hi, so I have a problem in below, i’ve done some work but still confusing. do you guys think my approach is correct?

1. What happens to the HBr that forms here

2. How does the keto enol tauto occur like 3.what kind of reaction conditions are taken here?

3. The attack of acid directly on Br2(left side in image) is it reversible like i thought and the equilirium favors left side due to bond strengths like Br- Br bond is better than H -Br bond and O-H bond better than O-Br bond or the attack doesnt even happen due to kinetics

4. And there's another probability i thought of( right bottom) like why leaving Br- attacks the carbon in usual mechanism(the other attachment) why doesnt it take H with a 6-MCTS

5. If acid can attack the alpha bromo acid bromide in normal mechanism then why not directly attack acid bromide (left mid)

6. (Bottom)Why doesnt alpha bromo acid bromide attack more Br2. It is less nucleophilic because Br is withdrawing that's all?

For those who can‘t see, my answers were C, A B, A, A.

Hi everyone,

I'm trying to understand why I consistently obtain a low yield in the N-alkylation of a piperazine-containing compound using 1-azido-3-chloropropane.

I'm starting to suspect that the problem might arise in the preparation of 1-azido-3-chloropropane from 1-bromo-3-chloropropane with sodiumazide, rather than in the subsequent alkylation step.

Preparation of 1-azido-3-chloropropane

Following a literature procedure, I react 1-bromo-3-chloropropane with sodium azide using a 1:1 molar ratio. For the work-up, I extract the product with diethyl ether and carefully evaporate the solvent, keeping the temperature below 30 °C because the product may be volatile.

The main problem is that I cannot see anything useful on TLC, so I have no straightforward way to monitor the reaction. Consequently, I have been assuming that the desired azide forms successfully, but I have not independently confirmed this.

Subsequent piperazine alkylation

I then use the crude azide in the next step, reacting it with a compound containing a piperazine moiety.

After purification, mass spectrometry indicates that I have also formed a dialkylated product. Since I am aiming for selective monoalkylation, this is an unwanted side product. Given these observations, I suspect that something might be going wrong during the preparation of 1-azido-3-chloropropane, although I cannot rule out problems with the alkylation itself.

I also tried using triphenylphosphine followed by a ninhydrin test to check for the presence of the azide, but I did not obtain a useful result.

My questions are:

1. How can I verify whether 1-azido-3-chloropropane has formed successfully before proceeding to the next step?
2. Are there analytical techniques that would allow me to distinguish the desired azide from unreacted 1-bromo-3-chloropropane or other impurities?
3. Is there a way to assess the purity of the azide intermediate before using it in the piperazine alkylation?
4. Could residual starting material or impurities from the first step plausibly contribute to the formation of the dialkylated product, or is the latter more likely to result from the alkylation conditions themselves?

I would appreciate any suggestions for diagnosing the problem and identifying which step is responsible for the low overall yield.

Thanks in advance for your help!

I tried to do as much from memory as possible, especially searching out stuff I know was on the midterm. 3 and 4 are just me spitballing so I'm probably wrong!

I'm scared to start up the reactions portions, I need to brush up on those more.

Hi everyone,

I am stuck on this question. Can someone please guide me

How do I start? What mechanism steps do I use here? I don’t want the answer, I just need help with finding out how to start this.

I know that aldehyde has a -3 pka and hydronium has a -3 pka too so I’m not sure abt which would get deprotonated or if that’s even what I should do. Any hints help.

My class is in the middle of learning new rxn types like SN2 or nucleophilic attack etc but imm still lost.

Apart from hints, any advice on how to go about predict the product and mechanism problems? I know it’s a lot of memorization, but I’ve just been having a hard time identifying. Should I memorize?

Hi guys! I saw this a few minutes ago and I am not sure it's human made. The courses I receive from the professor are AI generated and I am suspecting this is too..

Noticed something that might be wrong with the bonds but I am not so sure with my chem knowledge 😅

Edit: Im a proud of myself for sniffing the AI and I thank everyone for confirming it! With the next occasion I will get, Ill bring this up in school!

I don’t think this is the correct explanation, but would the 1,4 product be the thermodynamic product as the Br’s are far away from each other and so steric bulk is reduced - making it more stable? I don’t really know how else to explain it otherwise, and i don’t really know how to explain which one has the more reactive intermediate either for kinetic product

I'm in first semester organic chemistry and thought I had a decent grasp of assigning priorities, but today in our pre exam review my professor assigned these priorities. The blue writing is how I assigned them and my reasoning, the red type is the answer key and how he wrote it in class.

When I asked him he said that the ring got priority unless the branch was a tert butyl. I tried to look it up and it seems like a ring follows standard rules for priority, and now I am more confused than ever lol. Does the ring get priority, and if so where is the cutoff where you would assign something else as a higher priority? For instance I assume a nitrogen would beat the carbon even with the ring? Thanks!

This is due tomorrow and I have no idea what I’m doing as we have just started learning mechanisms yesterday, is this looking correct?

In OCT's video, he says that the bromination of nitrobenzene would be the product circled in blue.

But since this is electrophilic substitution, would the reaction go through since it has a strong deactivator? I understand why it's meta but wouldn't the reaction not take place?

Hi, I am struggling with this mechanism in my orgo 2 class. I’m confused as to how the carboxylic acid is becoming the two R groups and what reagent(s) to use here. I’m also assuming here I don’t need anything to maintain the ketone since no oxidation will happen?

So from what I remember, simple distillation is between a volatile and non-volatile compound(purifying a mixture of liquids). Fractional distillation is about separating liquids that are both volatile. Steam distillation is for compounds with similar boiling points right? A vigreux column is used for steam distillation because the indents increase surface area right? So that even if the boiling points of the two liquids in the mixture are similar it can encourage boiling of the more volatile one first? Just asking for the purpose of clarity.

As you can read from the title, I am trying to make a stock solution of perfluoroeicosane but I am having trouble dissolving it. I’ve tried looking up what it dissolves in but I’m getting different answers between DMSO or using fluorinated solvents. I have tried using ethanol and stirring/heating it up a bit to try to make it dissolve, but no luck.

I want to vary To what extent does copper(II) ion concentration affect the rate of reaction between iron(III) nitrate and sodium thiosulfate, measured by the time taken for the purple colour to fade? but there are no studies done that prove varying the concentration of copper actually works but i need somthing that works

guys why is the (NH3) 2 and not 1 ?????

thanks everyone

If a solution can be provided it will be more helpful 😓

I have 2 examples. The top example with Br2 is 100% correct that is how my prof taught. I was told that the same product forms because the alkene product that would make the 1,4 is not the most substituted (the 1,2 product is).

But as I was going through my notes for the bottom example I found a contradiction. Does anyone know if the bottom example would follow the same rule because its 1,4 product is not the most substituted?

Also for the arrow mechanism for top example, does the BR attach first to the end of the diene (like how I drew it). Then the second bromine comes in and attached on the diene that’s in the middle (position 2). Because you are H or Br or whatever to the end to be able to do resonance.

Thanks.

This is the type of representation my teacher asks me, orbitals, and the π cloud of electrons for every atom, this is part of the Benzoic acid. And it's a pain in my arse

Learning on my own is currently a disaster. A lot of the class is struggling. I'm still scoring above average on exams somehow. (The average for the last exam was 43; it was mechanisms, IR, and NMR).

I have horrible foundational knowledge of SN1/SN2/E1/E2, which is probably why I'm struggling with this stuff.

How can I teach myself this material? What are the questions I should be asking myself?

The problems (in the pictures) on the psets are usually harder than the exams, so I tend to avoid them.

I'm trying to solve this exercise but I don't get the same value for the answer. I calculate both volumes using the PV=nRT and I get V1=0.87L and V2=2.16L, but when aplying the formula W=P*dV*101.325, I get 135J, and not 161J as the exercise does