--- title: "Nazarov cyclisation Template – Chemistry Diagram | MolDraw" url: https://www.moldraw.com/templates/pericyclic-nazarov/ description: "Nazarov cyclisation template: (2E,5E)-Hepta-2,5-dien-4-one is protonated to a pentadienyl cation, which closes conrotatory to a trans-dimethyl oxyallyl…" lang: en publisher: Scidart Academy generated: 2026-11-13 --- [MolDraw](https://www.moldraw.com/) › [Templates](https://www.moldraw.com/templates/) › [Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-reactions/) › Nazarov cyclisation [Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-reactions/)Premium # Nazarov cyclisation template ![Nazarov cyclisation template: (2E,5E)-Hepta-2,5-dien-4-one is protonated to a pentadienyl cation, which closes conrotatory to a trans-dimethyl oxyallyl cation; loss of a proton and tautomerisation give 3,4-dimethylcyclopent-2-en-1-one.](https://www.moldraw.com/templates/pericyclic-nazarov.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). (2E,5E)-Hepta-2,5-dien-4-one is protonated to a pentadienyl cation, which closes conrotatory to a trans-dimethyl oxyallyl cation; loss of a proton and tautomerisation give 3,4-dimethylcyclopent-2-en-1-one. ## Mechanism step by step A protonated divinyl ketone closes by 4π conrotatory electrocyclisation to a cyclopentenone 1. **Activation** – Acid (or a Lewis acid) on the C=O oxygen gives a pentadienyl cation 2. **4π Electrocyclisation** – Four π electrons, thermal: conrotatory, so the two methyls end up trans (accepted mechanism) 3. **Elimination** – Water removes a proton next to the oxyallyl cation (drawn with + on the other allyl terminus): a cyclopentadienol 4. **Tautomerisation** – The enol turns into the ketone (acid catalysed): the conjugated cyclopentenone ## Key points - Woodward–Hoffmann: a pentadienyl cation has 4 π electrons, so the thermal ring closure is conrotatory (the photochemical one disrotatory). - (E,E)-Substituents at the termini end up trans in the oxyallyl cation; the elimination step can erase one of the two new stereocentres. - Strong Brønsted or Lewis acids (H₂SO₄, H₃PO₄, BF₃·OEt₂, FeCl₃, SnCl₄) promote it; the C=C usually ends up in the more substituted position. - Silicon-directed (Denmark) and catalytic asymmetric variants control where the double bond and stereocentres end up. Drawn with 86 atoms, 12 arrows, 6 shapes – every one editable in MolDraw. ## Sources - [Clayden, Greeves & Warren, Organic Chemistry, 2nd ed., OUP 2012, ch. 35](https://openlibrary.org/isbn/9780199270293) Textbook - [Fleming, Molecular Orbitals and Organic Chemical Reactions, Wiley 2010](https://openlibrary.org/isbn/9780470746585) Textbook - [Kürti & Czakó, Strategic Applications of Named Reactions in Organic Synthesis, Elsevier 2005](https://openlibrary.org/isbn/9780124297852) 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 Nazarov cyclisation template free? You can preview the Nazarov cyclisation 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 Nazarov cyclisation 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. ### Do the pericyclic templates show orbital symmetry? They show the curly arrows, the stereochemical outcome and the Woodward–Hoffmann rule that predicts it (conrotatory or disrotatory, endo or exo). ## More pericyclic reactions templates [**Diels–Alder reaction: the endo rule**Free · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-diels-alder-endo/)[**Diels–Alder regiochemistry**Free · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-diels-alder-regio/)[**Cope and oxy-Cope rearrangements**Free · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-cope-oxy-cope/)[**Claisen rearrangement**Premium · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-claisen/)[**Electrocyclic ring closure**Premium · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-electrocyclic/)[**1,3-Dipolar cycloaddition**Premium · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-dipolar-cycloaddition/)[**[1,5]-Sigmatropic hydrogen shift**Premium · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-15-hydrogen-shift/)[**Ene reaction (Alder ene)**Premium · Pericyclic reactions](https://www.moldraw.com/templates/pericyclic-ene-reaction/) ## Related pages [**Curved Arrow Mechanism Worksheet**Free printable worksheet](https://www.moldraw.com/educational-materials/curved-arrow-mechanism-worksheet/)[**All Pericyclic reactions templates**11 templates](https://www.moldraw.com/templates/pericyclic-reactions/)[**All chemistry templates**525 templates in 31 categories](https://www.moldraw.com/templates/) MolDraw Pro Download all 525 templates - Export the 437 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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