--- title: "Gattermann reaction (formylation) Template | MolDraw" url: https://www.moldraw.com/templates/gattermann-reaction/ description: "Gattermann reaction (formylation) template: HCN is protonated (HCl/AlCl₃) to the electrophile HC≡NH⁺; benzene attacks it, loses H⁺ to give the aldimine, and…" 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/) › Gattermann reaction (formylation) [Name reactions](https://www.moldraw.com/templates/name-reactions/)Premium # Gattermann reaction (formylation) template ![Gattermann reaction (formylation) template: HCN is protonated (HCl/AlCl₃) to the electrophile HC≡NH⁺; benzene attacks it, loses H⁺ to give the aldimine, and hydrolysis gives benzaldehyde.](https://www.moldraw.com/templates/gattermann-reaction.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). HCN is protonated (HCl/AlCl₃) to the electrophile HC≡NH⁺; benzene attacks it, loses H⁺ to give the aldimine, and hydrolysis gives benzaldehyde. ## Mechanism step by step HCN, HCl and AlCl₃ put a CHO group on an aromatic ring (not the Cu/HX diazonium reaction, see points) 1. **Electrophile** – HCN takes H⁺ from HCl, helped by AlCl₃ 2. **Electrophilic attack** – The ring attacks carbon: an arenium ion 3. **Deprotonation** – Loss of H⁺ restores aromaticity: the aldimine 4. **Iminium ion** – Work-up in acid: N is protonated 5. **Water adds** – Water attacks the iminium carbon 6. **Proton transfer** – H⁺ moves from O to N (through the solvent) 7. **Loss of NH₃** – The O lone pair pushes out ammonia 8. **Deprotonation** – Benzaldehyde ## Key points - HCN and HCl first give formimidoyl chloride, HC(Cl)=NH; with AlCl₃ it gives the same HC≡NH⁺ electrophile. - Works for benzene, alkylbenzenes, phenols and phenol ethers. Zn(CN)₂ + HCl (Adams) avoids handling HCN gas. - NCERT also calls the replacement of N₂⁺ in a diazonium salt by Cl or Br with Cu powder and HCl/HBr the Gattermann reaction (ArN₂⁺Cl⁻ → ArCl + N₂). It is a copper version of the Sandmeyer reaction and usually gives lower yields. - Gattermann–Koch uses CO + HCl instead of HCN. Drawn with 161 atoms, 25 arrows, 11 shapes – every one editable in MolDraw. ## Sources - [Smith, March's Advanced Organic Chemistry, 8th ed., Wiley 2020](https://openlibrary.org/isbn/9781119371809) 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 Gattermann reaction (formylation) template free? You can preview the Gattermann reaction (formylation) 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 Gattermann reaction (formylation) 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 [**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. Every template can be opened and edited in MolDraw.