Name the intermediate involved in reimer tiemann reaction
Answers
Answer:
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The intermediates formed in the Reimer-Tiemann reaction.......
6 intermediates
- Chloroform to tricloromethide anion.
- Tricloromethide anion to dichlorocarbene.
- Phenol to Phenoxide
- Phenoxide to adduct
- adduct to (dichloromethyl)phenoxide
- dichloromethyl group into 2- formyl phenoxide
Explanation:
However, as an organic chemist I need to point out that there are at least 6 intermediates in this transformation (arguably more). To enumerate, under strongly basic conditions chloroform is deprotonated to form trichloromethide anion (#1) which then loses chloride to generate dichlorocarbene (#2). Likewise phenol is deprotonated to form phenoxide anion (#3). Phenoxide is crazy electron-rich and is attacked by electron-deficient CCl2 to form an adduct (#4) which then rearranges to 2-(dichloromethyl)phenoxide (#5). Finally the strong base hydrolyzes the dichloromethyl group to give 2-formylphenoxide (#6). (That hydrolysis likely involves another intermediate.) Not until we neutralize the #6 with acid do we recover the product aldehyde.
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It is a shame that the mechanism of this reaction is often glossed over in textbooks.
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