COMPLIANCE INFO_COMPLIANCE INFO 1983-2007

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P-C-111C 4.5.5 Amines. 4.5.5. 1 Alkyl mono-amines. Acidify 50 ml . of the compound in a reparatory funnel to a pH of 2 with concentrated hydrochloric acid. Add 10 ml . benzene. Transfer the lower layer to another separatory funnel . Shake with 50 ml . ether and discard the ether layer. Alkalize with strong potassium hydroxide (about 10 normal) and extract with two 50-m1 . portions ethyl ether. Dry ether layer with anhydrous potassium carbonate for several hours and with potassium hydroxide pellets over night. Filter a portion of the ether through a fine fritted glass crucible. Using a glass tube with outlet reduced to about 1 mm. , pass hydrogen chloride gas dried with concentrated sulfuric acid through 20 ml . of the filtered ether extract for 30 seconds . For blanks, use 50 ml . of the comparison formula of 4.5. 19.2 with and without 0.5 ml . of butylamine and carry through all the steps of the test. Observe after 30 minutes. A precip- itate in the extract from the compound shall be taken as indicating the pres- ence of mono-amines other than ethanolamine type, cloudiness sha lI be disre- garded. Failure of the blank with butylamine to develop precipitate shows the drying to be unsatisfactory. 4.5.5.2 Other amines. Separate the amines by saturating 50 ml . of the com- pound with anhydrous potassium carbonate and shaking thoroughly until solid salt remains. Transfer the top layer to a glass stoppered Erlenmeyer flask. Add anhydrous potassium carbonate in 1/2-gram (g.) portions until free flow- ing granular potassium carbonate remains in excess . Weigh 0.3 to 0.4 g. of this clear dried material into a 125-m1 . glass-stoppered Erlenmeyer flask containing 25 ml . glacial acetic acid. Before titrating, add 25 ml . glacial acetic acid and enough solid methyl violet indicator to give a strong purple color. Titrate with 0. 1 N perchloric acid, made by dissolving 60 to 70 percent perchloric acid in glacial acetic acid and adding just enough acetic anhydride to combine with the water in the perchloric acid solution, as determined by calculation. Standardize the acid with potassium acid phtha- late. It is important to exclude water completely, as it will be titrated along with the amines. Acetic anhydride, in excess up to 5 percent of the amount calculated as being necessary, does no harm. Milli-equivalents per g. dried material = ml . perchloric acid X normality weight of dried material Milli-equivalents per g. dried material in excess of more than 2 percent of that found for the comparison formula of 4.5. 19.2 when tested and calculated similarly, shall be considered evidence of the presence of amines other than ethanolamine type. CAUTION: There appears to be no hazard under the conditions given in the above procedure. However, (1) do not heat solutions; and also (2) dispose of titrated samples promptly. 11