Reactions with ethanolic NaOH

With brisk stirring 75mL Everclear (ethanol) is poured into the reaction flask then 75mL concentrated sulfuric acid is slowly added until incorporated. The rest of the distillation apparatus is connected and the solution slowly heated to about 140°C. Next, 150mL Everclear is dripped in slowly so as to match the approximate distillation output that one can see condensing over into the collection flask. The temperature must remain between 140-150 C. After all the ethanol has been added (which should have taken approximately 90 min) the distillate that has collected is washed with 5% NaOH solution then with water (remember that the ether will form the top layer here). The ether can then be dried through sodium sulfate and used or can be distilled to purify. 

Reaction of thioacetamide with benzaldehyde in ethanol, NaOH gave 783 that upon electrochemical oxidation afforded acrylonitrile derivative 785 together with the thiadiazoloquinoline derivative 784 (82MI199) (Scheme 137). 

Highly concentrated ether carboxylic acids with a low degree of ethoxylation even at room temperature can give an esterification reaction with the non-converted nonionic, especially with the fatty alcohol, to several percentage points. The result may be that a too low value is found for the ether carboxylate content. This mistake in analysis can be avoided by saponification of the formed ester [238]. Two hundred to 300 mg matter and ca 100 mg NaOH were weighed in a 50-ml Erlenmeyer glass, heated with 20 ml ethanol under reflux, and after cooling supplied with water to 100 ml. Afterward a two-phase titration was carried out. 

Reaction of 3,4-bis(phenylsulfonyl)-l,2,5-oxadiazole oxide isomers with ethanol and ethanethiol in basic medium gave the expected alkoxy- and alkylthio-substituted (benzenesulfonyl)furoxans, respectively <1996JHC327, 1997FES405>. Nucleophilic substitution of the sulfonyl group of 3,4-bis-(benzenesulfonyl)furoxan 222 in the presence of aqueous NaOH in tetrahydrofuran (THF) furnished the corresponding 3 -0-(3-benzenesulfonylfur-oxan-4-yl) derivative 223 in 79-92% yield (Equation 44) <2004JME1840>. 

When the 3-thiourea derivative (59) was heated in boiling ethanol for 3 h, and then the evaporated reaction mixture was treated with 10% NaOH solution at 100°C for 20 min, anhydro 2-methyl-3-mercapto-4-hydroxy-5,6,7,8-tetrahydro[l,2-6]pyridazinium hydroxide (61) was obtained (71CPB159). The mercapto group was alkylated with benzyl bromide and was treated with HgCla in boiling ethanol to yield the 3-chloromercurithio derivative. Anhydro 3,4-dihydroxy-2-methyl-5,6,7,8-tetrahydropyrido[l,2-f ]pyridazinium hydroxide (62) was O-acylated with acetic anhydride, but the structure of the product was not elucidated (71CPB159). 

For the synthesis of aminotriacetylpyrans 84 a reaction of 3-bromoace-tylacetone 85 with cyanoacetic ester in ethanolic NaOH was employed. Possibly, it proceeds via the formation of acetylacetone dimer 86... 

The presence of the enamino moiety in 2-amino-4H-pyrans accoimts for their ability to undergo recyclizations into various pyridones, 1,4-dihy-dropyridines, and 2H-pyrones-2. To some extent, properties of 2-amino-4H-pyrans in reactions with nucleophiles can be compared to those of pyrillium salts (68T5059,80T697) because they also tend to form recyclized products. Reactions proceed in the presence of bases or acids. Naphthopyrans 133 form 2-alkoxypyridines 261 on the action of sodium alcoholates or ethanolic NaOH (79M115) (Scheme 101). 

The normal reactions of benzo[6]thiophene 1,1-dioxides have been reviewed (70AHC(11)177). Electrophilic substitution (nitration, bromination) takes place at position 6. 3-Halo derivatives undergo normal nucleophilic displacement reactions, but 2-bromobenzo[6]thiophene dioxide gives the 3-ethoxy derivative in ethanolic NaOH. The reaction of 3-methoxy derivatives with secondary amines can give rise either to enamines... 

Favorskii-type reactions, which are known to be sensitive to the base and solvent used and to the nature of the halogen leaving group, continue to attract attention, and in combination with other bond forming processes can often be manipulated to provide useful synthetic methods. For example, the chloroketone 1 gives pivalic acid on treatment with 40% aqueous NaOH, but only 3-hydroxy-3-methyl-2-butanone on reaction with either 20% aqueous Na2CC>3 or 14% aqueous or ethanolic KOH. When a mixture of 1 (3.5 eq.) and benzaldehyde (1 eq.) was treated with 14% ethanolic KOH (7 eq.) at room temperature for 3 hours, however, the lactone 2 was the major... 

Oligo(ethyleneimine) Resin (20). A cold (0°) solution of the chlorosul-fonylated resin (18)77 (15 g, 0.12 mol) in dimethoxyethane (40 ml) was treated with a dimethoxyethane solution (20 ml) of triethylenetetraamine (0.596 mol) dropwise. The resulting reaction mixture was allowed to stir for 24 h at RT. Upon filtration, the hydrochloride salt form of the resin formed was washed with ethanol (20 ml) followed by water in excess amounts. The resin was further washed with a 5% NaOH solution (100 ml) under stirring for 30 min. Upon decantation, water (100 ml) was added and the resulting mixture was boiled for 30 min. The reaction mixture was filtered and washed successively with water in excess followed by ethanol (20 ml). The resin was then dried under vacuum at 40° for 24 h. 

B) Preparation of 7-Allyloxy-4,8-Dimethylcoumarin 7-Hydroxy-4,8-dimethylcoumarin (191.3 g, 1.01 mols), anhydrous potassium carbonate (604 g, 4.37 mols), and allyl bromide (578 ml, 6.22 mols) were refluxed overnight in acetone (ca 3 liters) with mechanical stirring. The reaction mixture was concentrated nearly to dryness on a steam bath under reduced pressure, water (ca 8 liters) was added, and the product was collected by filtration. It was washed with 5% NaOH and water (ca 1.5-liter portions) and was dried in a vacuum desiccator. The dry solid was washed with petroleum ether (30° to 60°C) to remove excess allyl bromide. Removal of the petroleum ether under reduced pressure left 210.0 g (90.7% yield) of product. The 7-allyloxy-4,8-dimethylcoumarin was crystallized from aqueous ethanol as colorless needles, MP 108° to 109°C. 

Give the products resulting from the following reactions (a) 2-naphthol + MCN + ZnCI, + HCl (b) anthracene + cA-butene-dioic anhydride (c) nap ht ho-1.4-quin one + hcxa-2.4-dicne follow cd by reaction with CrO (d) naphthalene + phihalic anhydride -i-AlCl followed by reaction with polyphosphoric acid and then reduction and dehydlogenation (e) 1-tetralone + benzaldehyde + NaOH in ethanol. 

Bulmus et al. (1997) demonstrated the modified PMMA mono-size microbeads for glucose oxidase immobilization, in which PMMA substrate was washed with 10% (w/v) NaOH followed by 50% (v/v) ethanol. Freshly cleaned PMMA was then immersed in a solution of 1 g/L polyvinyl alcohol for 20 min, followed by oxidation reaction with a solution of 1% NaI04 for 1 h at room temperature. The amino functionality was then added by using a solution of 10% (w/v) hexamethylene diamine in 100 mM borate buffer pH 11.5, for 2 h (123) (shown in scheme 8.5). 

To 25.0 ml of freshly voided urine is added 5 N NaOH with stirring until it is just alkaline to phenolphthalein paper. The solution is filtered through filter paper, and to 20.0 ml is added 5 ml of buffer (8.4 g NaHCOa dissolved in about 80 ml of H2O the pH is adjusted to 8.8 with 5 N NaOH and diluted to 100 ml with H2O). To this mixture is added 2.0 ml of freshly prepared 2,4-dinitrofluorobenzene (10% in ethanol w/v) and 40.0 ml of ethanol. Mix well and keep in a dark cabinet with occasional stirring for about an hour. The reaction mixture is cooled to room temperature and the pH adjusted with 5N NaOH to about 12.0. The mixture is transferred to a 100-ml separatory funnel and extracted three times with 10-ml portions of ether to remove excess reactant the ether phases are discarded. 

In addition a paper should be mentioned, which provided extremely interesting results, although with inadequate evaluation. In [545] the competitive parallel reaction proposed by Bourne (neutralization -)- ester saponification) was carried out in four differently sized (D = 0.14 0.29 0.61 0.91 m H/D — 1), geometrically similar, baffled vessels with turbine stirrers. Ethanol yield YEtoH = [EtOH]/[NaOH]o was determined as a function of the tip speed of the stirrer Ttnd, the volume-related power P/V and the mixing time 9. It was found that in all four differently sized vesels similar Yeioh values were realized, if the mixing time 9 was kept constant. The number and the position of the feed points was also found to have a strong effect. The reaction partner, here NaOH, should be added as near as possible to the stirrer. 

Dichlorovos may be prepared in several ways. Methanol is treated with chloral (CCI3-CHO) and PCI3 to get dimethyl-l-hydroxy-2,2,2-trichloroethyl phosphate (55), which is heated with 25% NaOH to yield dichlorovos (23) [60]. Alternatively, chloral alcoholate (56), the precursor of chloral prepared by passing chlorine into cooled ethanol, is allowed to react with (MeO)jP to form dichlorovos [61]. In another approach, methanol is treated with PCI3 to get (MeO)3P (57) [62]. This reaction may also be carried out in the presence of CuCl at - 10 C to yield the adduct (MeO)3P.CuCl (58) [63]. Reaction of 57 or 58 with chloral yields dichlorovos (23) [62,63]. 

An approach to carbocyclic arenes by cyclative cleavage is presented in Scheme 37 [53]. Merrifield resin was etherified with 3-hydroxypyridine (140), and then the pyridine moiety was quaternized with bromoacetone to yield 141. Formation of an yhde 142 with NaOH/ethanol and subsequent reaction with a chalcone (143) produced the intermediates 144 after a Michael addition. A subsequent condensation reaction released the phenolates 145 from the solid phase with restoration of the pyridine moiety on the solid support. Acidic work-up and filtration furnished... 

Primary amine formation is equally well promoted in alkaline medium, e.g., aqueous ethanolic NaOH solution, that selectively poisons the catalyst for hydrogenolysis reactions. However, saturated NH3/alcohol solutions best afford almost quantitative yields of primary amines from catalytic reduction of nitriles. Ammonia adds to imine 1 to give a 1,1-diamine, which is hydrogenolyzed to the primary amine. In the presence of NHj, finely divided Ni can be used, platinized finely divided Ni for the hydrogenation of hindered nitriles, and rhodium-on-alumina for sensitive compounds. Mild reduction of 3-indoleacetonitrile to tryptamine [equation (c)] is effected at RT over 5% rhodium-on-alumina in 10% ethanolic NH3 with little side reaction , and branched chain amino sugars are conveniently prepared using this selective hydrogenation [equation (d)] . 

The freshly cleaned crystal is immersed in an unstirred 1 mM ethanolic solution of 11-mercaptoundecanol at room temperature, in the dark, for 48 h. The solution of 11-mercaptoundecanol is freshly prepared before use (2 mg of the thiol in lOmL of ethanol). The crystal is then washed with ethanol and milliQ water and sonicated for 10 min in ethanol to remove the excess of thiol. The hydroxylic surface is treated with a 600 mM solution of epichlorohydrin in a 1 1 mixture of 400 mM NaOH and bis-2-methoxyethyl ether (diglyme) for 4h. After washing with water and ethanol, the crystal is immersed for 20h in a basic dextran solution (3g of dextran in lOmL of NaOH lOOmM). The surface is further functionalized with a carboxymethyl group using bromoacetic acid (1M solution in 2M NaOH for 16h). All the reactions are performed at room temperature. The coated crystals can be stored at 4°C immersed in milliQ water for 15 days. For their use, the crystals are washed with water and placed in the cell. 

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