Diethyl 2- propane

Other 1,3-dicarbonyl compounds also exist largely in the enol form. In some examples there is an additional stabilizing factor, intramolecular hydrogen bonding. Diethyl malonate (diethyl propane-dioate) has a symmetrical enol stabilized by conjugation. The enol form is also stabilized by a very diethyl maionate favourable intramolecular hydrogen bond in a six-membered ring. 

The Knoevenagel reaction (Scheme 6.20) involves the reaction of aromatic aldehydes with a variety of molecules CH2XY. The groups X and Y may be the same or different, but are invariably electron withdrawing, so creating an activated methylene group from which the carbanion CHXY is produced. The reaction is usually carried out in pyridine solution, with piperidine as the basic catalyst. The reactions of benzaldehyde with propane-1,3-dinitrile [malononitrile, CH2(CN)2] and diethyl propane-1,3-dioate [diethyl malonate, CH.,(CO,Et)2] are illustrative. In both cases, manipulation of the CH=CX2 group in the product allows the synthesis of other compounds. 

Similarly complex 97 formed by the condensation of 2,2-diethyl-propane-1,3-diamine and 3,5-di-terf-butyl-salicylaldehyde and then with AlEtj in toluene and heptane at 100 C for 24 hrs (Scheme 6.21). This aluminum complex in the presence of isopropanol acts as initiator to produce PLA with narrow PDI (Table 6.14) [72]. 

Scheme 9.170. A representation of the alkylation of diethyl propane-1,3-dicarboxylate (diethyl malonate) with 1-bromobutane (CHjCH2CH2CH2Br) in an SN2-type process using sodium ethoxide in ethanol solution to generate the anion of the diester. The diethyl hep-tanedioate on hydrolysis undergoes decarboxylation when the dianion is neutralized.

Ethyl propane-1 1 3 3-tetracarboxylate. Cool a mixture of 320 g. (302 ml.) of redistilled diethyl malonate and 80 g. of 40 per cent, formaldehyde solution ( formalin ) contained in a 1-htre round-bottomed flask to 5° by immersion in ice, and add 5 g. (7 ml.) of diethylamine. Keep the mixture at room temperature for 15 hours and then heat under a reflux condenser on a boiling water bath for 6 hours. Separate the aqueous layer, dry the organic layer with anhydrous magnesium sulphate, and distil under reduced pressure. Collect the ethyl 1 1 3 3-tetracarboxylate at 200-215°/20 mm. The yield is 250 g. 

For example, carbon dioxide from air or ethene nitrogen oxides from nitrogen methanol from diethyl ether. In general, carbon dioxide, carbon monoxide, ammonia, hydrogen sulfide, mercaptans, ethane, ethene, acetylene (ethyne), propane and propylene are readily removed at 25°. In mixtures of gases, the more polar ones are preferentially adsorbed). 

The equivalent charge weight of TNT is calculated on the basis of the entire cloud content. FMRC recommends that a material-dependent yield factor be applied. Three types of material are distinguished Class I (relatively nonreactive materials such as propane, butane, and ordinary flammable liquids) Class II (moderately reactive materials such as ethylene, diethyl ether, and acrolein) and Class III (highly reactive materials such as acetylene). These classes were developed based on the work of Lewis (1980). Energy-based TNT equivalencies assigned to these classes are as follows ... 

The catalyst is filtered off at elevated temperature, and the filtrate is concentrated by evaporation under reduced pressure to a volume of 300 ml and added in a thin stream to 2.5 liters of diethyl ether with mechanical agitation. The precipitate is separated, washed with diethyl ether and dried in vacuo at 80° to 85°C for several hours. 325 g (96% yield) of the neutral tartrate of 1-(p-hydroxyphenyl)-2-(4-benzyl-piperidino)propan-1-ol are obtained. 

Alternatively, diazomcthanc can be added to thioxanthylium perchlorate (4) over 30 minutes at 0°C, and the reaction solution then poured into propan-2-ol. After concentration, the residue is dissolved in acetic anhydride and treated with boron trifluoride-diethyl ether complex at 0 C, to provide dibenzo[6,/]thiepin in 55 % overall yield16 (cf. Houben-Weyl, Vol. 10/4, p 834). 

With respect to the nucleophilic addition of organocopper reagents, a sharp contrast between the rigid isopropylidene glyceraldehyde and its open-chained analog, 2,3-bis(benzyloxy)propanal. was observed (compare Tables 15 and 16). With the isopropylidene-protected aldehyde a high syn diastereoselectivity could only be obtained when tetrahydrofuran was used as reaction solvent, and the diastereoselectivity dropped considerably in diethyl ether. In contrast, the latter solvent allows excellent syn selectivities in additions to the dibenzyl-protected glyceraldehyde81. On the other hand, tetrahydrofuran yields better results than diethyl ether in the... 

To a — 78 C solution of diisopinocampheyl(2-propenyl)borane [theoretically 50 mmol prepared front (+ )-a-piueue as described in Section 1.3.3.3.3.1.1.1.] in 50 mL of diethyl ether are added dropwise 3.6 mL (50 mmol) of propanal. The mixture is stirred for 1 h at —78 C and then warmed to r.t. and treated with 36.6 mL (110 mmol) of 3 N sodium hydroxide and 15 mL of 30 % hydrogen peroxide solution. This mixture is refluxed for 1 It. The organic phase is separated, washed with water and NaCI and dried over MgS04. The filtrate is carefully fractionated yield 5g (74%) 86% ee (of menthyl carbonate10), bp 130-131 "C/750Torr. 

To a — 30CC solution of 0.11 mL of methoxymethoxy-l-propene in 5 mL of THF are added 1 equiv of butyllithium in hexane. The mixture is stirred at this temperature for 1 h, then 1 equiv of Iriethylaluminum is added at — 78 °C. 1 equiv of propanal is then added and the resulting mixture is allowed to warm to r.t. The reaction is quenched at 0C with water, extracted with diethyl ether, and the product is purified by chromatography yield 90% d.r. syn/anti) >99 1. 

With 2,3-[isopropylidenebis(oxy)]propanal the facial selectivity of the allylstannane generated from tin(II) chloride, the disodium salt of diethyl 2,3-dihydroxybutanoatc, and 3-bromo-1-propene (see preceding section) is overwhelmed by the facial selectivity of the substrate97. Some selectivity was observed in coupling monosaccharide derived allylstannanes with monosaccharide aldehydes99. 

C,4Hi C1FN02) see Sertindole [[(3-chloro-4-fluorophenyl)amino]methylene]propane-dioic acid diethyl ester... 

C21H22F3N3OS 807-57-8) see Fluphenazine Y-[4-(trifluoromethyl)phenoxyJbenzenepropanamine -(Ci HiftFjNO 83891-03-6) see Fluoxetine (3-trifluoromethylphenyl)acetone (CioHgFjO 21906-39-8) see Fenfluramine (3-trifluoromethylphenyl)acetone oxime (CiijHkjFjNO, 834-19-5) see Fenfluramine [[[2-(trifiuoromethyl)phenyl]amino]methylene]propane-dioic acid diethyl ester (C 3Hi(,F3N04 23779-94-4) see Floctafenine... 

Propyl nitrate is very sensitive to impact. However, this sensitivity is lowered when adding 1 to 2% of propane, butane, chloroform, dimethyl ether or diethyl ether. 

Ethyl Propane-a,a,y,y-tetracarboxylate.—To a mixture of 1600 g. (10 moles, 1510 cc.) of ethyl malonate (Note 1) and 400 g. of 40 per cent formalin (5.3 moles) in a 5-I. round-bottom flask, cooled to 50 by immersion in ice, is added 25 g. (35 cc.) of diethyl-amine. The mixture is then allowed to come to room temperature and remain for fifteen hours, after which the flask is heated under a reflux condenser on a boiling water bath for six hours. The aqueous layer is then separated, and the residue is distilled under reduced pressure (Note 2) from a 3-I. special Claisen flask (Org. Syn. 1,40). The ester distils at i9o-2oo°/i2 mm.(2io-2i5°/2o mm.) The yield (Note 3) is 1000 g. (61 per cent of the theoretical amount). 

The explosion efficiency is one of the major problems in the equivalency method. The explosion efficiency is used to adjust the estimate for a number of factors, including incomplete mixing with air of the combustible material and incomplete conversion of the thermal energy to mechanical energy. The explosion efficiency is empirical, with most flammable cloud estimates varying between 1 % and 10%, as reported by a number of sources. Others have reported 5%, 10%, and 15% for flammable clouds of propane, diethyl ether, and acetylene, respectively. Explosion efficiencies can also be defined for solid materials, such as ammonium nitrate. 

In a degassed 250 mL round-bottomed flask equipped with a magnetic stirring bar were placed l,l -ferrocenedicarboxaldehyde (8.30 g), (lR,2S)-l-phenyl-2-(l-piperidinyl)propane-l -thiol (400 mg) and dry diethyl ether (115mL). Diethylzinc in toluene (1.1 M, 28.7 mL) was added dropwise to the mixture at 0 °C. The reaction mixture was stirred at 0 °C for 10 hours. 

An interesting pyrrolo[l,2-tf]pyrimidine was described as the product of the reaction of the heterocyclic ketene-aminals 236 that was synthesized by cyclocondensation of ketene dithioacetals 237 and 1,3-diamino propane. These compounds reacted with diethyl oxomalonate that behaves as an hetero-enophile, yielding the corresponding products 238 in acceptable to good yield (Scheme 31). A mechanism that involves an aza-ene reaction, via adduct 239 which isomerizes to ketene aminal 240 to produce the lactam ring of 238, has been proposed <1999J(P1)321>. 

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