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xtracx
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Hi. I was to plan and conduct the reduction of 4-t-butylcyclohexanone into 4-t-butylcyclohexanol using NaBH4 as reducing agent, MeOH as solvent, and NH4Cl.
My question is about the use of NH4Cl. How does it act as a quenching agent? I've figured out that it acts as a quenching agent by removing Hydride ions (NH-). But I'm not too sure if this is true. Furthermore, i am wondering why water/dilute HCl is less effective? I am not too sure if I'm right, but is it because H2O is a weak electrophile & hence cannot effectively quench NH- nucleophiles? But then the same cannot be said about HCl, as the H3O+ generated is a relatively stronger electrophile & then should be an effective quenching agent right?. A little confused about that. I can't seem to find any info on the net about such reagents and their use for quenching :(Secondly, how should experimental conditions be changed if i choose to use LiAlH4?
I understand that: 1. An inert atmosphere (Nitrogen) is needed. 2. Anhydrous conditions are necessary. 3. Oil/graphite bath & not water bath should be used. But should there be any other drastic change in procedure? (Currently i am using NaBH4 in a chilled water bath, which is gradually warmed to room temperature)Thanks for all your help.
Manraj Singh
Singapore
My question is about the use of NH4Cl. How does it act as a quenching agent? I've figured out that it acts as a quenching agent by removing Hydride ions (NH-). But I'm not too sure if this is true. Furthermore, i am wondering why water/dilute HCl is less effective? I am not too sure if I'm right, but is it because H2O is a weak electrophile & hence cannot effectively quench NH- nucleophiles? But then the same cannot be said about HCl, as the H3O+ generated is a relatively stronger electrophile & then should be an effective quenching agent right?. A little confused about that. I can't seem to find any info on the net about such reagents and their use for quenching :(Secondly, how should experimental conditions be changed if i choose to use LiAlH4?
I understand that: 1. An inert atmosphere (Nitrogen) is needed. 2. Anhydrous conditions are necessary. 3. Oil/graphite bath & not water bath should be used. But should there be any other drastic change in procedure? (Currently i am using NaBH4 in a chilled water bath, which is gradually warmed to room temperature)Thanks for all your help.
Manraj Singh
Singapore
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