Ethyl bromide, derivation

The curves fell into two distinct groups. The top two curves characterize an all ethyl bromide derivative (PEB) and a derivative with 6.7 mol % of the pyridine groups substituted with n-dodecyl bromide and most of the remainder substituted with ethyl bromide (6.7% polysoap). These curves indicate highly extended molecular dimensions typical of normal polyelectrolyte behavior. Of the two derivatives, the 6.7% polysoap has a lower intrinsic viscosity but a larger increase of the reduced viscosity with concentration this result shows the intra- and intermolecular effects, respectively, of the hydrophobic attractions between the dodecyl groups. 

Methyl iodide ethyl bromide ethyl iodide, higher alkyl halides, chloroform, iodoform, carbon tetrachloride, chlorobenzene, bromobenzene, iodobenzene, benzyl chloride (and nuclear substituted derivatives)... 

Because ethyl bromide, ethyl alcohol (ethanol), etc., can be thought of as being derived from ethane by the substitution of one of its hydrogens by —Br, —OH, etc., we speak of these as derivatives of ethane, and we say that ethane is the parent hydrocarbon for a series of related compounds. 

Carbanion 239 derived from vinyl sulfone 238 was shown to be alkylated regiospecifi-cally at the a-carbon atom The carbanions 240 and 241 derived from <5-ketosulfones were shown to be alkylated at both a- and y-carbons . Alkylation of 240 gave a-alkylated products predominantly, while the a/y ratio varied markedly by change of the alkylating agent in the reaction with 241. For example, methylation with methyl iodide gave the products in the a/y ratio of 72 28, while the a/y ratio was 27 73 in the ethylation with ethyl bromide ... 

Hydroxy-5-MC (29a) was itself prepared (87) by a modification of the synthetic sequence employed in the preparation of 2-chrysenol (Figure 13). Reaction of 2-(l-(3-methylnaphthyl) ethyl bromide with the 1-lithio salt of 1,5-dimethoxycyclohexa-1,4-diene furnished the diketone 8a (Figure 18). Cyclization of the latter in polyphos-phoric acid afforded the 1-keto derivative which underwent dehydrogenation over a palladium catalyst to yield 29. 

A pressure vessel containing a tyrosine derivative dissolved in dimethyl formamide containing 2 (2 eq) was treated with the dropwise addition of ethyl bromide (1.1 eq) and then heated to 60°C for 30-minute intervals while being monitored by thin-layer chromatography (TLC). The reaction was then quenched with water and the aqueous layer extracted and then dried over Na2S04. The mixture was filtered, concentrated, and the product isolated. 

The dihydrido complex [RhH2(ri5-C5Me5)(PMe3)] forms C—H insertion products when irradiated in the presence of alkanes (ethane, propane).227,228 Reaction with CHBr3 leads to bromoalkylrhodium complexes, which on treatment with bromine give ethyl bromide or 1-bromopropane in 70-85% yield. The less stable iridium complex formed with neopentane could not be converted directly to neopentyl bromide.229 It gave, however, a mercury derivative that yielded the bromide after treatment with bromine. 

N-Methylation of secondary amines is usually accomplished either with CH20/HC02H (Leuckart/Clarke-Eschweiler reaction) or with CH20 followed by NaBH4 reduction. Methyl iodide treatment of secondary or tertiary bisben-zylisoquinoline alkaloids leads ultimately to the bis quaternary salts, and, in the presence of base, phenolic alkaloids are also O-alkylated. For example, lin-doldhamine (165) on treatment with ethyl bromide in 0.5 N ethanolic KOH gave the N,N,0,0,0-pentaethy 1 derivative (108, Section II,C,56) daurisoline was similarly permethylated with Mel and base (68, Section II,C,19). 

A mixture of cyclopropylmethyl bromide derivative (0.4 mmol), allyltributyltin (0.8 mmol), and AIBN (5 mol%) in dry benzene (3 ml) was degassed by bubbling argon gas for 30 min. The mixture was refluxed for 12 h. After removal of the solvent, aq. KF solution (5 ml) and ether (10 ml) were added to the residue and stirred for one hour. After filtration and separation, the organic layer was dried over Na2S04. After removal of the solvent, the residue was chromatographed on silica gel using ethyl acetate/hexane to afford a diallyl product [95]. 

The reaction of the sodium derivative of methylpyrazine with alkyl halides in liquid ammonia gives good yields (44-81%) of mono-alkylated products phenylation has been achieved by reaction with benzyne (generated from bromobenzene and sodamide in liquid ammonia) and gives 53% benzylpyrazine.178 The alkylation of the sodio derivative of 2-methoxy-3-methylpyrazine with methyl iodide, and of the product with ethyl bromide, gives 2-methoxy-3-sec-butylpyrazine (25) a constituent of galbanum oil.31... 

Tellurium (0-ethyl dithiocarbonate) halides are red-brown crystalline materials that are slightly soluble in aromatic and chlorinated solvents but insoluble in aliphatic hydrocarbons. In ethanol solution the compounds slowly decompose4. In the bromide derivative, the tellurium atom is surrounded by the two sulfur atoms from the bidentate dithiocarbonate and two bromine atoms, one of which belongs to a neighboring molecule. These four atoms form a planar trapezoid around the tellurium atom. The molecules are arranged in a helix held together by Te—Br—Te bridges4. 

This liberation of energy by the reaction just shown was found by Schumb 4 and his coworkers also to be sufficient to cleave the silicon-silicon bond. The action of sodium on mixtures of ethyl bromide, chlorobenzene, or n-amyl chloride with hexachlorodisilane resulted only in tetrasubstituced monosilanes and no disilane derivatives. In the same way, the silicon-oxygen-silicon bond of hexachlorodisiloxane was split by sodium in the presence of ethyl bromide or chlorobenzene and yielded only silicon tetraethyl or tetraphenyl. 

Ethyl acetoacetate, 20, 26 21, 23, 46,67 Ethyl acrylate, 20, 36 Ethyl alcohol, anhydrous, 22, 59 Ethyl benzoate, 20, 32 Ethyl bromide, 22, 59 Ethyl bromoacetate, 21, 51 Ethyl a-bromoisobutyrate, 21, 53 Ethyl /3-bromopropionate, 20, 6S Ethyl caprylate, 20, 69 Ethyl chlorocarbonate, 21, 81 2-Ethylchromone, 21, 42 Ethyl diacetylacetate, 21, 46 COPPER DERIVATIVE, 21, 45 Ethyl a,a-DIMETHYL-/3-PHENYL-/3-HY-DROXYPROPIONATE, 21, S3 Ethylene chloride, 20, 28 22, 76 Ethyl 1,16-hexadecanedicarboxy-late, 21, 48... 

Simple saturated nitriles are seldom prepared by the decarboxylation of cyano acids derived from the cyanoacetic ester synthesis (cf. method 265). However, difunctional compounds are frequently obtained by this route, as in the preparation of a-methyl-y-phenoxybutyronitrile from /3-phenoxy-ethyl bromide and ethyl methylcyanoacetate (52% over-all). ... 

Similar elimination reactions are employed in the synthesis of the benzologs of five-membered heterocyclic compounds. For example, /3-phenylethyl alcohols having hydroxyl, sulfhydryl, and amino groups in the ortbo position ate cyclized to the dihydro derivatives of benzofuran, benzothiophene, and benzopyrrole, respectively. Likewise, dehydro-halogenation of /3-(o-hydroxyphenyl)-ethyl bromide gives dihydtobenzo-furan in 72% yield. ... 

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