308 PRACTICAL ORGANIC CHEMISTRY of ethyl acetoacetate, stirring the mixture until a complete solu-tion is obtained. Now add this solution slowly to the sulphuric acid, so that the temperature of the mixture does not rise above 10°; then continue the stirring for 30 minutes. Pour the mixture on to crushed ice (about ioo g.), when the solid y-hydroxy-4-methyl-coumarin separates. Filter off the coumarin at the pump. For purification, first dissolve the coumarin in cold 10% aqueous sodium hydroxide solution and reprecipitate it by the addition of dilute hydrochloric acid, and then recrystallise it from ethanol or methylated spirit, using charcoal if necessary. Yield of the colourless crystals, 3'5~4'O g.; m.p. 188-190°. Alkyl Phosphites. The Interaction of Phosphorus Tri-chloride and Alcohols. Phosphorus trichloride reacts readily with three equivalents of an alcohol e.g,, ethanol, in the presence of a tertiary amine such as pyridine, dimethyl-aniline, or diethylaniline, to form triethyl phosphite and hydrogen chloride,
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.