Glycidol

Structural formula
Structural formula without stereochemistry
General
Surname	Glycidol
other names	2,3-epoxy-1-propanol Oxirane-2-methanol Glycid Glycidic alcohol Glyceryl glycide
Molecular formula	C 3 H 6 O 2
Brief description	colorless and odorless liquid
External identifiers / databases
CAS number 556-52-5 ( racemate ) 57044-25-4 [( R ) -isomer] 60456-23-7 [( S ) -isomer] EC number 209-128-3 ECHA InfoCard 100.008.300 PubChem 11164 ChemSpider 10691 Wikidata Q418265
properties
Molar mass	74.08 g mol −1
Physical state	liquid
density	1.1143 g cm −3 (racemate)
Melting point	−54 ° C
boiling point	161 ° C (decomposition)
Vapor pressure	1.2 h Pa (25 ° C)
solubility	miscible with water soluble in lower alcohols, ketones, ethers, benzene insoluble in aliphatic hydrocarbons
Refractive index	1.433 (20 ° C)
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 302-312-330-315-319-341-350-360F-373 P: 280-302 + 352-304 + 340-310-305 + 351 + 338-362
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Glycidol is an organic chemical compound from the groups of epoxides ( oxiranes ) and alcohols . The substance is a clear, odorless and tasteless liquid that slowly reacts with water to form glycerine . The glycidol molecule is chiral and therefore occurs in two different, mirror-image enantiomers .

Physical Properties

The rotation value for undiluted ( R ) - (+) - glycidol at 23 ° C ( sodium D-line ) is + 15 °.

Manufacturing

Racemic glycidol can be obtained by dehalogenation and epoxide formation from 3-chloro-1,2-propanediol with bases .

Glycidol can also be synthesized from allyl alcohol and tert-butyl hydroperoxide and in the presence of catalytic amounts of vanadium (IV) oxy (acetylacetonate) (VO (acac) ₂ ).

Likewise by oxidation of allyl alcohol with cumene hydroperoxide , the ( R ) - or the ( S ) - enantiomer can be selectively represented stereospecifically in a Sharpless epoxidation in the presence of titanium tetraethoxide or titanium tetraisopropoxide and diethyl tartrate as chiral auxiliary .

Reactions

By reacting the epoxy group , glycidol can enter into a variety of reactions with nucleophiles . With alcohols formed via ring opening ether . Both esters and ethers can be formed via the OH group .

use

Glycidol is used as a stabilizer for vegetable oils and vinyl polymers and to separate emulsions . It is also used to manufacture surfactants , pharmaceuticals, synthetic resins and finishing agents for textiles. Glycidol-based ethers and esters are used as epoxy resins and as reactive thinners in paints , adhesives and coatings .

safety instructions

In the presence of suitable catalysts , glycidol can polymerize explosively. The substance is carcinogenic , strongly irritates the mucous membranes and the skin and, if it comes into contact with it, causes serious eye damage through damage to the cornea . The central nervous system can be stimulated, with subsequent possible depression . In animal experiments with rats and mice, glycidol was shown to be genotoxic and carcinogenic and caused reduced fertility and even sterility .

In Baden-Württemberg , glycidol fatty acid esters were found in vegetable edible oils such as palm oil , which can arise during refining . These esters hydrolyze to fatty acids and glycidol in the human digestive tract . The BfR therefore advises against the use of baby food containing palm oil.

literature

• Beilstein's Handbook of Organic Chemistry E, III / IV, 17: 985.

Web links

• The bad trick with the fat - excitement about glycidol

Individual evidence

1. ↑ ^{a b c d e f g} Entry on 2,3-epoxy-1-propanol in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
2. ^ The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals , 14th Edition (Merck & Co., Inc.), Whitehouse Station, NJ, USA, 2006, ISBN 978-0-911910-00-1 ; Pp. 775-776.
3. ↑ David R. Lide: CRC Handbook of Chemistry and Physics . 85th edition, 2005, CRC Press, chap. 3, p. 444.
4. ↑ Entry on glycidol. In: Römpp Online . Georg Thieme Verlag, accessed on June 16, 2014.
5. ↑ Glycidol data sheet from Sigma-Aldrich , accessed on April 3, 2011 ( PDF ).
6. ↑ Entry on 2,3-epoxypropan-1-ol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
7. ↑ Data sheet (R) - (+) - Glycidol 97% from Sigma-Aldrich , accessed on January 18, 2013 ( PDF ).
8. ↑ ^{a b} Joachim Buddrus: In Fundamentals of Organic Chemistry , pp. 184-185, 4th edition. Walter de Gruyter GmbH & Co. KG Berlin / New York 2011, ISBN 3-11-024894-8 .
9. ↑ Leo A. Paquette: Handbook of Reagents for Organic Synthesis: Chiral reagents for asymmetric synthesis. John Wiley and Sons, 2003, ISBN 978-0-470-85625-3 , p. 345.
10. ↑ Jeffrey W. Vincoli: Risk management for hazardous chemicals. Volume 2, CRC Press, 1997, ISBN 978-1-56670-200-3 , p. 1563.
11. ↑ BauA : 2,3-Epoxypropan-1-ol (Glycidol) , May 15, 2002.
12. ↑ Questions and answers on glycidol fatty acid esters FAQ of the BfR of April 30, 2009.