[nj_bartel]

Well I didn't actually run the GC - it's my professor's spectra.

 http://bama.ua.edu/~cschiel/CH237Sp2009/Exp3GC.pdf

Am I misinterpreting something or is there significant quantity of 1-methylcyclohexene arising from the dehydration of 4-methylcylclohexanol?

[azmanam]

given enough heat and acid and time, might the initial dehydration product undergo further reaction?  If so, when will it stop further reacting?

[nj_bartel]

Epiphany 

Does it seem odd to you that such large quantities of it appeared though (I'll supply the reaction details)?  We're seeking to determine the presence of the Evelyn Effect in the dehydrations of rac-2-methylcyclohexanol and rac-4-methylcyclohexanol.  For the rest of this, I'm just going to talk of the 4-methylcyclohexanol.  The 4-methylcyclohexanol was added to a roundbottom with 85% phosphoric acid with boil chips.  The roundbottom was set up for simple distillation, and heated to the point where the alkene and water products would boil and condense off, but not the unreacted cyclohexanol or phosphoric acid.  The first sample was about the first half of product, and the second sample was the second half of product. 

While it makes sense that the concentration of the 1-methylcyclohexene product would increase in the second sample, it doesn't seem like it should be so high to me.  It would require at minimum 2 rehydrations, 2 dehydrations, and a hydride shift, and that's assuming everything occurs in the proper regio-position (all occuring in sub-ideal conditions for direct hydration in the first place, and competing with the short time the alkene has before it boils off).  Do the results seem plausible to you?

[azmanam]

17% and 14% (if I'm interpreting the 2nd trial results right)?  sounds ok to me.

I'm not sure where the hydride shift happens.  There's no Markovnikov's rule to worry about here, so first rehydration give 3-methylcyclohexanol, then dehydration to 3-methylcyclohexene.  Rehydration to 2-methylcyclohexanol and dehydration to 1-methylcyclohexene.

[nj_bartel]

Had planned it out wrong in my head - you're right.  Thanks for your input, helped a bunch.