Cyclopentanones sieves

Other variations of condensation agents (ethanolic hydrochloric acid, ZnCI2 in THF, Triton B in dioxane, using AIC1, TiCl4, or molecular sieves) to promote the reaction of cyclopentanone and diethyl aminomethylenemalonate (13) were unsuccessful (75JHC1245). 

Cyclopentanone [120-92-3] M 84.1, b 130-130.5°, d 0.947, n 1.4370, n2s 1.4340. Shaken with aq KMnC>4 to remove materials absorbing around 230 to 240nm. Dried with Linde type 13X molecular sieves and fractionally distd. Has also been purified by conversion to the NaHS03 adduct which, after crystallising four times from EtOH/water (4 1), was decomposed by adding to an equal weight of Na2C03 in hot H2O. The free cyclopentanone was steam distd from the soln. The distillate was saturated with NaCl and... 

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