azides from Alkyl Bromides and Sodium Azide General procedure for the synthesis of alkyl azides. In a typical experiment, benzyl bromide (360 mg, 2.1 mmol) in petroleum ether (3 mL) and sodium azide (180 mg, 2.76 mmol) in water (3 mL) are admixed in a round-bottomed flask. To this stirred solution, pillared clay (100 mg) is added and the reaction mixture is refluxed with constant stirring at 90-100 C until all the starting material is consumed, as obsen/ed by thin layer chromatographv using pure hexane as solvent. The reaction is quenched with water and the product extracted into ether. The ether extracts are washed with water and the organic layer dried over sodium sulfate. The removal of solvent under reduced pressure affords the pure alkyl azides as confirmed by the spectral analysis. ... [Pg.156]

The above synthesis, although performed on a small scale, is easily scaled up to industrial size (French Pat. 2,669,922, CA 118 P6734U). It is a general procedure for substituting aryl-Br with -OMe or -OEt, giving us the possibility to produce other compounds from already known substances, e.g bromination of MDA yields 6-Br-MDA. This is converted by the above procedure to MMDA-2, 133, active at 25-50mg, 8-12 hrs. [Pg.178]

Synthesis of large heterocycles usually involves condensation reactions of two difunctional molecules. Such molecules tend to polymerize. So far two special techniques have been described above to avoid this important side-reaaion , namely high dilution and use of templates. The general procedure to avoid polymerizations in reactions between difunctional molecules is, of course, the application of protecting groups as described in sections 4.1.2 and 2.6. [Pg.248]

The same general procedure was applied satisfactorily to the synthesis of 2-bromothiazoles using hydrogen bromide below 0°C (465, 507) (Table 11-29). [Pg.274]

The comparatively ready accessibility of selenocarboxamides has encouraged the use of this procedure for the synthesis of selenazoles (1889LA(250)294). Reaction of the a-chloro-carbonyl compound (73) with the selenocarboxamide (74) provided a ready synthesis of a variety of substituted selenazoles (75). Useful variations of this general procedure are described in detail in Chapter 4.20, and particularly attractive is the reaction of hydrogen selenide with a mixture of a nitrile and the a-halogenoketone to afford the selenazole (48YZ191, 79S66). [Pg.118]

Although heating benzene-1,2-diamine with malonic acid in aqueous hydrochloric acid affords the parent dione 26 (R = H) in 62% yield,277 the method cannot be extended to substituted malonic acids because decarboxylation intervenes however, the reaction of benzene-1,2-diamines with diethyl malonate and its derivatives constitutes a general procedure for the synthesis of l,5-benzodiazepine-2,4-diones 26 selected examples are given.278... [Pg.425]

Oxidation of phenyl hexyl sulphide with sodium metaperiodate gave also only a trace amount of the corresponding sulphoxide72. On the other hand, Hall and coworkers73 prepared benzylpenicillin and phenoxymethyl penicillin sulphoxides from the corresponding benzyl esters by oxidation with sodium metaperiodate in dioxane solution with a phosphate buffer. A general procedure for the synthesis of penicillin sulphoxides was reported later by Essery and coworkers74 which consists in the direct oxidation of penicillins or their salts with sodium metaperiodate in aqueous solution at pH 6.5-7.0. 1-Butadienyl phenyl sulphoxide 4475 and a-phosphoryl sulphoxides 4576 were also prepared by the same procedure. [Pg.246]

General Procedures for the Synthesis of the Pyridone Sulfonates VIa,b,c and VIIa,b,c (25). A solution of 1.25 mmol of the sodium salt of 3-carbamoyl-2(lH)pyridone(III) or 3-phenyl-2(lH)pyridone and 1.25 mmol of the corresponding bromosulfonate sodium salt in 50 mL of acetonitrile was brought to reflux and stirred for 24 h. The reaction mixture was cooled and filtered through a sintered glass... [Pg.225]

General procedures for the synthesis of ligands and metal complexes are shown in Scheme 1. For file synthesis of 2a acenaphthenequinone (0.38 g, 2.1 mmol) and a,a-bis(4-amino-3,5-dimethylphenyl)-toluene(Kccess) were dissolved in 50 mL of CH3OH in a round-bottom flask. Five drops of formic acid were added, and the sealed solution was stirred at 50 C overnight. After filtration, the red solid was washed with hot methanol and dried to give 1.2 g of red powder in 50 % yield. [Pg.857]

The synthesis of di- or tri-nudear pentafluorophenyl derivatives by the use of polydentate ligands with [AulCgFsjltht)] is quite a general procedure as shown in Table 3.4. Many of these complexes have been characterized by X-ray diffraction and show short Au Au contacts as in [(CgFsjAulSdppmSjAulCfiFs)] [88] of 3.163(1) Aor in the dinuclear complex [57] shown in Figure 3.8 of 3.4671(9) A. [Pg.108]

When [ H]-labeled precursors are employed the resulting compounds can be used as internal standards for analysis, especially by utilization of mass spectrometric methods. Appropriate deuterated standards are shown in Fig. 7. The introduction of deuterium into the A9-THC precursors can be done with Grignard reagents such as C[ H3]MgI or reducing substances such as LiAl[ H4]. The general procedures for the synthesis with these [ Hj-labeled precursors are the same as described above for the unlabeled compounds [76,78]. [Pg.23]

General procedure for the reaction of an o-substituted aryl iodide and a terminal olefin. Synthesis of vinylbiphenyls. [Pg.456]

The general procedure used for the synthesis of [l,2,3]triazolo[l,2-tf][l,2,4]benzotriazin-l-5(6//)-dione derivatives 506 is shown in Scheme 86. Ionic 1,3-dipolar cycloaddition of the appropriate azide 503 to ethyl phenylacetates gives l-(2-nitrophenyl)-4-aryl-5-oxo[l,2,3]triazoles 504. Catalytic reduction of these compounds affords the corresponding amines 505. Cyclocondenzation of these amines to the final tricyclic compounds 506 is performed using triphosgene in anhydrous tetrahydrofuran solution at room temperature (Scheme 86) <2005JME2936>. [Pg.438]

Data from this laboratory and others8,9,10 indicate that the general procedure outlined for the synthesis of F2PX compounds may be extended to the synthesis of the oxy derivatives of pentavalent phosphorus such as F2C1P0 and Cl2FPO, but the detailed directions are not given here. The mixed oxyhalides of phosphorus, like the corresponding mixed halophosphines, have not been obtained easily in pure form from complex reaction mixtures.11,12... [Pg.150]

A related support frequently used for liquid-phase synthesis is methoxy-polyethyl-ene glycol (MeO-PEG). The group of Taddei has presented a general procedure for... [Pg.340]

General procedures for the synthesis of the imidazole core have been published in 2000. Solvent-free microwave assisted synthesis of 2,4,5-substituted imidazoles 64 from aldehydes 62 and 1,2-dicarbonyl compounds 63 in the presence of ammonium acetate and alumina has been reported <00TL5031>. V-protected a-amino glyoxals 65 were utilized as potential chiral educts for the synthesis of amino acid-derived imidazoles 66 <00TL1275>. [Pg.172]

A recently developed general procedure for the synthesis of cyclic nitroso acetals is based on the reaction of cyclic nitronates with C-nucleophiles under conditions of electrophilic catalysis (Scheme 3.153 for more details, see Section 3.5.2.3). [Pg.571]

Cyclization by addition of a side-chain carbanion to an aryne bond has been proposed as the method of choice for synthesis of the versatile 1-substituted benzocyclobutene system.7 This general procedure now has been modified to permit convenient large-scale preparations utilizing a commercially available base, a minimum amount of liquid ammonia, and distillation for isolation of the product. [Pg.115]

General procedure for the synthesis of telluroselenoethenes from acetylenic selenides... [Pg.141]


See other pages where General synthesis procedures is mentioned: [Pg.123]    [Pg.139]    [Pg.521]    [Pg.105]    [Pg.145]    [Pg.126]    [Pg.546]    [Pg.19]    [Pg.854]    [Pg.165]    [Pg.379]    [Pg.79]    [Pg.150]    [Pg.303]    [Pg.182]    [Pg.558]    [Pg.34]    [Pg.34]    [Pg.715]    [Pg.142]    [Pg.142]    [Pg.143]   
See also in sourсe #XX -- [ Pg.201 ]




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