Methyl -2-bromopropionate

Addition to methyl acrylate. The ester required for this reaction was obtained from a 60% solution in methanol supplied by Rohm and Haas. This solution was treated with hydroquinone and washed repeatedly with 7% aqueous sodium sulfate solution to remove the methanol, and the ester was dried, filtered, and used without distillation. For the preparation of methyl -bromopropionate, hydrogen bromide... 

A bromine-terminated monofunctional poly(rerr-butyl acrylate) resulting from ATRP of rBA catalyzed by the CuBr/At, At,At, iV, lV"-pentamethyldiethylenetriamine (PMDETA) system (initial mole concentration ratios tBA methyl bromopropionate (MBrP) CuBr PMDETA CuBr2 = 50 1 0.5 0.525 0.025, 25% acetone, 60°C conversion = 96% after 6.5 h) was used as macroinitiator for block copolymerization with styrene (St) with the initial mole concentration ratios of St P(rBA) CuBr PMDETA = 100 1 1 1 at 100°C (conversion 94%). The monofunctional bromo-terminated copolymer P(rBA)-A-P(St) formed was subsequently used as a macroinitiator for a further copolymerization with methyl acrylate (MA). The polymerization was also catalyzed by CuBr/PMDETA (initial concentration ratios MA P(rBA-i>-P(St) CuBr PMDETA = 392 1 1 1), under high dilution in toluene and reached 23% monomer conversion after 3.5 h at 70°C. The experimental molecular weight (M ) of the resulting triblock copolymer P(tBA)-fo-P(St)-fr-P(MA) was 24,800 with a PDI = 1.10. Calculate the theoretical M to compare with the experimental value. 

Alkyl ketones can be prepared by the carbonylation of alkyl iodides in the presence of organoboranes. The carbonylation of iodocyclohexane with 9-octyl-9-BBN at 1 atm gives cyclohexyl octyl ketone in 65% yield[386]. This reaction is treated in Section 1.1.3.3. Methyl o-methylacetoacetate (919) is obtained by the reaction of the 2-bromopropionate 918, which has a /9-hydrogen, with CO and Me4Sn. PhjAs as a ligand gives better results than Ph3P[771]. 

Butyl acrylate has been prepared by direet esterifieaLion/ by debromination of -butyl ,/3-dibromopropionate with zinc, by treatment of either butyl /3-chloropropionate or butyl /3-bromopropionate with diethylaniline, and by the pyrolysis of butyl (3-acetoxypropionated Direct esterification and alcoholysis of methyl or ethyl acrylate have been recommended for the preparation of the higher alkyl acrylates. ... 

The reaction of ethyl a-bromoacetate with 17-keto steroids such as estrone methyl ether or dehydroepiandrosterone acetate " under standard Reformatsky conditions is stereospecific, producing the 17 -ol in up to 80% yields. Ethyl a-bromopropionate reacts similarly but the yields are somewhat lower. 

Ethyl isocyanide, 46, 76, 77 Ethyl a-(isopropylideneaminooxy)pro-pionate, from acetone oxime and ethyl a-bromopropionate, 48,120 hydrolysis of, 48,121 Ethylmagnesium bromide, use with ferric chloride in cyclization of di-chloroacetone /J-Lolylmagncsium bromide adduct to l-f>-tolyicy-clopropanol, 47,108 Ethyl a-methyl-/3-phenylcinnamate, 48, 79... 

Methyl fi-bromopropionate has been prepared by the esterification of /3-bromopropionic acid with methyl alcohol alone1 and through the use of hydrogen bromide as a catalyst,2 and by the direct addition of hydrogen bromide to methyl acrylate.2... 

One of the earliest studies to address the issue of aldehyde dia-stereoface selection in enolate condensation was performed by Matsumoto and coworkers (91). The Reformatsky reaction of methyl 2-bromopropionate and 2-phenylpropanal (98) afforded the four aldol adducts illustrated in eq. [70]. Although the aldol diastereo-... 

Rearrangement of Alkylcobalt Carbonyls Takegami et al. [25) reported that when ethyl ot-bromopropionate is treated with KCo(CO)4 in toluene at 0° in the presence of 1 atm of CO and the product cleaved with iodine, both the expected ester, ethyl methyl-malonate, and the rearranged ester, diethyl succinate, are formed, the latter in smaller quantity. At 25°, however, the succinate predominates. 

Ethyl N-benzylcarbamate, 35, 91 Ethyl 3-benzyl 2 cyano 3 methyl-pentanoate, 35, 7 Ethyl bromide, 34, 58, 36, 87 Ethyl a-bromobutyrate, 37, 44 Ethyl a bromopropionate, 35, 17, 37, 38... 

The method was originally proposed by Clemo and Metcalfe47 for the preparation of 3,5-dimethylpyrrolizidine. Condensation of ethyl (5-methyl-2-pyrrolidyl)acetate with ethyl a-bromopropionate resulted in the corresponding dicarboxylate (77), which was converted by cyclization and subsequent hydrolysis and decarboxylation into 3,5-... 

In another example of oxidation without fission, the major product obtained from the reaction of methyl 2-pyridylacetate with ethyl a-bromopropionate was not the expected indolizine (63) but its oxidation product (64). This was shown by a repetition of the reaction under nitrogen leading to (63), which subsequently could be oxidized to (64) by potassium ferricyanide (70JCS(C)1434). An oxidative dimerization at the 3-position of 1,2-dimethylin-dolizine was achieved with potassium ferricyanide (71TL1273) or palladium on charcoal in boiling xylene (81BCJ2833). 

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