3-Pentyl bromide

CsHioO 107-87-9) see Protionamide Sildenafil 4 pcntcnoic pivalic anhydride (CioHisQr 178327-16-7) see Abacavir pentyl bromide... 

The third synthetic route reported by Husson and co-workers 140) is as follows Amino nitrile 472 obtained from the ketal (471) was converted to the 2,6-dialkylpiperidine (473) by catalytic hydrogenation followed by alkylation with lithium diisopropylamide and pentyl bromide. Refluxing a solution of 473 in methanol containing hydrochloric acid led to the formation of 9-benzyladaline (475) in 90% yield. Debenzylation of 475 gave d/-adaline (107) in nearly quantitative yield (Scheme 59) 140). 

Pentendial, AE31 Pentylamine, AF03 Pentyl bromide, AE82 Pentyl iodide, AE85... 

Bromopentane (pentyl bromide). Use 210g (142 ml) of 48 per cent hydro-bromic acid, 60 g (33 ml) of concentrated sulphuric acid, followed by 88 g (108ml, lmol) pentan-l-ol (b.p. 135-136°C) and lOg (5.5ml) of concentrated sulphuric acid. Distil the product through a short fractionating column, and collect the 1-bromopentane at 127-130 °C (135 g, 89%). 

The phenol which is formed as a by-product in these systems also appears to have a significant effect on the mechanism since it increases the proportion of rearranged products obtained. For example, it was found that the interaction of neopentyl diphenyl phosphite with methyl bromide yielded pentyl bromides containing 4.4% of the tertiary isomer, whereas the percentage rearrangement rose to 50 in the presence of one molecular equivalent of phenol. 

Synonym -amyl bromide, monobromopentane, pentyl bromide... 

Add the pentyl bromide in ether (200 mL) at such a rate that the ether is gently refluxing. Stir for 3 h at rt. 

Pentylamine pendimethalin Pentyl bromide muscalure Pentyl chloride hexaconazole Pentyl magnesium bromide muscalure... 

S)-2,3-dihydroxypropanoic acid 5-sec-butylnonane sym- dibromoethane tert-pentyl bromide, t-C5HnBr threo- 2,3-dihydroxy-1,4-dimercaptobutane trans-2,3-dimethylacrylic acid uns- dichloroacetone v/c-triazine... 

The more reactive ft -carbon atom of ketone a,/ -dianions can be regiospecifically coupled with alkyl halides to give first lithium enolates, which are then trapped by more reactive carbon electrophiles such as allylic halides. The first example shown in Table 8 deals with the sequential /1-alkylation and ce-allylation of a ketone a,/1-dianion1 13. Thus, the dianion underwent regioselective alkylation at the ft carbon with //-pentyl bromide and then allylation with allyl bromide at the a carbon. When an excess of allyl bromide is reacted with the a, ft -dianion, the diallylated product is obtained in a good yield, whereas a threefold excess of pentyl bromide only resulted in the formation of the ft-alkylation product. Similar consecutive alkyl/allyl-type reactions are also possible for ketone a,5-dianions14. 

The second-order rate constants for the reaction of thiosulfate ion with n-pentyl bromide (equation 38) in aqueous ethanol (25/74 and 44/56, w/w) were affected similarly by cationic and anionic surfactants. CTAB increased the second-order rate constant by a factor of ca. 9-5 and NaLS decreased it slightly, but not unexpectedly, a non-ionic surfactant, polyoxyethylene(24) dinonylphenol did not significantly alter the rate constant (Bunton and Robinson, 1968). 

Aliphatic and aromatic nucleophilic substitution reactions are also subject to micellar effects, with results consistent with those in other reactions. In the reaction of alkyl halides with CN and S Oj in aqueous media, sodium dodecyl sulfate micelles decreased the second-order rate constants and dodecyltrimethylammonium bromide increased them (Winters, 1965 Bunton, 1968). The reactivity of methyl bromide in the cationic micellar phase was 30 to 50 times that in the bulk phase and was negligible in the anionic micellar phase a nonionic surfactant did not significantly affect the rate constant for n-pentyl bromide with S2O3-. Micellar effects on nucleophilic aromatic substitution reactions follow similar patterns. The reaction of 2, 4-dinitrochlorobenzene or 2, 4-dinitrofluorobenzene with hydroxide ion in aqueous media is catalyzed by cationic surfactants and retarded by sodium dodecyl sulfate (Bunton, 1968, 1969). Cetyltrimethylammonium bromide micelles increased the reactivity of dinitrofluorobenzene 59 times, whereas sodium dodecyl sulfate decreased it by a factor of 2.5 for dinitrochlorobenzene, the figures are 82 and 13 times, respectively. A POE nonionic surfactant had no effect. 

Rearrangement of the carbon chain occurs easily when halogen (X) is substituted for OH in much-branched primary alcohols or secondary alcohols having a tertiary H atom in the -position tertiary halides are formed preferentially, e.g., ter t-pentyl bromide is the main product from neopentyl alcohol ... 

CH3 ferf-butyl bromide CH2CH3 fert-pentyl bromide. H3... 

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