12-crown-4

Structural formula
General
Surname	[12] Crown-4
other names	1,4,7,10-tetraoxacyclododecane
Molecular formula	C 8 H 16 O 4
Brief description	colorless liquid
External identifiers / databases
EC number	206-036-5
ECHA InfoCard	100.005.488
PubChem	9269
Wikidata	Q4261972
properties
Molar mass	176.21 g mol −1
Physical state	liquid
density	1.089 g cm −3 (25 ° C)
Melting point	16 ° C
boiling point	61-70 ° C (0.5 mmHg)
Vapor pressure	0.04 hPa (20 ° C)
solubility	soluble in water
Refractive index	1.463 (20 ° C)
safety instructions
GHS labeling of hazardous substances	no GHS pictograms
	no GHS pictograms
H and P phrases	H: no H-phrases
	P: no P-phrases
Toxicological data	2830 mg kg −1 ( LD 50 , rat , oral ) ; 5028 mg kg −1 ( LD 50 , rabbit , transdermal ) ;
	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

[12] Crown-4 is a chemical compound from the group of crown ethers .

Extraction and presentation

[12] Crown-4 can be obtained by cyclizing tetraethylene glycol with lithium hydroxide . Synthesis by reaction of ethylene glycol with 1,8-dichloro-3,6-dioxaoctane in the presence of lithium perchlorate and sodium hydroxide and dimethyl sulfoxide as solvents is also possible .

properties

[12] Krone-4 is a colorless liquid that is soluble in water. It forms complexes with lithium ions, since the ion with its size of 120 pm fits very well into the interior of the compound.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k data sheet 12-Crown-4, Cyclic tetramer of ethylene oxide which is specific for the lithium cation. 98% from Sigma-Aldrich , accessed on September 5, 2015 ( PDF ).
↑ ^a ^b Data sheet 12-Krone-4 (PDF) from Merck , accessed on September 5, 2015.
↑ M. Hiraoka: Crown Ethers and Analogous Compounds . Elsevier, 2013, ISBN 978-1-4832-9087-4 , pp. 19 ( limited preview in Google Book search).
^ VK Ahluwalia, Renu Aggarwal: Organic Synthesis Special Techniques . CRC Press, 2001, ISBN 978-0-8493-1002-7 , pp. 73 ( limited preview in Google Book search).
↑ Paula Yurkanis Bruice: Organic Chemistry compact studying . Pearson Deutschland GmbH, 2011, ISBN 978-3-86894-102-9 , pp. 426 ( limited preview in Google Book search).

[Sigma-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k data sheet 12-Crown-4, Cyclic tetramer of ethylene oxide which is specific for the lithium cation. 98% from Sigma-Aldrich , accessed on September 5, 2015 ( PDF ).

[Merck-2] Data sheet 12-Krone-4 (PDF) from Merck , accessed on September 5, 2015.

[M._Hiraoka-3] M. Hiraoka: Crown Ethers and Analogous Compounds . Elsevier, 2013, ISBN 978-1-4832-9087-4 , pp. 19 ( limited preview in Google Book search).

[V._K._Ahluwalia,_Renu_Aggarwal-4] VK Ahluwalia, Renu Aggarwal: Organic Synthesis Special Techniques . CRC Press, 2001, ISBN 978-0-8493-1002-7 , pp. 73 ( limited preview in Google Book search).

[Paula_Yurkanis_Bruice-5] Paula Yurkanis Bruice: Organic Chemistry compact studying . Pearson Deutschland GmbH, 2011, ISBN 978-3-86894-102-9 , pp. 426 ( limited preview in Google Book search).