Question: Compound 1 is observed to undergo debromination
Compound 1 is observed to undergo debromination upon treatment with DMF to afford an alkene. The E-isomer (compound 2) is obtained exclusively (none of the Z-isomer is observed). A concerted mechanism (shown below) has been refuted by the observation that diastereomers of 1 also afford the E-isomer exclusively when treated with DMF. 
a. Explain why the mechanism shown is inconsistent with this observation. b. Classify this reaction as stereoselective or stereospecific, and explain your choice.
Transcribed Image Text:
Br H. Br (DMF) 1 2
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