Thanks, deleted it.

The academic community wouldn’t likely find it that interesting, which is understandable. But given that the sum total of time spent yearly by sophomores trying to understand the SN2 reaction is at least several hundred man-years, J. Chem. Ed. would be a possibility. if I had my own lab, some time, and a few grand, I’d like to get to the bottom of it. Someday, hopefully, in my Alexander Shulgin-inspired dotage….

Yeah, that’d be an interesting paper to write up. Of course, who would publish such a work? J. Chem. Ed. would be the right place for it, methinks.

Also, to do it right, you’d need a fair bit of resources, like $500 for chemicals and an HPLC. Huh.

It is interesting how March explains Hofmann elimination in ‘typical’ cases like NMe3 or SMe3 leaving groups:

“The change to a positive(ly charged) leaving group causes the mechanism to shift toward the E1cB end of the spectur, where there is more C-H bond breaking, and where acidity is more important (and where CH3 hydrogens are more acidic than RCH2 hydrogens)
…
Thus the percentage of 1-ene obtained from CH3CH2CH2CHXCH3 was as follows (X listed in order of increasing size): Br-, 31%; I-, 30%; TsO-, 48%; SMe2, 87%; SO2Me, 89%; NMe3, 98%. (KOEt as base, http://dx.doi.org/10.1021/ja01591a049)

The data is there, but there are often odd little pieces missing, like solvents or counterions that are slightly different. It’s a patchwork quilt. I’d just like to see a study where all these experiments we talk about in the course are applied and the results are tabulated. Are you smokin’ what I’m rollin, Random Hand–Wavy Guy?

“Someone oughtta spend a few weeks putting together a good set of experimental results of this (and SN1/SN2!) for teaching purposes…. if we’re going to feed this to hundreds of thousands of introductory students per year, it would be nice to have the hard data set.”

SciFinder? Wouldn’t be too hard.

The ref you give to the full paper in JACS (1979) is also what C&S quote from. I’d be interested in when this first started making an appearance in introductory textbooks – I see KOtBu mentioned as a “bulky base” for non-Zaitsev eliminations in courses all over the country.
Someone oughtta spend a few weeks putting together a good set of experimental results of this (and SN1/SN2!) for teaching purposes…. if we’re going to feed this to hundreds of thousands of introductory students per year, it would be nice to have the hard data set.

I checked March. Doesn’t tell too much. It’s very vague on the issue.

If you check it out, it’s in the beginning of Ch17 (5th edition) in the Orientation of the Double Bond section after it outlines the basic elimination mechanisms (#4):

“In further experiments, a large series of bases of different kinds was shown to obey linear free energy relationships between basicity and percentage of Hofmann elimination…” (although the cited paper doesn’t test alkoxide bases… http://dx.doi.org/10.1021/jo01337a018)