Potassium iodoplatinate

Fig. 22 Scheme for type B reagent sequence (cf. the reagent sequence ninhydrin — iron(lll) chloride — Dragendorff — potassium iodoplatinate [6]). 

There are a number of reasons for this. For example, in many of the solvent systems which are used, compounds are often not completely resolved, as exemplified by the data presented in Table 5.2. Furthermore, neither potassium iodoplatinate or Dragendorff s reagent are specific to opiates. It is therefore necessary to employ a more definitive technique. 

J. Potassium iodoplatinate spray B Bi(N0373 - KI Reagent C uragendorff s Reagent D Thallium Iodide... 

A Potassium Iodoplatinate Reagent B Ultraviolet Light C Dragendorff Spray D Potassium Permanganate Spray E p-Dimethylaminobenzaldehyde Spray... 

Based on the isolation procedure followed, one can conclude with some degree of certainty whether an isolated compound is an alkaloid or not. Particularly acid/base extraction schemes result in rather specific extraction of alkaloids. Moreover, several reagents that react specifically with alkaloids have been described, e.g., Dragendorffs reagent, potassium iodoplatinate, Mayer s reagent. The first two reagents mentioned are also used as detection... 

Potassium iodoplatinate reagent The reagent prepared freshly by mixing 3 ml of 10% aq. hexachloroplatinic acid solution with 97 ml of water and 100 ml of 6% aqueous potassium iodide solution. 

Dibenzyl sulfide, disulfide, trisulfide, and tetrasulfide can be separated chromatographically on paper impregnated with 1-bromonaphthalene 80% acetic acid can serve as the mobile phase which is allowed to overrun overnight. Three to five microliters of a 5 —10% solution are applied on the paper. Detection is carried out with potassium iodoplatinate, giving light yellow spots of dibenzyl sulfide and yellow to brown-yellow spots of disulfides and polysulfides on a pink-red background. 

---