Methyl Haloacetates - American Chemical Society

meets ACS Standard-Grade specifications including: Identity by Gas Chromatography−Mass Spectrometry and Assay by. Gas Chromatography. ... MS (m/Z). ...
1 downloads 5 Views 60KB Size
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