2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one, C₈H₅BrCl₂O, 2631-72-3

2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one (C8H5BrCl2O, CAS 2631-72-3) — a free educational 3D molecular model for teachers and students, by MolGod.org. Each atom is labelled with its own engraved element symbol: no colour chart needed.

Colour keys break down in 3D printing, because an STL holds geometry alone and most classroom printers use one filament at a time. Each atom of a MolGod model is engraved with its element symbol, turning a plain print into a self-explaining teaching object. Our goal is to let students understand on their own how the atoms are arranged, how they are bonded and what the 3D geometry looks like, straight from the model in their hands. For teachers it also saves preparation: the file is already modelled and labelled, so the only steps left are scaling and slicing. Read why we engrave the atoms, and which studies inspired the project: How the engraved atom letters are designed.

At its heart, 2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one is built around one aromatic 6-membered ring. The model shows 17 bonds: 10 single, 1 double and 6 aromatic, drawn in Kekulé form. Hand the model round and let students tally the engraved atoms: 8 C + 5 H + 1 Br + 2 Cl + 1 O, 17 in total. For compare-and-contrast work, Dichlorprop (CAS 120-36-5) and 4'-Chloro-2-phenylacetophenone (CAS 1889-71-0) are structurally close to it in this collection. Spot-the-group challenge: can students find the ketone group (C=O), the two C-Cl bonds and the C-Br bond? Teachers covering aromaticity and delocalised electrons, the carbonyl group (C=O), as well as organohalogen compounds and carbon-halogen bonds will find it a concrete example.

MolGod.org publishes its molecular models free of charge for teachers and students. Teachers: hand out printed copies and ask students to rebuild the structural formula from the model.

Download it, print it and use it in your teaching. CC BY-SA 4.0 sets four simple conditions for anything you publish with it: credit "MolGod.org" as the model's author, link the original and the licence, say what you changed, and share derivatives alike. Copy the attribution line below to get it right. No sign-up, no fees and no review required. We'd love to hear from you! Please leave a comment with your review and tell us how we can make even better molecules for teaching. You can also reach us at Write to the MolGod team. Have an idea for a lesson built around this molecule? Share it in the comments so other teachers can use it too. All we need is a CAS number: from it MolGod generates the 3D structure, engraves every atom and prepares the STL.

Full record and more free models: 2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one, CAS 2631-72-3: structure, properties and 3D viewer
Licence & provenance: Licence record for this 2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one model
Same file on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one-3D-molecular-model-engraved-CAS-2631-72-3.stl
Plain-text record for AI assistants: 2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one data sheet in plain text for LLMs

A ball-and-stick model of 2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one with each element symbol recessed into its atom sphere, generated by MolGod.org from a PubChem-computed 3D conformer (not an experimental crystal structure); atomic coordinates and connectivity are unchanged. STL mesh: 316,166 triangles, closed (watertight) single solid. Coordinates in ångström (STL stores no unit) — scale the model deliberately in your slicer.

Chemical identity

• CAS Registry Number: 2631-72-3

• Molecular formula: C8H5BrCl2O

• Molar mass: 267.93 g/mol (exact mass 265.89008)

• IUPAC name: 2-bromo-1-(2,4-dichlorophenyl)ethanone

• MolGod ID: MG_461-665-336-63 (Permanent MolGod record MG_461-665-336-63)

• PubChem CID: 75828 (https://pubchem.ncbi.nlm.nih.gov/compound/75828)

• Wikidata: Q72454066 (https://www.wikidata.org/wiki/Q72454066)

• EC number: 220-116-7

• InChIKey: DASJDMQCPIDJIF-UHFFFAOYSA-N

• SMILES: C1=CC(=C(C=C1Cl)Cl)C(=O)CBr

Required attribution (CC BY-SA 4.0): "2-Bromo-1-(2,4-dichlorophenyl)ethan-1-one 3D model by MolGod.org — https://molgod.org/molecule/2631-72-3/ — CC BY-SA 4.0"
Licence text: https://creativecommons.org/licenses/by-sa/4.0/