2,4,7,9-tetramethyl-5-decyne-4,7-diol
Structural formula | ||||||||||||||||
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Simplified structural formula without stereochemistry | ||||||||||||||||
General | ||||||||||||||||
Surname | 2,4,7,9-tetramethyl-5-decyne-4,7-diol | |||||||||||||||
other names |
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Molecular formula | C 14 H 26 O 2 | |||||||||||||||
Brief description |
white solid |
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properties | ||||||||||||||||
Molar mass | 226.36 g mol −1 | |||||||||||||||
Physical state |
firmly |
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Melting point |
42-44 ° C |
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boiling point |
255 ° C |
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Vapor pressure |
0.7 Pa (20 ° C) |
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solubility |
poor in water (1.5 g l −1 at 20 ° C) |
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safety instructions | ||||||||||||||||
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Toxicological data | ||||||||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
2,4,7,9-Tetramethyl-5-decyne-4,7-diol ( TMDD for short ) is a surfactant and - unless otherwise stated - a mixture of three stereoisomeric chemical compounds from the group of diols with an additional C ≡C- triple bond . It is used as a foam inhibitor and as a wetting agent.
Occurrence
In water investigations it was found in the Rhine and its tributaries, the Ruhr , Wupper , Lippe and Sieg , as well as in the Nidda , Elbe , Mulde and Maas . More than 1000 tons are supposed to get into the environment every year. An examination of the TMDD concentrations in sewage, sewage treatment plants and running waters suggested that paints and printing inks are a significant source of TMDD.
Extraction and presentation
TMDD is made from acetylene and methyl isobutyl ketone in the presence of potassium hydroxide .
properties
2,4,7,9-Tetramethyl-5-decyne-4,7-diol is a white solid with poor water solubility and volatility. It is a tertiary glycol (double alcohol) with a triple bond.
Stereoisomers
It contains two stereogenic centers in the 4- and 7-positions, which are equally substituted. As a result, there are three stereoisomers: (4 S , 7 S ) -TMDD, the mirror image of (4 R , 7 R ) -TMDD and meso -TMDD. The scientific literature on TMDD deals almost exclusively with the mixture of the three stereoisomers .
(4 R , 7 R ) -TMDD (top), (4 S , 7 S ) -TMDD (middle) and meso -TMDD (bottom)
use
2,4,7,9-Tetramethyl-5-decyne-4,7-diol is a non-ionic surfactant that is used, for example, under the brand name Surfynol 1004E for a variety of industrial purposes. It is usually used to lower the surface tension of aqueous formulations and thus to increase the wettability of surfaces. Typical application examples are printing inks, defoaming agents or dispersants. Due to its surface-active properties, TMDD is also added to formulations of crop protection agents.
Individual evidence
- ↑ a b c data sheet 2,4,7,9-tetramethyl-5-decyne-4,7-diol, mixture of (±) and meso from Sigma-Aldrich , accessed on April 23, 2011 ( PDF ).
- ↑ a b 2,4,7,9-tetramethyl-5-decyne-4,7-diol. ( Memento of April 18, 2013 in the web archive archive.today ) Information on substances, KEMI Swedish Chemicals Agency, 2007 (English).
- ↑ a b Entry on 2,4,7,9-tetramethyldec-5-yn-4,7-diol in the GESTIS substance database of the IFA , accessed on February 8, 2018(JavaScript required) .
- ↑ Data sheet 2,4,7,9-tetramethyl-5-decyne-4,7-diol from Acros, accessed on June 23, 2006.
- ↑ Larissa Dsikowitzky: Environmental geochemical characterization of the low molecular weight organic load of the Lippe river system. Dissertation, 2002, DNB 96943636x / 34 .
- ↑ Volker Mrasek : TMDD-Research: Mysterious pollutant pollutes German rivers. In: Spiegel Online . October 1, 2008, accessed January 22, 2015 .
- ↑ Arlen Guedez Orozco: Occurrence and sources of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) in the aquatic environment. Doctoral thesis, Univ. Frankfurt, 2011 urn : nbn: de: hebis: 30: 3-242548 .
- ↑ a b c H.-J. Brauch, F. Sacher: Statement by the DVGW Technology Center for Water (TZW) on 2,4,7,9-tetramethyl-5-decyn-4,7-diol (TMDD) .
- ↑ Entry on 2,4,7,9-tetramethyl-5-decyne-4,7-diol in the Hazardous Substances Data Bank , accessed December 4, 2018.