(S)-1-Bromo-1,2-diphenylethane reacts with the strong base CH3CH2ONA to produce the cis- stilbene and trans-stilbene as shown below: trans-Seilbene (major products cis-Stilbone (a) The reaction is stereoselective, and the major product is trans-stilbene. Explain why the trans-stilbene is the major isomer using Newman projections looking down the C1-C2 bond, that lead to formation of each product and compare their ground state conformation stability. (b) When (R)-1-Bromo-1,2-diphenylethane reacts with CH3CH2ONA the stereochemical outcome does not change, i.e., trans-stilbene is still the major product. Explain.

(S)-1-Bromo-1,2-diphenylethane reacts with the strong base CH3CH2ONA to produce the cis- stilbene and trans-stilbene as shown below: trans-Seilbene (major products cis-Stilbone (a) The reaction is stereoselective, and the major product is trans-stilbene. Explain why the trans-stilbene is the major isomer using Newman projections looking down the C1-C2 bond, that lead to formation of each product and compare their ground state conformation stability. (b) When (R)-1-Bromo-1,2-diphenylethane reacts with CH3CH2ONA the stereochemical outcome does not change, i.e., trans-stilbene is still the major product. Explain.

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter14: Elimination

Section: Chapter Questions

Problem 34E

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