Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Methyl Haloacetates Part 5, Assay and Identification of Standard-Grade Reference Materials: Specifications and Tests eISBN: 9780841230460 Tom Tyner Chair, ACS Committee on Analytical Reagents James Francis Secretary, ACS Committee on Analytical Reagents
Downloaded by CORNELL UNIV on June 15, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.5005
ABSTRACT This ACS Reagent Chemicals Standard-Grade Reference Materials monograph for Methyl Haloacetates, in addition to common physical constants, details the following specifications and corresponding tests for verifying that a substance meets ACS Standard-Grade specifications including: Identity by Gas Chromatography−Mass Spectrometry and Assay by Gas Chromatography.
SPECIFICATIONS Identity by Gas chromatography−mass spectrometry. . . . . Passes test
Assay by Gas chromatography . . . . . . . . . . . . . . . . . ≥98.0% Liquid chromatography . . . . . . . . . . . . . . . . ≥98.0%
TESTS Identity by Gas Chromatography−Mass Spectrometry Analyze the sample by gas chromatography–mass spectrometry using method GCMS−MHA1 described below. Method GCMS−MHA1 Ionization Mode . . . . . . . . . . . . . . . . . . . . Electron ionization/70 eV Column . . . . . . . . . . . . . . . . . . . . . . . . . . 5% Diphenyl–95% dimethylpolysiloxane, 30 m × 0.25 mm ID, 0.25 µm film thickness Temperature Program. . . . . . . . . . . . . . . . . 50 °C, hold 1 min, then 10 °C/min to 270 °C Carrier Gas . . . . . . . . . . . . . . . . . . . . . . . Helium at 0.8 mL/min Injector . . . . . . . . . . . . . . . . . . . . . . . . . Split/splitless (100:1 split) Injector Temperature . . . . . . . . . . . . . . . . . 250 °C Scan Range . . . . . . . . . . . . . . . . . . . . . . . 50–550 amu Sample Size . . . . . . . . . . . . . . . . . . . . . . . 0.5 µL of a 50 µg/mL solution
© 2017 American Chemical Society
A
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.5005 ACS Reagent Chemicals, Part 5
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
The identifying ions for the compounds listed in Table 5-4 must be present. The spectrum is compared to the NIST standardized library of compounds, if available. Ions in the test spectrum must match those found in the NIST spectrum.
Downloaded by CORNELL UNIV on June 15, 2017 | http://pubs.acs.org Publication Date (Web): February 28, 2017 | doi: 10.1021/acsreagents.5005
Table 5-4. Methyl Haloacetates Compound Data
Name
CAS No.
Chemical Formula
Formula Weight
MS (m/Z) MS-1
MS (m/Z) MS-2
MS (m/Z) MS-3
Methyl bromoacetate
96-32-2
C3H5BrO2
152.98
152
93
59
Methyl bromochloroacetate
20428-74-4
C3H4BrClO2
187.42
129
127
59
Methyl bromodichloroacetate 20428-76-6
C3H3BrCl2O2
221.86
163
141
59
Methyl chloroacetate
C3H5ClO2
108.52
108
77
59
Methyl chlorodibromoacetate 20428-75-5
96-34-4
C3H3Br2ClO2
266.31
207
187
59
Methyl dibromoacetate
6482-26-4
C3H4Br2O2
231.87
232
173
59
Methyl dichloroacetate
116-54-1
C3H4Cl2O2
142.96
85
83
59
Methyl tribromoacetate
3222-05-7
C3H3Br3O2
310.78
310
251
59
Methyl trichloroacetate
598-99-2
C3H3Cl3O2
177.41
141
117
59
Assay by Gas Chromatography Analyze the sample by gas chromatography using method GC–MHA1 described below. Method GC−MHA1 Column . . . . . . . . . . . . . . . . . . . . . . . . . . 5% Diphenyl–95% dimethylpolysiloxane, 30 m × 0.53 mm i.d., 1.5 µm film thickness Detector . . . . . . . . . . . . . . . . . . . . . . . . . Flame ionization Detector Temperature . . . . . . . . . . . . . . . . 300 °C Injector . . . . . . . . . . . . . . . . . . . . . . . . . Splitless Injector Temperature . . . . . . . . . . . . . . . . . 250 °C Sample Size . . . . . . . . . . . . . . . . . . . . . . . 1 µL of a 1000 µg/mL solution Carrier Gas . . . . . . . . . . . . . . . . . . . . . . . Hydrogen at 3.5 mL/min Temperature Program. . . . . . . . . . . . . . . . . 40 °C, then 5 °C/min to 165 °C, then 15 °C/min to 280 °C, hold 5 min Measure the area under all peaks (excluding the solvent peak), and calculate the analyte content in area percent.
© 2017 American Chemical Society
B
ACS Reagent Chemicals ACS Reagent Chemicals; American Chemical Society: Washington, DC, 2017.
DOI:10.1021/acsreagents.5005 ACS Reagent Chemicals, Part 5
