8. Explain why the following deuterated 1-bromo-2-methylcyclohexane undergoes dehydrohalogenation by the E2 mechani...
2. (10 points) Explain why the following deuterated 1-bromo-2-methylcyclohexane undergoes dehydrohalogenation by the E2 mechanism to give only the indicated product. н н wCH3 Осн, CH3 wCHs wCH Br H H D H not observed observed
2. (10 points) Explain why the following deuterated 1-bromo-2-methylcyclohexane undergoes dehydrohalogenation by the Emechanism to give only the indicated product. observed not observed
11/8/19 The cis- and trans-isomers of 1-bromo-2-methylcyclohexane are shown below. One of these isomers undergoes E2 elimination 50 time faster than the other. Illustrate the E2 mechanism using the chair conformers to explain why one isomer is much faster and give the major product of each reaction. 1-BUOK 1-BOK Illustrate the Sw2 mechanism for the reaction below and show what has happened to the stereochemistry of the compound. NaCN acetone
Answer all Answer all 4. What is the structure of the compound that gives the IR and proton NMR spectra? Examine the H NMR of each structure as a review. Note the chemical shift for each proton 100 MHz proton NMR spectrum CDC13 solution 2270 IR Spectrum (liquid film) 1745 - 4000 3000 1200 800 TMS 2000 1600 fem') oppm) O HƏNCH:C=c-c-OCH; NEC-CH:-0-OCH:CH; o 1,6--OCH HC --CHÚC H:C-C-OCH:CH.CN H;CCH: -2-0-CH:CN 1. Compound, B, has the molecular formula C7H12. On catalytic...
(a) When cis-1-bromo-2-methylcyclohexane undergoes an E2 reaction, two products (cycloalkenes) are formed. What are these two cycloalkenes, and which would you expect to be the major product? Write conformational structures showing how each is formed. (b) When trans-1-bromo-2-methylcyclohexane reacts in an E2 reaction, only one cyclo- alkene is formed. What is this product? Write conformational structures showing why it is the only product.
Why are the halide ions the only nucleophiles that work well in acidic conditions? trans-1-bromo-2-methylcyclohexane reacts with KOH via the E2 mechanism to form an alkene. Draw the structure of the product.
b) When the following deuterated compound reacts under the same conditions, the rate of formation of the substitution product is unchanged, but the elimination rate is slowed by a factor of 7. Why is the elimination slowed, but substitution unchanged? D3C-CH-CD3 + KOH - D2C=CH-CD3 + D3C-CH-CD3 Br alcohol OH (20) 7. Which reaction of the following pairs will take place more rapidly? a) CH, CH, CH, Br + CH, OH — CH, CH, CH, Br + CH30 — b)...
4. Why does the reaction of trans-1-bromo-2-methylcyclohexane yield the non-Zaitsev elimination product 3-methylcyclohexene on treatment with a base? Draw structures in chair conformations to support your explanation. сн, сн, КОН Br
4. The reaction between cis-1-bromo-2-methylcyclohexane and ethoxide (a very strong base) results in an E2 reaction. (refer to Mechanism 9.8 in your textbook) a. Show the transition state for this reaction. CHE + CH, CH, CH, OH b. Show the formation of the product(s) from the transition state. c. Use the rule from part 3d, to determine the major and minor alkene products.
The compound below undergoes E2 elimination using LDA as a strong base, and there is only one observed product. Draw the observed product and the theoretically possible isomer that we don’t see. Draw the mechanism to produce both. Draw an energy coordinate diagram for this reaction including the two low energy conformations of the starting material (hint: chairs), the observed product, and the theoretically possible product. Make sure all relative energies are accurate (ground state and transition state). Explain why...