Methyl 5-bromovalerate

This method with some slight modihcations is applied in the synthesis of to-bromo esters from Cs to Cn. Methyl 5-bromovalerate has been prepared by treating the silver salt of methyl hydrogen adipate with bromine. The ethyl ester has been prepared from the acid by esterification or through the acid chloride. ... 

Methyl /3-brohopropionatk, 20, 64 Methyl 5-bromovalerate, 26, 52 Methyl- -butylamine, 25,19... 

The Step 3 product (0.89 mmol) and methyl 5-bromovalerate (0.98 mmol) dissolved in 3.3 ml acetonitrile were treated with K2C03 (1.95 mmol), then refluxed 48 hours, and concentrated. The residue was dissolved in EtOAc, then washed with water, dried using Na2S04, and concentrated. The residue was purified by chromatography using cyclohexane/EtOAc, 5 1, and the product isolated in 78% yield as a colorless oil. 

METHYL 5-BROMOVALERATE (Valeric acid, 6-bromo-, methyl ester)... 

An Algox Pharmaceutical group reported a preparation of MNA capitalizing on a C5 + C5 strategy, and based on the alkylation of bromovaleric add (S2) with the lithium anion of 3-methyl-l-butyne (S3), followed by stereoselective reduction of 8-methyl-6-noninoic acid (S4) to ( )-MNA by dissolving-metal reduction. 

C2H5I + Na2Fe(CO)4 + BrECHJ COOCaHs -> C H COICH COOC H Ethyl 5-bromovalerate added under Ng to a soln. of Na-tetracarbonylferrate(-II) in N-methyl-2-pyrrolidone, stirred 1 hr., ethyl iodide added, and the product isolated after 24 hrs. ethyl 6-ketooctanoate. Y 74%. - The most remarkable feature of the above reagent is its toleration of functional groups. F. e., also with tosylates, whidi minimize eliminations, s. J. P. Collman, S. R. Winter, and D. R. Clark, Am. Soc. 94, 1788 (1972). 

In addition, it has been shown that nucleophilic substitution reactions of mPEG-alk-oxides with ethyl 5-bromovalerate and ethyl 4-bromo-4-methyl butyrate, yield mPEG-ethyl valerate and mPEG-ethyl 2-methyl butyrate respectively, which upon hydrolysis should afford the corresponding free acids [81,82]. Presumably these reactions also give elimination products, as indicated for ethyl 3-bromopropionate. 

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