--- title: "Swern oxidation Template – Chemistry Diagram | MolDraw" url: https://www.moldraw.com/templates/swern-oxidation/ description: "Swern oxidation template: DMSO and oxalyl chloride give the chlorosulfonium ion (with CO₂, CO and Cl⁻); the alcohol adds, Et₃N forms the ylide and a…" lang: en publisher: Scidart Academy generated: 2026-10-28 --- [MolDraw](https://www.moldraw.com/) › [Templates](https://www.moldraw.com/templates/) › [Name reactions](https://www.moldraw.com/templates/name-reactions/) › Swern oxidation [Name reactions](https://www.moldraw.com/templates/name-reactions/)Premium # Swern oxidation template ![Swern oxidation template: DMSO and oxalyl chloride give the chlorosulfonium ion (with CO₂, CO and Cl⁻); the alcohol adds, Et₃N forms the ylide and a five-membered elimination gives propanal and Me₂S.](https://www.moldraw.com/templates/swern-oxidation.webp) [Edit in MolDraw](https://www.moldraw.com/)Download with Pro Premium template. Preview and edit it free in MolDraw; downloading and exporting it is part of [MolDraw Pro](https://www.moldraw.com/pricing). DMSO and oxalyl chloride give the chlorosulfonium ion (with CO₂, CO and Cl⁻); the alcohol adds, Et₃N forms the ylide and a five-membered elimination gives propanal and Me₂S. ## Mechanism step by step DMSO activated by oxalyl chloride oxidises an alcohol to an aldehyde at −78 °C 1. **Activation** – DMSO oxygen attacks oxalyl chloride 2. **Chloride leaves** – C=O re-forms 3. **Chlorosulfonium ion** – Chloride attacks sulfur 4. **Fragmentation** – CO₂, CO and Cl⁻ are lost (gas evolution) 5. **Alcohol adds** – O attacks S; chloride leaves 6. **Deprotonation** – Et₃N removes the O–H proton 7. **Sulfur ylide** – A second deprotonation, at S–CH₃ 8. **Elimination** – Five-membered transition state: C=O forms, Me₂S leaves ## Key points - Primary alcohols stop at the aldehyde: no water, no over-oxidation. - Must be kept at −78 °C: the chlorosulfonium ion decomposes on warming. - By-products: CO (toxic), CO₂, Me₂S (strong smell) — work in a fume hood. - No chromium or heavy metals; secondary alcohols give ketones. Drawn with 172 atoms, 28 arrows, 12 shapes – every one editable in MolDraw. ## Sources - [Mancuso, Huang & Swern, J. Org. Chem. 1978, 43, 2480](https://doi.org/10.1021/jo00406a041) Original paper - [Omura & Swern, Tetrahedron 1978, 34, 1651](https://doi.org/10.1016/0040-4020(78)80197-5) Original paper - [Kürti & Czakó, Strategic Applications of Named Reactions in Organic Synthesis, Elsevier 2005](https://openlibrary.org/isbn/9780124297852) Textbook - [Clayden, Greeves & Warren, Organic Chemistry, 2nd ed., OUP 2012](https://openlibrary.org/isbn/9780199270293) Textbook ## How to use this template 1. Press **Edit in MolDraw**. The template opens on the canvas of the free MolDraw editor. 2. Change anything: move structures, edit atoms and labels, recolour highlights or delete what you do not need. 3. Add your own structures, arrows and text next to it, or combine several templates on one page. 4. Export the drawing as PNG, SVG or PDF for slides, worksheets, theses and papers. ## Frequently asked questions ### Is the Swern oxidation template free? You can preview the Swern oxidation template here and open and edit it in MolDraw for free. Downloading or exporting it is part of MolDraw Pro, together with the other premium templates. ### Can I edit the Swern oxidation template? Yes. It opens as an ordinary MolDraw drawing, so every structure, arrow, label and colour can be changed, and you can add your own content around it. ### Is the chemistry checked? Every structure is checked with RDKit and every curly arrow passes MolDraw’s electron-flow audit. The sources used are listed on this page. ### Which name reactions are included? Over seventy, covering the reactions most often asked in school-leaving exams (A-level, IB, CBSE, JEE and NEET) and first-year university courses, including condensations, rearrangements, oxidations, reductions and aromatic substitutions. ## More name reactions templates [**Fischer esterification**Free · Name reactions](https://www.moldraw.com/templates/fischer-esterification/)[**Grignard addition to a ketone**Free · Name reactions](https://www.moldraw.com/templates/grignard-addition/)[**Michael addition**Free · Name reactions](https://www.moldraw.com/templates/michael-addition/)[**Diels–Alder reaction**Premium · Name reactions](https://www.moldraw.com/templates/diels-alder/)[**Friedel–Crafts acylation**Premium · Name reactions](https://www.moldraw.com/templates/friedel-crafts-acylation/)[**Claisen condensation**Premium · Name reactions](https://www.moldraw.com/templates/claisen-condensation/)[**Friedel–Crafts alkylation**Premium · Name reactions](https://www.moldraw.com/templates/friedel-crafts-alkylation/)[**Cannizzaro reaction**Premium · Name reactions](https://www.moldraw.com/templates/cannizzaro-reaction/) ## Related pages [**Swern oxidation: reaction guide**Mechanism, conditions and exam notes](https://www.moldraw.com/reaction/swern-oxidation/)[**Curved Arrow Mechanism Worksheet**Free printable worksheet](https://www.moldraw.com/educational-materials/curved-arrow-mechanism-worksheet/)[**Predict the Product Worksheet: Organic Reactions**Free printable worksheet](https://www.moldraw.com/educational-materials/predict-the-product-worksheet/)[**All Name reactions templates**72 templates](https://www.moldraw.com/templates/name-reactions/)[**All chemistry templates**370 templates in 29 categories](https://www.moldraw.com/templates/) MolDraw Pro Download all 370 templates - Export the 291 premium templates as PNG, SVG or PDF - AI chemistry assistant - Structure scanning from images - Cloud save and teaching slides [See Pro plans](https://www.moldraw.com/pricing) Free templates stay free. 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