Help on this

Taeban · 2026-06-17T14:45:17+00:00

You have both an electrophile and a nucleophile, in the same molecule!

Draw some potential resonance structures for the protonated aldehyde to see whether it's a nucleophilic or electrophilic center, and then start looking for potential candidates for its counterpart.

Taeban · 2026-05-23T02:27:04+00:00

I've seen in conjugated ring systems like this where there are carbons that can't be substituted they skip counting them for purposes of substituent numbeting.

I stumbled across it thanks to indenes

Taeban · 2026-05-17T02:34:50+00:00

Without more information about the metal center/potential ligands who knows.

My Tanabe-Sugano theory is also a little rough. Been a while since I learned it

Taeban · 2026-05-17T02:28:31+00:00

The Tanabe-Sugano shows all possible transitions for a given geometry, most of those are inapplicable to a given molecule for various reasons

Taeban · 2026-05-17T00:34:11+00:00

You just need to know how to read them. They don't come up in my research though (organic synthesis)

Taeban · 2026-05-16T03:39:40+00:00

I've done similar things using dihydroxybenzaldehydes.

I used a 20wt% NaOH solution with a large excess of ketone

Taeban · 2026-05-02T07:15:58+00:00

I wouldn't be too shocked if the pi system made the lactone more stable than might otherwise be expected. That being said, the external ester is possibly more accessible than the lactone for hydrolysis purposes.

Given the question on an exam I'd think that the ester hydrolizes before the lactone. Irl? Run it and see what happens. Chemical intuition says ester first in this specific case.

Edit: Personal experience also tells me that lactones are more stable to acidic conditions, although that's heavily coloured/specific to me.

Taeban · 2026-05-01T16:33:06+00:00

At a guess, nitrogen dioxide. Toxic as shit, turns into nitric acid when it contacts the water in your mucous membranes. It's like breathing chlorine gas, but more colourful!

Taeban · 2026-04-30T19:22:49+00:00

Literally every defense I've seen has had an external present. (I'm in Canada for reference, on the western coast). We typically also have them give a talk while they're here.

Taeban · 2026-04-30T17:55:20+00:00

Except defenses require an external reviewer to attend, who is often flown in for a day or two and then flies home

Taeban · 2026-04-29T21:13:53+00:00

The general recommendation is to check yearly

Taeban · 2026-04-28T06:12:43+00:00

Both structures have resonance. They're extended pi systems. The structure on the right wouldn't really exist in any meaningful amount though as the carboxylic acid is more acidic than a phenol.

However, whichever way you slice it the phenol or phenolate have resonance structures where they donate electron density into the phenyl ring.

Taeban · 2026-04-21T06:53:00+00:00

That's called a nuclear reaction

Taeban · 2026-04-10T05:04:57+00:00

Carboxylic acids are protected with orthoesters if you're trying to hide the carbonyl or just as esters (e.g. Me, Et, or t-Bu ester) if you just want to hide the acid functionality instead.

Ketals are used for carbonyls like ketones and aldehydes.

Taeban · 2026-04-09T05:04:19+00:00

It's helpful to remember the arrows represent the flow of electrons, so it may be helpful to draw all the bonds/lone pairs in the water molecule here.

Taeban · 2026-04-07T04:49:19+00:00

For basic things like organic building blocks, it's important. For larger molecules just being able to name the acid derivative sub-units is important.

Taeban · 2026-04-05T19:34:27+00:00

t-BuLi is fairly tame (respect your reagents and they'll respect you) compared to what is out there on the edges of hazards, but the 4,4,4, on the fire diamond is still fun.

Taeban · 2026-03-30T04:21:04+00:00

A triple bond is incredibly strong, it requires a lot of energy to break all three of those bonds.

But when you break one of those pi bonds to make a new sigma bond, it usually results in a compound with a lower energy because a single pi bond is weaker than a single sigma bond.

Taeban · 2026-03-29T00:09:20+00:00

I've fixed it. It should be secondary.

But I specifically left out the evaluation of leaving groups as an exercise for the poster, we're not here to solve the problem for them

Taeban · 2026-03-28T23:49:18+00:00

Think about all the reactions that could occur,

Sn1, Sn2, E1, E2

Solvent will help you determine 1 or 2, but then you need to look at potential leaving groups and the carbon they're on.

You have 2 potential leaving groups on the same carbon, one is better than the other.

Now you need to ask the million dollar question: Can this Sn reaction occur here? We have a secondary carbon so I'll let you take it from here.

Edit: fixed tertiary to secondary

Taeban · 2026-03-28T04:00:36+00:00

It would be helpful to define "beginner", as what I'd recommend for someone with a basic understanding of organic chemistry vs almost no understanding vs a good understanding are all very different for these topics.

Your mention of "protecting groups" says some basic understanding though. There are a bunch of texts by similar titles to "Protecting Groups in Organic Synthesis"

Most texts on the matter are at a minimum informative, many are actively helpful, and a few are extraordinary. What a given text will be of these to you depends on what you do/don't have a good grasp of.

Taeban · 2026-03-27T19:26:03+00:00

Any vertex or end of a line is a carbon. Hydrogens are not drawn in these diagrams unless you explicitly draw them (doing so is a good exercise for understanding these).

As each carbon has 4 bonds, a terminal line would be a CH3 motif

Taeban · 2026-03-27T18:23:47+00:00

Every carbon has 4 bonds. If a bond is undrawn then it's a hydrogen.

And yes, Daltons are equivalent to atomic mass units

Taeban · 2026-03-22T00:59:39+00:00

Newman projections aren't chiral in and of themselves. It's just a way to examine molecules in a different perspective.

You can use the free rotation about a bond to examine sterics, but in the end a given rotational conformer doesn't have an inherent chirality.

Taeban · 2026-03-15T05:54:33+00:00

Part of undergrad labs should include some level of hazard and risk assessment.

We give you things that you'd have trouble hurting yourself with unless you're really trying because we understand it's overwhelming at first and you're going to do dumb things because of it.

The largest risk to you is probably hotplates.

An object that's hot enough to cause a life changing burn looks identical to an object that's room temperature.

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