Chemical Forums

Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: jinclean on October 27, 2009, 06:33:13 AM

Title: Are the Sp3 orbital is a stronger base than the sp2 atom?
Post by: jinclean on October 27, 2009, 06:33:13 AM

In the C=0 bonds ,in my textbook .it says that the sp3 is more active to be protonized than the C-O bond .but why in the C=N is less basic than the C-N bond?

Title: Re: Are the Sp3 orbital is a stronger base than the sp2 atom?
Post by: Schrödinger on October 27, 2009, 03:10:53 PM

sp2 hybridized atoms are more electronegative than sp3 hybridized ones due to greater s-character. So, the sp2 atoms tend to keep the unshared pair of electrons to themselves rather than giving them away to an acid's proton.

Title: Re: Are the Sp3 orbital is a stronger base than the sp2 atom?
Post by: jinclean on October 28, 2009, 07:25:34 AM

Thack you for your reply,
but the C=O is more basic than the R-O-R',it is oppose to this conclusion   

Title: Re: Are the Sp3 orbital is a stronger base than the sp2 atom?
Post by: lancenti on October 28, 2009, 10:47:18 AM

You may want to also consider the lack of a resonance structure when an ether acts as a base as opposed to a carbonyl group acting as a base.

Then there's also steric hindrance to consider, since if the R-groups are so bulky that they protect the lone pairs.