Part A For each reaction above, indicate which starting material is: (1) the nucleophile, (2) the electrophilic substrate, and (3) whether the reaction condition is best described as acidic, basic, or neutral. 1A. Optically pure (S)-3-bromo-3-methylhexane is treated with water and a substitution reaction forms an alcohol. Write the structure of the alcohol and describe the stereochemistry of the product. BrCH3H2OH3C OHelectrophilic substratenucleophile+ HBr These are “stealth” acidic conditions since HBr is generated as the reaction side-product. A racemic mixture (R and S) of the alcohol product is obtained because the reaction occurred via an SN1 mechanism. 1B. (S)-2-chlorobutane is allowed to react with NaI in a polar aprotic solvent, to yield a substitution product. Write the structure of the product and describe the stereochemistry of the product. ClHNaIpolar aprotic solvent such as acetoneS- configurationHIR- configuration only Because the reaction proceeded via an SN2 mechanism, there was complete inversion of configuration and the product will be 100% (R)-2-butanol. These are essentially neutral conditions; I- is the nucleophile and the electrophilic substrate is (S)-2-chlorobutane. 1C. Use the curved arrow formalism and equations to describe the mechanism for the reaction of ethyl bromide with potassium cyanide in acetone solution.This reaction occurs under basic conditions. –CN is the nucleophile while ethyl bromide is the electrophilic substrate. Part B: Complete the reactions by drawing structures of major products. Indicate important minor products. If no reaction occurs, write NR after the arrow. (minor product)primary alkyl center, good nucleophile/good base; SN2 dominatesH3CH2CCH2H2COCH3+secondary alkyl center, good base/nucleophile, protic solvent; E2 dominates but significant SN2 reaction expectedOH+major secondary alkyl center, good base/nucleophile, protic solvent; E2 dominates.Note: the alkoxide (RO-) aill be generated under these conditions, and RO- is less nucleophilic than
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