Re: Re: Neucleophiles

Hi Friends,
 
Better refer Lewis Acid base theory, All Lewis base are nucleophile.
 
Regards,
 
Rajesh

--- On Wed, 3/30/11, Lance C <[email protected]> wrote:


From: Lance C <[email protected]>
Subject: [The Chemistry Cluster] Re: Neucleophiles
To: [email protected]
Date: Wednesday, March 30, 2011, 11:56 PM


  



This is really going to make a mess of things. 
Would ammonia be a base or a neucleophile? 
When it is mixed with water, it forms a strong base NH4OH. You can either say it takes the hydrogen from water to form NH4+ and OH-, or it displaces H+ to form NH3OH-, which then picks up the hydrogen.

Lance

--- In [email protected], Nishana Ramsawak <nishanas9@...> wrote:
>
> Base attacks at more acidic protons while neucleophiles attacks at electron deficient carbon. Base is a specie that donates an electron pair or extracts a proton from othermolecule. A neucleophile is a specie that attack on positive or electron deficient site. Both base and neucleophile have excess of electrons.They may be negatively charged,neutral or partial negative portion of a polar molecule. The main difference between themis that a base extract H from other molecule and neucleophile attaches to the moleculeitself. It should be moved that a strong neucleophile is a weak base and vice versa.e.g. Chloride is a strong neucleophile due to its small size and electronegative nature butit is a weak base because it does not give electron pair easily (outermost electrons aretightly bound due to small size). Similarly, Iodide is a strong base but weak neucleophile due to large size.
> A nucleophile is a species that shares a pair of electrons with another atom to form a
> new covalent bond; a Lewis base. (Defining "nucleophile" as an electron pair donor is
> not enough. A nucleophile has electron density readily available to share (usually lone pairs or pi
> bonds), or at least have some incentive to share electron density (partial or full
> negative charge).
> Hope this helps!!! Nish.
> 
> --- On Sun, 3/27/11, Chaitanya Hari <chaitanyahari@...> wrote:
> 
> From: Chaitanya Hari <chaitanyahari@...>
> Subject: [The Chemistry Cluster] Re: InterContinental University
> To: [email protected]
> Date: Sunday, March 27, 2011, 1:31 AM
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> Hello  chemistry,
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>                              Plese explain the difference between a base and a nucleophile.
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