Ethyl (S)-4-Chloro-3-hydroxybutyrate CAS 86728-85-0 Atorvastatin Calcium Intermediate

Ethyl (S)-4-Chloro-3-hydroxybutyrate (CAS: 86728-85-0)
Method of analysis
Description
Take about 10ml sample in a clean and dry glass plate and check.
Specific rotation
Transfer accurately about 1.0g of sample to 100ml volumetric flask and dissolved in 10 ml of chloroform, then dilute with chloroform to 100ml and mix.
Measure the optical rotation of the test sample at 25ºC and 589nm wavelength calculate the specific rotation as per the given formula.
[α]25D = (v×a)/[w×(1-b)]
[α]25D: the specific rotation of test sample; α: the observed rotation in angular degree; w: sample weight (g);
v: volume (mL);
b: Water content(%)
Purity (by GC)
Chromatographic conditions: The Gas chromatography is equipped with flame ionization detector
Column: SE-54, 30m×0.35mm×0.25µm
Oven temperature: Initial temp 120℃, Hold time for 2min
Ramp: 20℃/min
Temp: 250℃, Hold time for 2min
Injector temperature: 250℃
Detector temperature: 250℃(FID)
Injection volume: 0.2µl
Sample solution: dilute 1ml A4 with 1ml acetone.
Procedure: Inject 0.2µl of the acetone as blank and record the chromatogram. In the chromatogram obtained from diluent there should not be any interference at the retention time of the main peak and impurity peak. Than Inject the sample solution in duplicate into the chromatograph and record the chromatogram. Report the Purity of sample by area normalization method.