Sodium perchlorate partitioning

Table 12 Results of SXLSQI Modeling of Sodium Perchlorate Partitioning...

I. 4-methoxyacetophenone (30 //moles) was added as an internal standard. The reaction was stopped after 2 hours by partitioning the mixture between methylene chloride and saturated sodium bicarbonate solution. The aqueous layer was twice extracted with methylene chloride and the extracts combined. The products were analyzed by GC after acetylation with excess 1 1 acetic anhydride/pyridine for 24 hours at room temperature. The oxidations of anisyl alcohol, in the presence of veratryl alcohol or 1,4-dimethoxybenzene, were performed as indicated in Table III and IV in 6 ml of phosphate buffer (pH 3.0). Other conditions were the same as for the oxidation of veratryl alcohol described above. TDCSPPFeCl remaining after the reaction was estimated from its Soret band absorption before and after the reaction. For the decolorization of Poly B-411 (IV) by TDCSPPFeCl and mCPBA, 25 //moles of mCPBA were added to 25 ml 0.05% Poly B-411 containing 0.01 //moles TDCSPPFeCl, 25 //moles of manganese sulfate and 1.5 mmoles of lactic acid buffered at pH 4.5. The decolorization of Poly B-411 was followed by the decrease in absorption at 596 nm. For the electrochemical decolorization of Poly B-411 in the presence of veratryl alcohol, a two-compartment cell was used. A glassy carbon plate was used as the anode, a platinum plate as the auxiliary electrode, and a silver wire as the reference electrode. The potential was controlled at 0.900 V. Poly B-411 (50 ml, 0.005%) in pH 3 buffer was added to the anode compartment and pH 3 buffer was added to the cathode compartment to the same level. The decolorization of Poly B-411 was followed by the change in absorbance at 596 nm and the simultaneous oxidation of veratryl alcohol was followed at 310 nm. The same electrochemical apparatus was used for the decolorization of Poly B-411 adsorbed onto filter paper. Tetrabutylammonium perchlorate (TBAP) was used as supporting electrolyte when methylene chloride was the solvent. 

Isolation of (I-l) and (I-m). a) 3,6,17-Triacetylnormorphine (I-l). Morphine N-oxide (10 mg) was heated at reflux temperature in 5 ml acetic anhydride- e for one hour. In the first several minutes of the reaction, the solution appeared exothermic with simultaneous color changes (yellow to red to light brown). The solution was then cooled to room temperature, and water (10 ml) was added. When the mixture became homogeneous, solid sodium carbonate was added to pH 9.0. The mixture was extracted with 3x125 ml portions of ether.The extracts were combined and evaporated to dryness. The ether extract was mixed till homogeneous with 8g celite, 10 ml 1% perchloric acid and 10 ml ether to comprise the top layer of a partition column (2.5 in. diam.). The bottom layer of the column consisted of a homogeneous mixture of celite (5 g) and 10 ml 1% perchloric acid. The column was eluted with 300 ml anhydrous ether. The ether eluate was evaporated to dryness. GC/MS analysis indicated the presence of (j[-i) (M at m/e 397). GC quantitation established its purity as 94.7%. Elution of the celite column with 300 ml water-washed chloroform followed. The chloroform eluate was evaporated to dryness and analyzed by GC/MS. The major constituent was heroin (M at m/e 369), as well as several other minor products, b) 3,6,17-Triacetyl-dQ normorphine (I-m). Morphine N-oxide (10 mg) was dissolved in 5 ml acetic anhydride- 0 and heated at reflux temperature for one hour. The reaction mixture was worked up by the procedure described above for 3,6,17-jriacetylnormorphine (1 -1). 3,6,17-Triacety 1-dq-nor-morphine (M at m/e 406) was obtained in the ether eluate from a 1% perchloric acid-celite column and was analyzed by GC/MS. T e major constituent from the chloroform eluate was heroin- 0 (M at m/e 375). 

As shown in Table 3.1.2, some authors have proposed adding different reagents to the mobile phase to reduce the peak tailing of some componnds, like for example acetic acid (AcOH) in the event of BZ3 (DiNunzio and Gadde, 1990), or ethylenediaminetetraacetic acid (EDTA) for BDM determination (Schakel et al, 2004). Salts, snch as citrate, phosphate and ammonium or sodium acetates, have often been nsed for bnffering purposes. On the other hand, different authors have proposed the use of voluminous ions like tetram-ethylammonium chloride (TMAC) and/or sodinm perchlorate (Gagliardi et al, 1986, 1987, 1989 De Orsi et al, 1995), or stearyltrimethylammonium chloride (STAC) (Ohba et al, 1991) to establish an ion-pair partition process. Moreover, the nse of cyclodextrines has helped to solve unresolved peaks, as performed by Chisvert et al (2001d) who employed hydroxypropyl-jS-cyclodextrine (HP-j -CD) as mobile-phase modifier. 

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