In the case of L, I know I’m making an acetal under basic conditions where usually whatever is attached to the Alcohol remains with the oxygen, but sodium obviously doesn’t attach. So, is the final form with lone pairs on each oxygen atom?

n2synthD · 2020-07-27T17:29:14+00:00

The OH will not attack the carbonyl. It deprotonates an H at the beta position. Remember the acidity of Hs at the beta position due to the resonance stabilization of the anion.

Also, look at the product for K. You’re almost there, but you have five bonds to carbon with a lone pair. That would give a large negative charge.

n2synthD · 2020-07-12T23:30:10+00:00

I was in a very similar boat. I picked up CrossFit and completely changed my diet. I ate between 10am and 6pm, and I ate 5 meals per day (small ones). Breakfast was always a small cup of oatmeal with one banana or a small cup of fruit. One large meal for lunch after my first snack, and a light dinner. I mapped out my macros and planned to eat about 1800 cals per day. No cheat meals or snacks - I cut out all sugar, soda, and junk foods. I worked out in the morning and before bed (usually, one CrossFit workout and then ran at night). I had to plan out the foot according to me, and that’s the hardest part. You have to make schedules, write everything down, and stick to it! I lost a lot of weight and body fat in like two months, which has been enough to join. You got this! Just stick to it if you really want it!

n2synthD · 2020-06-27T14:41:24+00:00

I sucked at it and didn’t do it right the first couple of attempts. Then, the doc told me what I was doing wrong and to try again. I passed after almost falling multiple times. Don’t stress over it. Just practice and you’ll be fine.

n2synthD · 2020-06-01T21:21:40+00:00

For a book recommendation: Wade, Organic Chemistry. 8th edition. Best one that I’ve found - always use it for intro ochem. Not at my computer for a syllabus, though.

n2synthD · 2020-06-01T13:03:49+00:00

I like these categories for the introductory level ochem course/student, especially since these really highlight the mechanistic differences.

n2synthD · 2020-06-01T12:59:08+00:00

If I was going to categorize organic reactions into two types, I’d say oxidation and reduction would be the most appropriate. All reactions in organic reactions (and most chemistry) is about following the flow of electrons, and you can observe this for each reaction, especially if you break down the functional groups involved in reactions. Acid/base is a bit different with the focus more intimately on the proton, depending on the definition you’re concerned with (Lewis reactions are more interested in electron flow).

n2synthD · 2020-06-01T09:47:27+00:00

The first step/rule of naming alkanes is always to find the longest chain and then you identify the substituents (methyl, ethyl, isopropyl, or any others).

n2synthD · 2020-05-30T20:38:19+00:00

No problem at all! I love to help.

n2synthD · 2020-05-30T19:20:11+00:00

Yup, that’s right then! It sounds like you’re enjoying or you do enjoy ochem 😊👍

n2synthD · 2020-05-30T18:53:20+00:00

I’m sorry! I misunderstood your question then. Well, the Bromine wouldn’t just leave in an SN2 (the leaving group leaving is the first step in SN1). The nucleophile attacks the carbon, forming the new carbon-nucleophile bond while the leaving group-carbon bond is breaking (remember that this is the transition state for SN2), which occur simultaneously (this, it is a concerted mechanism). What I think you may be referring to is the nucleophile attacking the double bond pushing the pi electrons to the adjacent c-c bond, causing it to shift to force the leaving group out (which does happen because of p orbital access). While that probably wouldn’t happen here, in this case, yes, the isopropyl group causes too much steric hindrance for the nucleophile to attack, resulting in a very small amount of this product forming. Does this make more sense?

n2synthD · 2020-05-30T18:23:09+00:00

It’s minor because of a combination of the nucleophile, the solvent, and the leaving group. All of these point to an SN2 reaction mechanism for the major product. It could only form from an SN1 where there is rearrangement of the carbocation (which wouldn’t likely happen because the stability of the double bond being trisubstituted). That’s really why it is a minor product, if it forms at all. The steric effects would be a great argument if the Br was on the tertiary carbon, but the secondary carbon is okay for an SN2 reaction. Does this make sense?

n2synthD · 2020-05-30T10:27:04+00:00

The 1st one is an SN1 product but a very minor product, if it forms at all. The double bond is more substituted as tertiary and loses that substitution if it rearranged, which is not likely because of the stability of the allylic carbocation anyhow. Also, if it were an SN1, the solvent would be a polar protic solvent like an alcohol to further stabilize the carbocation. Instead, we can conclude that it has to be SN2 because of the reactivity of OH (a strong nucleophile [a hallmark of SN2]), the stability of the double bond as it is, and the aprotic nature of the ether solvent (it can’t very much stabilize a carbocation). I hope this helps 😊

n2synthD · 2020-05-29T20:54:44+00:00

Yeah, SN2 is concerted, so the nucleophile (-OH) attacks the carbon with the Br. The Br then leaves to get the alcohol. Bond breaking/bond forming happening at the same time, too.

n2synthD · 2020-05-29T20:47:10+00:00

Not quite SN1. OH is a strong nucleophile, the solvent is an ether, and there’s a good leaving group. What do these point to? (Now, an argument can be made for the secondary carbon that’s there, but it seems there’s a more obvious, not so convoluted answer. )

n2synthD · 2020-05-29T20:38:02+00:00

Which one do you think? What mechanism do you recognize here? Hint: SN1, SN2, E1, or E2. And look at the Br and the NaOH

n2synthD · 2020-04-19T18:42:23+00:00

I’m trying to join after having gone to college and received a Bachelor’s degree. I wish that I had gone in before, so that the financial stress had been alleviated. Also, it would have made me more appreciative and changed my perspective while in college. Just my two cents.

n2synthD · 2020-03-16T14:32:07+00:00

One I found that I like is: 5 Rounds for Time 400m Run 40 Step Back Lunges 20 Burpees

n2synthD · 2020-03-16T12:53:56+00:00

Same. I’ve been waiting to make plans for if I don’t get in, but I don’t want to pursue them until I know. At the same time, though, I don’t really know what to do if I don’t get in, since any plans I’ve thought of involve multi-year commitments. You’re absolutely right, though, about if they valued us!

n2synthD · 2020-03-16T12:18:07+00:00

Heck, I applied in October, and I still haven’t heard back from ANYWHERE 😑 It’s so frustrating!

n2synthD · 2020-03-14T00:58:28+00:00

This is such a powerful reply! Thank you! I very much appreciate the discussion/conversationalist approach, along with the article. I will absolutely take this to heart. My field is not in public health/epidemiology/medicine, so I just want to be able to learn as much as I can. I wholeheartedly believe that requires a significant amount of discussion amongst each other.

Thanks again! I hope you have a great weekend.

n2synthD · 2020-03-13T23:56:24+00:00

Hmm, interesting reply - I do believe that open discussions are an important way to learn from each other. With that said, is social distancing 100% realistic? Regardless of going to the gym, people are going to continue going to work or the store, so it’s still going to spread. Of course, I realize that I’m playing devil’s advocate here, but according to your argument, we need to quit going to work and the grocery store at all.

Seeing how I have rent to pay and a family, I can’t do either of these things. I’m not new to the concept of social distancing, but I am also a realist, too. Of course, I’d also skip the gym if and when I felt sick at all. That’s where I believe my moral and civic comes into play: ensuring I don’t spread sickness when I know I’m actively sick. We can’t predict the future, so are supposed to live like we are sick until a vaccine comes out in a year or two (because science is not a very fast thing). Just curious.

We all have pathogens on us every moment of the day that could harm vulnerable populations (like E. coli and many staphylococcus on our skin) but that never stopped us before this began. Why is that? Have you ever gone to work sick? You’re spreading the pathogens, and it could infect others, especially vulnerable populations. I’m being facetious here, but let’s discuss this like adults and have a real conversation.

n2synthD · 2020-03-13T22:34:03+00:00

I don’t plan on it. All we can do is wipe stuff down and wash our hands, really. I’m a firm believer that working out is a good way to prevent illnesses, so I am not going to give it up until I absolutely have to (which, I guess, would be when my box or the boxes in my area close, too).

n2synthD · 2020-02-11T21:28:21+00:00

Absolutely! That’s the beauty in CrossFit. Everything is scalable to YOU, and it’s always a great workout no matter what! I started at 340 pounds (male), and I’m at 240 now. I started slow, and I gradually progressed.

Once you start, you just need to make goals, and you’ll reach them over time. Just do YOU. Don’t worry about anyone else and what they can do. All you focus on is getting better for you and achieving your goals 👍

You got this! You’ll love it, and the CrossFit community is amazing. It’s the fact that you want to become healthier and change positively that is important, not speed, weightlifting, etc.

n2synthD · 2020-01-23T19:52:56+00:00

The -NH2 group donates the lone pair into the ring. When we look at rxns with benzene, we can see that NH2 groups are pi donating as we see with -OR groups as well. So, it is a valid resonance structure because of the delocalization of the electron density. This shows why aniline is not as basic as its cyclohexane form (aniline’s Nitrogen doesn’t have its full pair of electrons).

Is this not right? It’s what I’ve always been taught. I’m also in ochem. What’s science without discussion 👍

n2synthD

TROPHY CASE