Nitrobenzyl alcohols

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Nitrobenzyl alcohols
Surname 2-nitrobenzyl alcohol 3-nitrobenzyl alcohol 4-nitrobenzyl alcohol
other names o -nitrobenzyl alcohol m -nitrobenzyl alcohol p -nitrobenzyl alcohol
Structural formula Structure of 2-nitrobenzyl alcohol Structure of 3-nitrobenzyl alcohol Structure of 4-nitrobenzyl alcohol
CAS number 612-25-9 619-25-0 619-73-8
PubChem 11923 69267 69275
Molecular formula C 7 H 7 NO 3
Molar mass 153.14 g mol −1
Physical state firmly
Melting point 69-72 ° C 30-32 ° C 92-94 ° C
boiling point 270 ° C
  		175-180 ° C
(3  mmHg ) 		185 ° C
(12 mmHg)
GHS
labeling
no GHS pictograms
no GHS pictograms
no GHS pictograms
H and P phrases no H-phrases no H-phrases no H-phrases
no EUH phrases no EUH phrases no EUH phrases
no P-phrases no P-phrases no P-phrases

In chemistry, nitrobenzyl alcohols form a group of substances that are derived from both benzyl alcohol and nitrobenzene . The structure consists of a benzene ring with attached hydroxymethyl  (-CH 2 OH) and nitro group  (-NO 2 ) as substituents . Their different arrangements ( ortho , meta or para ) result in three constitutional isomers with the empirical formula C 7 H 7 NO 3 .

presentation

The nitrobenzyl alcohols can be prepared from the nitrobenzoyl chlorides in anhydrous dioxane by reduction with sodium borohydride (NaBH 4 ) . They can also be obtained from the nitrobenzaldehydes by means of the Meerwein-Ponndorf-Verley reduction . In the basic medium, the nitrobenzaldehydes disproportionate to nitrobenzoic acids and nitrobenzyl alcohols.

properties

The nitrobenzyl alcohols are solids. The 4-nitrobenzyl alcohol, which has the highest symmetry, has the highest melting point.

use

In mass spectrometry , 3-nitrobenzyl alcohol (often abbreviated as "3-NBA") is used as a liquid matrix for fast atom bombardment and matrix-assisted laser desorption / ionization .

Individual evidence

  1. ↑ a b c data sheet 2-nitrobenzyl alcohol from Sigma-Aldrich , accessed on March 12, 2017 ( PDF ).
  2. ↑ a b c data sheet 3-nitrobenzyl alcohol from Sigma-Aldrich , accessed on March 12, 2017 ( PDF ).
  3. ↑ a b c data sheet 4-nitrobenzyl alcohol from Sigma-Aldrich , accessed on March 12, 2017 ( PDF ).
  4. ↑ a b c CRC Handbook of Tables for Organic Compound Identification , Third Edition, 1984, ISBN 0-8493-0303-6 .
  5. ^ Gattermann / Wieland : The practice of organic chemists , 43rd edition, Walter de Gruyter , Berlin · New York 1982, ISBN 3-11-006654-8 , pp. 540-541: " p -nitrobenzyl alcohol".
  6. ↑ Representation of o -nitrobenzyl alcohol (PDF file; 81 kB).
  7. ↑ J. Meili, J. Seibl: A new versatile matrix for fast atom bombardment analysis ; in: Organic Mass Spectrometry , 1984 , 19  (11), pp. 581-582 ( doi: 10.1002 / oms.1210191111 ).
  8. ↑ Shankai Zhao, Kasi V. Somayajula, Andrew G. Sharkey, David M. Hercules, Franz Hillenkamp, ​​Michael Karas, Arndt Ingendoh: Novel Method for Matrix-Assisted Laser Mass Spectrometry of Proteins ; in: Anal. Chem. , 1991 , 63  (5), pp. 450-453 ( doi: 10.1021 / ac00005a012 ).
  9. ↑ TW. Dominic Chan, AW Colburn, Peter J. Derrick: Matrix-assisted laser desorption / ionization using a liquid matrix: Formation of high-mass cluster ions from proteins ; in: Organic Mass Spectrometry , 1992 , 27  (1), pp. 53-56 ( doi: 10.1002 / oms.1210270114 ).

See also

Web links

Commons : Nitrobenzyl Alcohols  - Collection of pictures, videos and audio files