Question

Experiment 4: Synthesis of a tertiary alkyl halide Page 5 of 6

Experiment 4: Synthesis of a tertiary alkyl halide Page 5 of 6 Assuming that all other experimental conditions are the same; explain if an S,1 reaction would still occur if the following changes were made. If an Sk1 reaction would still occur: then state the IUPAC name and draw the structure of the product formed compare the rate of reaction to the rate of the original reaction (in this experiment), meaning would the reaction occur more slowly, or more rapidly? If an SN1 does not occur: state the type of reaction that would occur and draw the major product(s) that would be formed. We replaced 2-methyl-2-butanol with 2-butanol. [1 Mark] We replaced 12.0M HCl with 18.0M H2SO4. [1 Mark We replaced 2-methyl-2-butanol with 2-phenyl-2-butanol. [1 Mark]

Answer 1

solution: Хон 2-methyl-2-butanol synthesis: 12 MH O 01. 3 carbocution. 2-chloro-2-methyl- butune In this reaction formation of 3o curbocation and it is more. stable because tI and sleight) hyperconjugation effect of hydrogen atom. The order of stability of carbocation OH 2-butanol synthesis: ФОН OH 12 MHY 2 carbocation (2-chloro-1. butane)

This is SNV reaction. Thus 2-methyl 32-methyl-2-butanol under goes SNT reaction taster an a-butanol because of curbocation stability 18 M H₂S04 the carbocation will # If 12 m Hd replaced by by 18 M H2Sou the orm but Hcl is stronger acid than H2S04. Thus dissociation a ester than H₂SO4. Hence in 12mHc carbo carbocution formation is faster than 18 M Hason. 18 M Hasou. But But formation of formation of alkyl halide lise source of hy halogen. In hed the source of halogen is chlorine but in H₂504 no source of halogen. . In 18m H₂SO4 Only carbocation will form but no n source of halogen. No formation of tertiary alkyl halide. ph LOH OH 2-methyl-2-butanol 2-phenyl-2-butanol The rate of sNt reaction is faster in 2-methyl-2-butanol thun 2-phenyl-2-butanol because because in 2-methyl-2-butanol in am & 3° carbocation o is stabilised by t I effect and eight (8) hydrogen hyper- WH conjugative effect. While in a-phenyl-2-butanol, so carbocution ihr CH₂ o is stabilised by t I, tR and fire (s) hyperconjugative effect. But hyperconjugative than resonance (+2) effect. effect is stronger