Cyclobutanone

[1191-95-3] C4H6O (MW 70.09) InChI = 1S/C4H6O/c5-4-2-1-3-4/h1-3H2 InChIKey = SHQSVMDWKBRBGB-UHFFFAOYSA-N (strained cyclic ketone capable of undergoing ring-expansion, ring-contraction and ring-opening reactions to give functionalized cyclopentanones,2 tetrahydrofurans,3 cyclopropanes, and terminally functionalized butyric acid derivatives1d) Physical Data: mp −51.1 to −52.5 °C; bp 97–100 °C; d 0.931 g cm−1; nD20 1.421. Solubility: slightly sol H2O; sol most organic solvents. Form Supplied in: colorless liquid, >99% pure, limited availability; relatively expensive. Preparative Methods: over 30 preparative methods have been reported. The most convenient methods include the ketene–diazomethane condensation4 and the selective di-Grignard reaction using 1,3-dibromopropane with carbon dioxide.5 Purification: distillation by spinning band column or preparative GC. Handling, Storage, and Precautions: flammable liquid (flash point 27 °C). Contact with skin and eyes should be avoided.