Synthesis of the O-(2,3, 4,5, 6-Pentafluorobenzyl)hydroxylamine Oximes of Selected Carbonyl Compounds and Their Determination by Liquid Chromatography with Ultraviolet Detection

Details

• Personal Author:
  Jehlar A ; Que Hee SS ; Wiesenthal K
• Description:
  The aims were to develop a liquid chromatographic (LC) method with ultraviolet detection (UVD) for O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) O-oximes of common aldehydes and ketones, and to define the steric limits of the synthetic reaction used to make the PFBHA O-oxime standards for gas chromatographic (GC) and LC methods. Ten new O-oximes were synthesized with the new optimized method, and their purities were demonstrated by GC/electron-capture detection (ECD), GC/mass spectrometry (MS), ultraviolet spectroscopy, infrared spectroscopy, and proton and 13C-nuclear magnetic resonance spectroscopy. Ketones substituted at both beta-carbons relative to the carbonyl carbon, like diisobutyl ketone and 2,4-hexanedione, showed lower synthetic yields by wet chemistry methods. A new C18 reverse-phase LC method with UVD at 200 nm and acetonitrile-water in both the isocratic and gradient-elution modes was then developed to sensitively resolve a mixture of 13 pure PFBHA O-oximes. The detection limit was near 100 ng O-oxime/mL or about 14-50 ng aldehyde/mL and the least quantifiable limits were near 500 ng/mL or about 70-250 ng aldehyde/mL, with lower limits for glyoxal, methylglyoxal, benzaldehyde, and acetophenone. Carbonyl compounds in 500 mL water samples were then determined in distilled water and tap water by gradient elution. Vapors of n-valeraldehyde and acrolein generated in gas bags at concentrations near occupational guidelines were also sampled, desorbed, and then determined by either isocratic or gradient elution at 200 or 254 nm within 30-45 min. [Description provided by NIOSH]
• Subjects:
  Aldehydes Butanones Chemistry Chromatography Formaldehyde Occupational Health Safety Ultraviolet Rays
• Keywords:
  Carbonyls Chemical-synthesis Chromatographic-analysis Gas-chromatography Ketones Ultraviolet-light Ultraviolet-spectrometry
• ISSN:
  1060-3271
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  83
• Issue:
  4
• NIOSHTIC Number:
  nn:20029976
• Citation:
  J AOAC Int 2000 Jul; 83(4):859-869
• Contact Point Address:
  Department of Environmental Health Sciences and UCLA Center for Occupational and Environmental Health, Los Angeles, CA 90095-1772
• Federal Fiscal Year:
  2000
• NORA Priority Area:
  Research Tools and Approaches: Exposure Assessment Methods
• Performing Organization:
  University of California Los Angeles, Los Angeles, CA
• Peer Reviewed:
  True
• Start Date:
  19950901
• Source Full Name:
  Journal of AOAC International
• End Date:
  19990831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a18b85a7e0e7d6bc7096b24707b9af2e25fcf77783ae1af77b0d03397cc4a1d9f0a2bb5467b20e165b0d18c20bf3f0c9d85e5b031352389930a2afc12ccc6281
• Download URL:
  https://stacks.cdc.gov/view/cdc/190839/cdc_190839_DS1.pdf
• File Type:
  [PDF - 191.26 KB ]