Identification
B:
Dissolve about 250 mg in 5 mL of water in a test tube, cool in an ice bath, add 5 mL of trinitrophenol TS, and scratch the inner surface of the tube with a glass rod to induce crystallization. Collect the precipitate on a filter, wash with cold water, and dry at 105
for 1 hour: the picrate so obtained melts between 184
and 189
, when tested by the method for
Class I (see
Melting Range or Temperature 741).
[CautionPicrates may explode.
]
C:
To a solution of 100 mg in 2 mL of water add a few drops of 2 N nitric acid and 1 mL of
silver nitrate TS: a yellowish white precipitate is formed.
Related compounds
Adsorbent:
0.25-mm layer of chromatographic silica gel mixture.
Developing solvent system:
a mixture of acetone, methanol, water, and hydrochloric acid (70:20:5:5).
Chromatographic plates
Predevelop suitable thin-layer chromatographic plates (see
Thin-Layer Chromatography under
Chromatography 621) by placing in a chromatographic chamber saturated with
Developing solvent system, and allow the
Developing solvent system to move about 15 cm. Remove the plates from the chamber, dry at 105
for 15 minutes, and cool.
Test solution
Dissolve 100 mg of Clidinium Bromide in 1.0 mL of 0.1 N methanolic hydrochloric acid.
Application volume:
20 µL.
Spray reagent
Dissolve 850 mg of bismuth subnitrate in a mixture of 10 mL of glacial acetic acid and 40 mL of water. In a separate container, dissolve 20 g of potassium iodide in 50 mL of water. Mix the two solutions, and dilute with dilute sulfuric acid (1 in 10) to 500 mL. Add 7.5 ± 2.5 g of iodine, and mix until solution is complete.
Procedure 1 (3-quinuclidinyl benzilate)
Apply the
Standard solution,
Reference solution 1, and the
Test solution, as directed in the chapter. Place the plate in an unsaturated chromatographic chamber containing freshly prepared
Developing solvent system, and allow the solvent front to move 10 cm. Remove the plate, dry at 105
for 10 minutes, cool, and spray with
potassium iodoplatinate TS: the
RF value of the principal spot obtained from the
Test solution corresponds to that obtained from the
Standard solution, and the
Test solution shows no spot at an
RF value (about 0.8) corresponding to that of 3-quinuclidinyl benzilate.
Procedure 2 (limit of clidinium bromide related compound A)
Apply
Reference solution 2 and the
Test solution to a second
Chromatographic plate as directed in the chapter. Place the plate in an unsaturated chromatographic chamber containing freshly prepared
Developing solvent system, and allow the solvent front to move 15 cm. Remove the plate, dry at 105
for 10 minutes, cool, and spray with
Spray reagent. Any spot in the chromatogram obtained from the
Test solution at an
RF value of about 0.4 is not greater in size or intensity than the minor spot obtained from
Reference solution 2: not more than 0.5% of clidinium bromide related compound A is found.
Assay
Dissolve about 1.2 g of Clidinium Bromide, accurately weighed, in 80 mL of glacial acetic acid, warming if necessary to effect solution. Cool, add 15 mL of
mercuric acetate TS, and titrate with 0.1 N perchloric acid in dioxane VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 43.24 mg of C
22H
26BrNO
3.