Sight down the C-2—C-3 bond, and draw Newman projection formulas for the
(a) Most stable conformation of 2,2-dimethylbutane
So, let's go ahead and come up with a Newman projection for 2,2-dimethyl butane, okay? So we know that we've got butane, so we've got a 4 carbon chain. So, let's just go ahead and draw it out like that and we also know that we've got 2 methyl groups on the number two carbon, right? So if we go ahead and start counting from the left or from the right we can go ahead and end up with the same thing, right? Since we know this molecule is symmetrical, so I'm just going to go ahead and add my 2 methyl groups there and for clarity thing I'm going to go ahead and add wedge and dash information even though it's not necessary here, since we don't have a chiral Center, okay? So we're going to be looking from carbons 2 and 3 like this, from this direction, okay? So, here's my eyeball looking down this bond, so I'm going to go ahead and draw our Newman projection, our front carbon should be the Y, right? since we've got our wedge and dash information here and our planar compound our planar substituent going directly down, right? So that's exactly what we have here and then on the back carbon we've got just recovered planar substituent going up, right? So we can go ahead and draw it like that and that means that we've got this, right? Kind of like a peace sign. So, looking here we know these are 2 methyl groups on our front carbon, right?? Well, we've got 3-methyl groups total, so we've got CH3 on the left CH3 on the dash, I'm sorry, in the right, which would give us the wedge here, right? And then we've got our CH3 down here. Now, on the back carbon we've got this over here, right? So that's going to be our CH3 and then you have just got our hydrogens, so I'm going to go ahead and highlight this, right? this is going to be our front carbon and this is our back carbon, so this whole thing back here, I'm trying not to bleed green everywhere, but so much of that, so guys, this is going to be our back carbon right here with our green, which just has our methyl and our two hydrogens and then this is going to be our front carbon with the yellow, that's going to have 3-methyl groups and guys that is actually our Newman projection for 2,2-dimethyl butane looking down carbon, looking down between the bonds of 2 and 3. Alright so, let me know give any questions, if not, let's move on.