Full structural breakdown on my Substack! (Link bio) 🔗

• 🍋 Flavor & Stability: The doublets near 2.8 ppm belong to Sodium Citrate, keeping the acidity in check.
• 🌊 The "Missing" Peak: The gap at 4.8 ppm is where the water signal was suppressed.
👇🧵

• ⚡ Caffeine: The "wake-up" signal stands sharp as a singlet at 7.77 ppm.
• 🍬 The Sweetener Trio: We can clearly distinguish Aspartame (aromatic ring at 7.2 ppm), Acesulfame K (5.55 ppm), and the Cyclamate "forest" (1.0–2.0 ppm).
👇🧵

What’s inside your Coke Zero? 🧪🥤
Ever wondered what a sugar-free drink looks like at the molecular level? This is a 600 MHz ¹H NMR spectrum of Coca-Cola Zero (Ukrainian edition).
Even without sugar, the chemistry is dense! Here’s the breakdown:
👇🧵
#nmr #nmrchat #dietcoke

When you see two J-values around 10 Hz for a cyclohexane-like ring, you know you're looking at an axial proton.

• 12.1 Hz: Geminal coupling (2J).
• 10.6 Hz & 9.7 Hz: Two strong axial-axial 3J couplings — the hallmark of an anti-periplanar relationship.
• 4.04 Hz: One smaller axial-equatorial 3J coupling.
This dddd pattern at 1.47 ppm provides a perfect "fingerprint" for stereochemical assignment. 👇🧵

NMRMultiplet
In saturated 6-membered rings, the position of a proton dictates the entire splitting pattern. Since this proton is axial, the coupling tree reveals a classic set of interactions:
🧵👇
#nmr #nmrchat #chemistry #organicchemistry

Combined, these two factors leave no doubt about the regioselectivity of the alkylation. Did the J values lead you to the right answer, or did you rely on the CH2 shift? Let’s discuss in the comments! 👇
#NMR #spectroscopy #chemistry #organicchemistry #regioselectivity #structureelucidation

As a secondary "double-check," we can look at the methylene (CH2) bridge:
• N-CH2 (Structure A) appears upfield at 4.87 ppm.
• O-CH2 (Example on Slide 2) shifts downfield to 5.35 ppm due to the stronger deshielding effect of the oxygen atom.🧵👇

In the N-benzyl-2-pyridone system (Structure A), the ortho-coupling constant is characteristically bigger, typically around 6.7–6.9 Hz. In contrast, O-alkylated analogs usually exhibit significantly lower J values for these positions (~5 Hz, see similar examples).🧵👇

The results are in! 🧪 The correct structure for this #NMRweekend challenge is A.
The most reliable way to distinguish between N-alkylated 2-pyridones and O-alkylated 2-alkoxypyridines lies in the coupling constants of the alpha-protons (H6).🧵👇

It’s #NMRweekend time! 🧲⁉️
Can you identify the correct structure based on the spectrum?
Drop your answer in the comments 👇. I’ll post the full explanation in a few days. 😉
#nmr #nmrchat #chemistry #quiz

Why supplement?
Creatine Monohydrate is the gold standard. It’s scientifically proven to boost explosive power, increase lean muscle mass through cell hydration, and even support cognitive function. 🧠

• Where to find it? Naturally in red meat and fish, though your body synthesizes about 1g/day in the liver and kidneys.
• How it works: It rapidly regenerates ATP (your body’s energy currency) during high-intensity bursts of activity.

The Spectral Profile:
The sharp signals you see at 3.80 ppm and 2.91 ppm are the unique “fingerprints” of creatine’s structure.
Fast Facts:
• What is it? An organic nitrogenous acid that acts as a primary energy buffer in our cells.

Creatine: From Molecule to Muscle 🧬💪
What you’re looking at is the “molecular ID card” of one of the most researched supplements in the world, captured via NMR spectroscopy.
🧵👇
#nmr #spectroscopy #sportsupplements #creatine

RT nmr_spectroscopy / Organic Chemistry ⌬🇺🇦 @nmrspectroscopy.bsky.social Our latest NMR Challenge is out 🥳 @EnamineLtd @AnalBioanalChem LINK: https://link.springer.com/article/10.1007/s00216-025-06224-0

RT nmr_spectroscopy / Organic Chemistry ⌬🇺🇦
@nmrspectroscopy.bsky.social Our latest NMR Challenge is out 🥳 @EnamineLtd @AnalBioanalChem

LINK: link.springer.com/article/10.1...

#NMRchat 🧲

Zoom-ins help uncover the fine structure of these crowded regions — a great example of the complexity of natural mixtures captured by NMR.

The region between 3.0–5.3 ppm is packed with signals from sugars like glucose and fructose.
You can also spot additional small molecules — amino acids, other organic acids, and possibly traces of aroma compounds — especially in the aliphatic region (0.5–2.5 ppm). 👇🧵

🍋 ¹H NMR of Lemon Juice
Freshly squeezed science!
This proton NMR spectrum of lemon juice reveals a rich mixture of natural metabolites. The intense multiplets around 2.6–2.8 ppm are from citric acid, the dominant organic acid in lemon.

#NMR #nmrchat #chemistry 👇🧵

My standard speed on this QNP-equipped Bruker is 100–150 routine ¹H spectra per hour (not ideal quality, of course — Z1 + Z2). Most folks don’t believe me 🤣

UPD ✅: The correct answer is C. The methyl group appears as a doublet, indicating coupling to a CH (eliminating structure A). The aldehyde signal is also a doublet with ³J = 1.5 Hz, indicating coupling to a CH (eliminating structure B).

It’s #NMRweekend ⁉️🧲 Write your answers in the comments section 👇. Note: This is an experimental spectrum. The explanation for the challenge will be published in a few days 😉.
#nmr #nmrchat #chemistry #organicchemistry #spectroscopy #quiz #nmrchallenge #nmrquiz

Oh. My. God.
#fluorine #spin #coupling #nmr #nmrchat

Spin coupling of fluorine to 4 chemically inequivalent Hydrogens

dddd )

Fluorine in bicyclic molecules looks mind blowing 🤯.
#nmr #nmrchat #chemistry #science