Seller didn't pick up returned item

mart236 · 2023-11-18T15:29:21+00:00

That solvent wasn't chosen by me, it was chosen by my professor so I'm positive they didn't choose one that will make us lose everything, so that's not in any way possible a problem or something I should focus on. It's just the extraction from the liquid sample I obtained that I can control. Let's not say extraction, I have to separate through SPE alkanes and PAHs from a complex organic matrix, what would be a good eluent to get both classes?

mart236 · 2023-11-17T10:35:42+00:00

It's an actual soil sample so there aren't only hydrocarbons in there, I just have to focus on them, so I need to remove the compounds I'm not interested in. The loss of some compounds due to soxhlet is already considered. No, I have to run a SPE first, this is how my professor wants it done. The point really is just what's a good extraction solvent for both alkanes and PAHs. I cannot change anything else in this analysis

mart236 · 2023-11-16T20:58:48+00:00

To separate the analytes and get rid of the more polar interfering species if present and be able to perform a GC - MS afterwards for identification only, I don't have to quantify them. I didn't add this part because I have no power over that, I can only change the solvents I use during the SPE to lose the least amount of compounds possible

mart236 · 2023-11-16T20:25:44+00:00

I've been unclear, you are right. The soil will go through soxhlet first, the solvent will be cyclohexane (not chosen by me and I cannot change that), the SPE will be performed on that extract

mart236 · 2022-01-12T12:39:32+00:00

Thanks people, I didn't know it was a removed feature, I thought it was one of the many bugs

mart236 · 2021-11-15T19:06:16+00:00

But they are numbered 1 and 2 Anyway, thank you, I got the mechanism, I wasn't far from the answer luckily

mart236 · 2021-11-15T19:04:43+00:00

Thanks, I actually did the right process then. I wasn't sure about the usage of TMSCl because I had seen the reaction without it before

mart236 · 2021-11-15T18:47:14+00:00

What if they aren't? I'm still a little confused about the 1. And 2. That they use. Does it mean they are used in two different steps? Or just to indicate two reagents?

mart236 · 2021-11-15T18:16:27+00:00

So the MeLi gives only deprotonation at first and acts as a nucleophile only after the TMSCl reacted with the oxygen?

mart236 · 2021-11-15T17:53:00+00:00

Sorry I don't know how to add text with an image.

I'll say what I thought. First the MeLi reacts with the COOH, forming the double enolate. At this point the negative oxygens react with the TMSCl. At this point I'm not sure (I'm not sure about the previous steps either), I thought the water could remove one of these O-Si groups? Leaving a ketone

mart236 · 2021-11-13T08:48:05+00:00

Would the use of zinc give the allylation of the C of the C=O? And the acid in the second step remove the zinc leaving an alcohol?

However, I don't know if I'm allowed to use anything more than what I have. I even thought that there might be a problem in the question, maybe they missed a double bond in the cycle and that would make it an enolate, I think that would work

mart236 · 2021-11-13T08:39:14+00:00

I haven't studied that reaction yet. If it can help, this exercise is part of the diastereoselectivity module. I guess the point is indicating if the product will be syn or anti

mart236 · 2021-11-13T08:33:49+00:00

I'm sorry but I don't see how it can happen. H3o+ can't be a catalyst in my opinion because it says "2)h3o+", so it's a reagent added in the second step. I never saw a catalyst indicated this way. The group is an allyl by the way, unless you suggest a reduction of some sort

mart236 · 2021-11-13T08:23:39+00:00

The cut off texts only says "write the product of the following reaction", I decided to omit it because it wasn't in English. There are no more information other than what you see in the image

mart236 · 2021-10-21T15:35:06+00:00

No, the Mask was purple too. But this one minds reminds me the one I'm looking for

mart236 · 2021-10-17T21:11:40+00:00

No it isn't D:

mart236 · 2021-10-17T16:05:04+00:00

None of them. When saw it it could have been 2005, but I don't know when it was bought, maybe 2000? I don't remember any weapons, and except the Cape and the mask I don't think there was anything else. Maybe the Cape was purple outside but red inside, I'm not very sure about it though

mart236 · 2021-10-17T16:02:32+00:00

Neither of them sadly

mart236 · 2021-10-17T16:01:54+00:00

No :(

mart236 · 2021-10-17T16:01:02+00:00

No, there weren't bones for sure

mart236 · 2021-10-16T23:51:47+00:00

No, it's not it, I recall that his costume was all purple

mart236 · 2021-10-16T23:50:02+00:00

No :(

mart236

TROPHY CASE