Grignard question

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predentgal

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I thought that if a grignard is in the presence of a compund with a hydrgen attached to it, then the the grignard will be destroyed because the grignard is such a strong base that it will extract the hydrogen rather than doing its normal job(adding to the carbonyl). That's why I chose A as the answer . Can anyone explain.Pleasee!!Thank youu:)

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If you have the following groups in a carbonyl compound:
-SH, -OH, -NH2, -NHR, - COOH, -C=CH, -SO3H, which all contain acidic protons
Will destroy the Grignard reagant.
It will not take any hydrogen out, just the acidic ones. I am not sure what the question is, so could you phrase it for us?
 
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Grignard can react as a strong base, as well as a good nucleophile.

For carbonyl carbon, which is deficent for electron, grignard will attack carbonyl carbon by nucleophilic mechanism; for other situation, eg water, Grignard will react as a strong base.

I feel that for OChem, sure there is always logic behind reactions, but you probably still need to memorize a couple of typical reactions, especially for test taking strategy.
 
What destroys the Grignard when it is destroyed??? Is it any acidic proton or the Alpha Carbon proton?? I dont recall seeing Grignard getting destroyed, only more so as nucleophilic addition.... DATlongshui, can you explain what occurs when Grignard reacts with water please, thanks.
 
first you have to remember that Grignard reagent always produce alcohol and what type of alcohol it will produce depends on what its reacting with. The Grignard Reaction is the addition of an organomagnesium halide (Grignard reagent) (which in this case is CH3CH2MgCl) to a ketone or aldehyde, to form a tertiary or secondary alcohol, respectively. if the acidic hydrogen is present then it will react with MgCl and destroy the grig reagent...so you have to keep gring away to make sure it reacts with aldehyde or ketone and then pull off MgCl with H2O to get alcohol.
 
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