2-methyl-2-propyl bromide

Electrostatic potential map for bromide+2-methyl-2-propyl bromide shows most negatively-charged regions (in red) and less negatively-charged regions (in blue). 

Calculate activation barriers for bromide addition t( methyl bromide, ethyl bromide, 2-propyl bromide an( 2-methyl-2-propyl bromide using energies for Sn transition states bromide+methyI bromide, bromide- ethyl bromide, bromide+2-propyl bromide and bromides 2-methyl-2-propyl bromide) and Br (at left). Whicl reaction is fastest Slowest ... 

Examine space-filling models of ethyl bromide and 2-methyl-2-propyl bromide. Given that Sn2 reactions require backside attack, which of these is more likely to react with EtO in an Sn2 fashion What will the product be What E2 products would be obtained from each alkyl bromide ... 

Telluronium Allyl bis-[2-methyl-propyl]- (Bromide) E12b, 683 (R2Te -f Allyl-Br)... 

Cool the mixture and decant the solution from the sodium bromide wash the salt with two 20 ml. portions of absolute alcohol and add the washings to the main solution. Distil off the alcohol, which contains the slight excess of n-propyl bromide used in the condensation, through a short fractionating column from a water bath. The residue A) of crude ethyl n-propylacetoacetate may be used directly in the preparation of methyl n-butyl ketone. If the fairly pure ester is required, distil the crude product under diminished pressure and collect the fraction boihng at 109-113727 mm. (183 g.) (R). 

The rate of acetolysis of t-butyl bromide relative to that of i-propyl bromide at 25°C is 10 - , whereas the rate of acetolysis of 2-methyl-2-adamantyl bromide relative to that of 2-adamantyl bromide is 10 ... 

The search for opioid analgesics which show reduced addiction liability ha.s centered largely on benzomorphan and morphinan derivatives. Some research has, however, been devoted to derivatives of the structurally simpler meperidine series. The preparation of one such compound, picenadol (59), starts with the reaction of N-methyl-4-piperidone with the lithium derivative from m-methoxybromobenzene. Dehydration of the first formed carbinol 51 gives the intermediate 52. Deprotonation by means of butyl lithium gives an anion which can be depicted in the ambident form 53. In the event, treatment of the anion with propyl bromide gives the product 54 from reaction of the benzylic anion. Treatment of that product, which now contains an eneamine function. 

Bromomethane, see Methyl bromide Bromopentane, see Amyl bromide Bromopropane, see Propyl bromide 3-Bromopropene, see Allyl bromide 3-Bromopyne, see Propargyl bromide ... 

Synthesis of Compound I. As shown in Scheme II, 3-(thiophene-3-yl)propyl bromide can be prepared by a two-carbon homologation(2 ) of 3-thenyl bromide via reaction with diethyl malonate to form diethyl 3-thenylmalonate. This is followed by saponification, decarboxylation, reduction of acid to alcohol, (2 ) and replacement of the hydroxyl group with bromide by reacting with PBr3.(22) Compound 2 is synthesized by mono-quaternization of an excess of 4,4 -bipyridine with 3-(thiophene-3-yl)propyl bromide followed by N-methylation with CH3I. All the intermediates in Scheme II have been identified by NMR spectroscopy. 2 has been characterized by NMR and high resolution mass spectroscopy and by electrochemistry. 

On the basis of products formed in a number of condensation reactions only confusion results for any step by step mechanism involving specific identifiable species as intermediates. Here are some of the facts. Benzene condenses with cyclopropane to form n-propylbenzene (Simons et al., 44). Normal propyl bromide gives chiefly isopropyl benzene (Simons and Archer, 36) as does propylene (Simons and Archer, 28). Ethyl alcohol gives ethylbenzene, but methyl alcohol does not give... 

Analog laBt sich beispielsweise durch Kondensation von Benzaldehyd mit (5)-2-Amino-l-hydroxy-3-methyl-butan und Reaktion des so erhaltenen Imins mit Ethyl-magnesium-bromid ein Gemisch von zwei diastereoisomeren l-( l-Methoxymethyl-2-methyl-propyl-amino)-l-phenyl-propanen in 81 %iger Ausbeute erhalten3. 

All data obtained on the rate of reaction of [Ni(NiL2)2]Cl2 with alkyl halides— i.e., methyl iodide, benzyl bromide, benzyl chloride, p-nitrobenzyl chloride, p-chlorobenzyl chloride, ethyl bromide, ethyl iodide, n-propyl bromide, and n-propyl iodide—conform closely to a pseudo-first-order rate law. Almost all experiments were carried out in the presence of an excess of alkyl halide. Since methanol solutions of the alkylated complexes have only negligible absorption at 495 m//, rates were obtained by graphs of log A0—A vs. time. The graphs are linear over the entire time interval, which corresponds to more than two half lives in most cases, passing through the origin at zero time. The rate is essentially the same whether measured by the spectrophotometric or conductivity method. 

Bromopentane. Proceed as for n-Amyl Bromide, but use 88 g. (108 ml.) of methyl -propyl carbinol (2-pentanol), b.p. 118-5°. During the washing with concentrated hydrochloric acid, difficulty may be experienced in separating the acid layer this is overcome by adding a little water to decrease the density of the acid. Distil the purified product through a fractionating column some amylene passes over first, followed by the 2-bromopentane at 115-118° (120 g.). 

Methyl -propyl ketone, 340 Methyl pyridines, purification of, 177-179 N-Methylpyrrole, 837, 838 Methyl red, 621, 625 sodium salt of, 626 Methyl salicylate, 780,782 Methyl sulphite, 304 2-Methylthiophene, 836 Methyl p-toluenesulphonate, 825 Methylurea, 968, 969 Methylene bromide, 300 Methylene chloride, purification of, 176 3 4-Methylenedioxycinnamic acid, 711, 719... 

Schulte and Witt103 described the products obtained from the pyrido-[l,2-a]pyrimidine (63 R = H) with propargyl bromide and with 1-bromo-but-2-yne in methanolic potassium methoxide as the 2-alkoxy derivatives (mp = 200 C). Later, Katritzky and Waring273 proved these compounds to be the 1-alkyl derivatives. From 63 (R = H) with methyl iodide they obtained the 1-methyl derivative with propyl bromide, the 2-propyloxy derivative and with propargyl bromide, a mixture of the 1-propargyl and 2-pro-pargyloxy derivatives. 

Southern corn rootworm. The structure of the southern corn rootworm has been defined as 10-methyl 2-tridecanone, XI (Figure 16) (5J3). Alkylation of undecanoic acid with n-propyl bromide was followed by conversion to the diastereomeric amides with either (S)- or (R)-a-methylbenzylamine that had been purified previously by recrystallization of D and L tartaric acid salts, respectively. Recrystallizations of these amides from ethanol (4 was sufficient) gave 32% yields of pure (>99.5%) diastereo-mers (Figure 16). Hydroxyethylation labilized the amides toward hydrolysis. It was convenient to intercept the aminoesters and reduce them with LAH. The resulting carbinols were than carried forward in standard manner to provide the ketones. 

Foster and Wolfrom, in 1956, encountered an anomalous reaction of methyl 3,4-0-isopropylidene-2-0-(sodium thiolthiocarbonyl)- S-D-arabino-pyranoside (LIX) with certain alkyl halides, namely ethyl iodide, propyl bromide, isopropyl bromide, and ter<-butyl chloride. The expected 2-0-[(alkylthio)thiocarbonyl] esters LX were not formed, but, in each case, bis(methyl 3,4-0-isopropylidene-j8-D-arabinopyranoside) 2-thionocarbonate (VI) was isolated. A probable explanation of this behavior was suggested... 

In the present instance, the product is a tertiary alcohol whth two methyl groups and one propyl group. Starting from a ketone, the possibilities are addition of methyl-magnesium bromide to 2-pentanone and addition of [)rop Tmagnesium bromide to acetone. 

The effect of the electron scavenger, CS2, is explained as due to preventing the neutralization of the cations in the system and subsequent reaction of in the state with cyclopropane or with the radiolytic products of the substrate. In the presence of CS2 the major product is methyl iodide similarly to the major product of Br found by De Jong and coworkers . However the analog to the main product in the case of I2 or O2 as scavenger, namely, n-propyl bromide was not found at all by De Jong and co workers. They found the second and third major products to be allyl bromide and cyclopropyl bromide while Certout and Schleifer did not find the respective iodides at all. It is not clear if this is due to the difference between Br and I or due to the different amount of radiolysis induced by each of them. 

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