[leximancer]

Okay, I feel dumb asking this question.  I'm trying to write a lab report, and I need to figure out this reaction:

CH₃-CCl₂-CH₃ + H₂O --> ?

This seems like such a simple reaction, but for some reason, I can't find the information I need.  I've did net searches, searches on this forum, my old organic chemistry textbooks, and two semesters' notes, but I can't seem find information on secondary dihaloalkanes reacting with water.

This is actually for an inorganic lab report.  We're supposed to compare the above reaction with the polymerization of silicone from an analogous monomer:

                                                     CH₃
                                                     |
n CH₃-SiCl₂-CH₃  +  n H₂O --> [-Si-O-]_n + 2nHCl
                                                     |
                                                     CH₃

This leads me to believe that the former reaction, the one with the dichloropropane, is a polymerization reaction.  But that doesn't seem right at all!

I would appreciate some help.  Thanks.

[FeLiXe]

I would say that you get acetone
OH attacks and Cl has to leave, same thing again
removing water leads to the ketone

the difference to the silicone is the double bond rule: the most stable double bonds are between 2nd period elements. silicon is to big for a stable double bond, therefore it polymerizes.

notice that the oxidation numbers are the same.

[lavoisier]

This is a classical example of differential reactivity between carbon and silicon, related to the existence of d orbitals in Si as opposed to C.

In this specific case, I'm not sure that it is possible to hydrolyse 2,2-dichloropropane to acetone by simply mixing it with water. I guess you need some stronger nucleophile (OH- ?) and much more drastic conditions. Just to name an example, dichloromethane is used as a solvent to extract stuff from alkaline aqueous solutions.

And still, if your nucleophile is also a fairly good base, you may start wondering if no side reaction occurs, like deprotonation and elimination of Cl-, and all possible variations thereof...
I'm not saying that any of these things can or can't happen, just that one should consider all the possibilities and then look for the most probable, according to kinetics and thermodynamics.

This is to say, leximancer, that I don't think you should feel 'dumb' asking this question. First because there are no stupid questions, but only stupid answers. Second because sometimes these tests put things too simply, as if there were just one possible result. Chemistry is not mathematics, and even for seemingly trivial systems, predicting the actual reactivity can be quite difficult.

[Custos]

I agree. The reason you can't find anything about this reaction is that it is a "trick" question - the reaction between CH3-CCl2-CH3 and water gives.... nothing. Nothing will happen. The point is to contrast the reactivity of the dichlorosilyl analog.