Syntesis of (1R,2S)-1-(m-Bromophenyl)-3-methyl-1,2-butanediol - Assignment Example

Synthesis of (1R,2S m-Bromophenyl)-3-methyl 2-butanediol Synthesis of (1R,2S m-Bromophenyl)-3-methyl 2-butanediol involves nine important steps.Step I:The reaction begins with the abstraction a chloride from 1-Chloro-3-methyl butane by the iron (III) chloride to from a carbanion. Since the Nitro-group is deactivated, the carbanion formed attacks the nitrobenzene at the meta-position (McMurry and Simanek 170).Step II:Step II involves allylic bromination of benzene. N-Bromosuccinimide (NBS) is the reagent used commonly for this type of bromination as it provides a low concentration of molecular bromine.

Each molecule of hydrogen bromide that is formed is converted into Br2 by NBS (Carey and Sunberg 371). Illumination of light facilitates the bromination process (Tabert 180).Step III:This step involves the abstraction of a bromide to form a double bond potassium tert-butyl which is a strong, non-nucleophilic base. Step IV:This step involves epoxidation of alkenes using a peroxy acid. The reaction is regioselective since the two new C-O σ bonds formation occur at the same time from the peroxy acid.

Step V:This step involves acidic hydration of the ether to form a diol. The hydrolysis process is a concerted one and stereospecific and forms anti diols (Wyatt and Warren 560)Step VI:This step involves bromination of the nitrobenzene. The aluminium bromide abstracts a bromide from bromine molecule, and the bromide ion formed then attacks the benzene on meta-position since nitro-groups are meta-directors (McMurry and Simanek 170).Step VII:In this step, the nitro-group is reduced to amino-group using tin metal in the presence of an acid.

Step XIII:In step xiii, sodium nitrate is used to remove the amino group from the benzene ring at a temperature between 0-10 0C.Step X:The step involves the formation of (1R,2S)-1-(m-Bromophenyl)-3-methyl-1,2-butanediol by reducing the product formed in step xiii using sodium borohydride.Works CitedCarey, A. Francis and Sundber J. Richard. Advanced Organic Chemistry. New York: Springer, 2007 Print.McMurry John and Simanek, E. Fundamentals of organic chemistry. Cengage Learning 2006 Print.Tabert F. Douglas. Organic Synthesis.

New York: Oxford University Press, 2011 Print.Wyatt Paula and Warren Stuart . Organic Synthesis: strategy and control. John Wiley & Sons, Inc., 2007 Print.