<p>I was kind of bummed he didn't have us compare fisher projections. But I though it went okay. I'm not going to celebrate/slit my wrists until thrusday so until then...</p>
<p>how'd you do?</p>
<p>fmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfmlfml</p>
<p>fffffffffffff-i didnt even get to problem 7. oh god-i dont want to see what i got.</p>
<p>yeah-there was no caluclations of %ee, or enough comparing stereoisomer relationships which felt like 90& of probelm set 8…</p>
<p>what was the leaving group on #7?</p>
<p>which one was #7?</p>
<p>if it was w/ the two nitrogen’s, I put the one on the left was the leaving group and they left from the hydrogen (b/c its conj Acids pKa was higher than the one w/ 2 i-pr and an a carbon chain). Then I put the (-) on the leaving group doing an Sn2 with the carbon that had a bromine. I dunno</p>
<p>Did you guys use resonance on the substitution of ethyl chloride when the nitrogen was being attached?
And for the CN- and s-adenosylmethonine rxn, did you remove each bond around the sulfur and make it R-CN and a neutral sulfur?
marinopyrrole has hindered rotation about the carbon - nitrogen bond called altropisomerism. Right?
Was the spiro molecule **with **substituents was Achiral meso?
Chloronation of ethane resulted in only one molecule?</p>
<p>i feel worse after asking these questions…:(
;(</p>
<p>Ouch- that question looks painful, anon. Haha</p>
<p>yeah i put the same things for marinopyrrole. for the spiro i said achiral-didnt say meso tho? yikes-im scared.</p>
<p>i put meso b/c i thought both carbons with methyls were SC’s</p>
<p>wait the spiro one didnt have any methyl groups attached though-it was a cyclopentane and cyclobutane right?</p>
<p>yeah…oh crap! I think I screwed up the chlorination of ethane, what did you guys do?</p>
<p>yeah i had a lot of trouble on the marinopyrrole one, probably because i never pay attention when he talks about molecule of the day. for the one above it, did it not have any stereocenters? and did you put any charges? I tried to put +2 on Sulfur, but it didn’t work out to 0, so I just added a lone pair.</p>
<p>and anon, i used resonance for the second mechanism one, and did the same for the last question.</p>
<p>for the third mechanism one, i didn’t really look at the pka. i did remember using bromine as the leaving group. does it make that much of a difference?</p>
<p>nah…no 2+ on sulfur…the oxygen gave up its negative charge to pi bond. If you look on the pdf he sent us, the oxygen has a negative charge on it and a single bond with sulfur. So there was no charge to put.</p>
<p><a href=“http://en.wikipedia.org/wiki/Omeprazole[/url]”>http://en.wikipedia.org/wiki/Omeprazole</a></p>
<p>ARGGGG…I DID MESS UP CHLORINATION…I PUT 1 CHLORINE ON EACH DAMN CARBON!!!</p>
<p>that was the easiest part of the whole god forsaken test…</p>
<p>i like how in his previous midterms the section for MOD’s was multiple choice/EASY AS *<strong><em>. then for this year he decided to make it HARD AS *</em></strong>KKKKKKKKK.</p>
<p>i know what the hell?</p>
<p>why is the fluorine thing a bad electrophile?</p>
<p>i found 3 reasons (i incorporated the third into my first answer) </p>
<p>1) its negative. electrophiles are supposed to act like lewis acids and be electron pair acceptors but the oxygen has a negative on it meaning that it will repulse the incoming nucleophile. Because it undergoes resonance, the negative charge is distributed over more of the molecule.</p>
<p>2) Beta branching. Because the reation was Sn2, the nucleophile would interact through backside attack, the beta carbon was double branched making it difficult for the nucleophile to come in. Along with the negative charge, reaction would not proceed (or be really slow).</p>
<p>what did you do for the chlorination? i can’t remember but for some reason I put 2 chlorines on the molecule, I put that there was only one enantiomer.</p>
<p>one motherf()cking week…last time it was only a 2 day wait…</p>
<p>no one else took the exam?</p>
<p>what did you guys and girls put down for chlorination?</p>
<p>there was supposed to be 2 chlorines on the molecule-he said the MF was C2Cl2H2…i drew 3 structures but looking back i think one of them was redundant- F U C K…</p>
<p>this is sad, but on the cyclohexanechair that was marked “trans” on midterm 1 (with the two ispropyl groups on c1 and c2) on nomenclature, what was the stereocenter configuration? i changed by anser when there was 30 secs left in the chair and by the time i could check if it was right-they called time so i couldnt change it-</p>
<p>LOL me too!!</p>
<p>it was like the last 5 min when the GSI’s were saying “you can’t leave” and I realized that if I made it a flat ring and looked at it, I would distinguish R/S better. I got 2S’s.</p>
<p>oh, and it was isobutly b/c the beta carbon had the two methyls on it</p>
<p>why is the standard deviation so high? i always fall just short of the standard deviation. does anyone know his grade distribution for A’s/B’s?</p>