Here is a site you can read. It may not be the BEST but if you follow it carefully you will see how it's done.
http://www.masterorganicchemistry.com/2010/09/29/how-to-use-a-pka-table/
Basically, if the acid produces a WEAKER acid the reaction will proceed. If not, the reaction will not proceed. Here is the first one.
pKa = 37 for C6H6 (the acid product)
pka = 35 for C6H5CH3 (the acid reactant)
Since 35 is a stronger acid than 37 the reaction will proceed.
I'm assuming you know how to determine which is the acid and which is the base.
Indicate which of the metallation reactions given below would be thermodynamically favourable on the basis of the pKa data in non-aqueous media provided.
What is the underlying principle that determines whether the reaction occurs?
(a) C6H5Li + C6H5CH3 → C6H5CH2Li + C6H6
(b) LiCH2CH=CH2 + C6H5CH3 → C6H5CH2Li + CH3CH=CH2
(c) CH3Li + HC≡CH → HC≡CLi + CH4
(d) LiH + CH3CH=CH2 → LiCH2CH=CH2 + H2
(e) LiCH3 + CH3CH=CH2 → LiCH2CH=CH2 + CH4
Table pka values
HC≡CH 24
C6H6 37
CH4 48
C6H5CH3 35
H2 35
CH3CH=CH2 43
I don't understand anything in this question.. Can someone please give me a little help?
1 answer
1 answer