Problem 89 IR Spectrum (liquid film) 3410 4000 3000 2000...

Problem 89 IR Spectrum (liquid film) 3410 4000 3000 2000 1600 1200 800 v (cm?¹) Mass Spectrum 43 71 M?? = 86 (< 1%) No significant UV absorption above 220 nm C?H??O 40 80 120 160 200 240 280 m/e ¹³C NMR Spectrum (50.0 MHz, CDCl? solution) DEPT CH?? CH?? CH? proton decoupled solvent 200 160 120 80 40 0 ? (ppm) ¹H NMR Spectrum (200 MHz, CDCl? solution) expansion 6.0 5.5 5.0 ppm exchanges with D?O TMS 10 9 8 7 6 5 4 3 2 1 0 ? (ppm)

Transcript

00:01 In this problem, you're given different nmr, ir, and mass spec data, and you have the molecular formula c5h10o.

00:13 So the first thing that i want to do here is look at degrees of unsaturation.

00:21 So this will tell us the number of pie bonds and rings.

00:27 So we take the number of carbons and multiply by 2 and add 2.

00:33 Subtract the number of hydrogens and divide by two.

00:38 So here we get one.

00:40 So we either have one pie bond, so a double bond, or one ring.

00:46 If you look at your ir data, around 3 ,400, we have this broad peak.

00:56 So that's going to be an alcohol group.

01:02 And there you also have peaks that are right before 3 ,3 .3.

01:12 So that's for sp3 carbon hydrogen bonding and it's a little hard to see but right above 3 ,000 you have this little peak that's for an alken or sp2 carbon hydrogen bonding.

01:31 So we have a double bond between carbons here and that will be our one degree of unsaturation.

01:38 So so far we have a double bond between carbons and an alcohol.

01:45 So then if we look at our depth, here the peaks that go up are ch and ch3 groups.

01:57 So we have two of those, and one of them is around 35.

02:02 So that's usually going to be a methyl group.

02:12 Then we have a peak that goes down, and that's going to be our ch2 group, and that's around 110.

02:23 And then we have likely a ch group that's at 150.

02:40 And you'll notice in your regular carbon, you have a peak around 70, and that's going to be a quaternary carbon.

02:55 So that doesn't show up in depth because it doesn't have any hydrogens...

Question

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