264 PRACTICAL ORGANIC CHEMISTRY Reagent B is valuable for use with aldehydes or ketones which are insoluble in water, and therefore unsuitable for treatment with Reagent A (cf. benzaldehyde, p. 342; benzophenone, p. 346). It is much more concentrated than A, and consequently can be more readily used for the isolation and purification of the required hydrazone. Use. If the substance under investigation is soluble in water, dissolve about 0*1 g. in 1-2 ml. of water, and add 5-10 ml. of Reagent A. On shaking for a few minutes, with scratching if necessary, the yellowish-orange hydrazone will usually separate: if this does not occur, warm the solution gently in a hot water-bath for 5-10 minutes. If the substance under investigation is insoluble in water, dissolve about OT g. in a minimum of methanol or ethanol, with heating if necessary, and then add 0-5-1 ml. of Reagent B: then proceed as above. Precautions,
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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.