[orgo814]

I am doing a problem and it has to do with FCH2OH. The problem requires you to draw a newman projection depicting the most stable conformation. Obviously, having an oxygen lone pair antiperiplanar to the C-F makes sense in terms of the nonbonding orbital donating into the low energy C-F antibonding orbital.

However, in the solution, the book compared sp2 oxygen to sp3 and drew the orbitals on the newman projection. With sp2, in the anti conformer, the F-C-O-H angle is 90 degrees and on the newman projection we have a p orbital with an sp2 hybrid orbital perpendicular to that p orbital with the hydrogen eclipsing another hydrogen. Why does the model look like this? Why would the hydrogen on the oxygen eclipse the hydrogen on the carbon in this model if we were "pretending" this was an sp2 oxygen.

Thanks for any clarification.

[Hunter2]

I dont understand it. For me are all atoms beside the hydrogen of course in sp3 hybrid.

[orgopete]

This virtually begs for more info. As I understand the 'solution', it is of a zwitterionic form of a protonated formaldehyde and a fluoride anion. If that is being predicted, that can explain the solution conformation. I'd be a little more circumspect on any conformations and their relative amounts. Just sayin'.