Phenyllithium

Structural formula
General
Surname	Phenyllithium
other names	Lithium phenyl; LiPh;
Molecular formula	C 6 H 5 Li
External identifiers / databases
EC number	209-720-1
ECHA InfoCard	100,008,838
PubChem	637932
Wikidata	Q419478
properties
Molar mass	84.04 g mol −1
Physical state	firmly
Melting point	150 ° C (decomposition)
solubility	reacts violently with water
safety instructions
GHS labeling of hazardous substances for the 1.9 M solution in di- n -butyl ether; Caution
H and P phrases	H: 315-319-335-412
	P: 261-273-305 + 351 + 338
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Phenyllithium is an organometallic compound of the element lithium and is therefore one of the organolithium compounds .

Extraction and presentation

Phenyllithium is made from metallic lithium and bromobenzene or chlorobenzene analogously to the Grignard compounds .

{\ displaystyle \ mathrm {C_ {6} H_ {5} Br + 2 \ Li \ longrightarrow \ C_ {6} H_ {5} Li + LiBr}}

Another way of showing this is the reaction of benzene with n-butyllithium . As a stronger CH-acidic compound compared to n-BuLi, benzene can be metalated in the presence of σ donors (e.g. TMEDA ).

{\ displaystyle \ mathrm {C_ {6} H_ {6} + C_ {4} H_ {9} Li \ longrightarrow \ C_ {6} H_ {5} Li + C_ {4} H_ {10}}}

TMEDA splits the n -BuLi oligomer in solution into monomers and polarizes the Li – C bond by complexing it.

properties

Phenyllithium crystallizes in the solid state in an infinite, polymeric conductor structure. The bond of the ipso carbon with the two lithium atoms in the dimeric Li ₂ C ₂ subunits is based on a 2-electron-3-center bond (2e-3c). In addition, there is a strong interaction of the π-electrons of the phenyl rings with the lithium atoms of the neighboring units.

In solution, phenyllithium can form a variety of structures, which depend on the solvent. Monomeric, dimeric, trimeric (6-membered ring), tetrameric (heterocubane) and hexameric (octahedron, hexagonal) structures are known.

In THF phenyllithium exists as a mixture of monomers and dimers, in TMEDA dimer and diethyl ether dimer and tetramer.

use

Phenyllithium is used in organic chemistry for a number of syntheses (for example in the formation of biphenyls through nucleophilic aromatic substitutions). It is available in technical form as a low-percentage solution (usually around 20%) in various solvents such as di- n- butyl ether , cyclohexane / ether.

safety instructions

Phenyllithium is corrosive, highly flammable, highly reactive and reacts violently with water.

Web links

Aggregation and Reactivity of Phenyllithium Solutions; doi : 10.1021 / ja980684z
Method of making Phenyllithium (Freepatentsonline)

Individual evidence

↑ ^a ^b Entry on phenyllithium. In: Römpp Online . Georg Thieme Verlag, accessed on June 21, 2014.
↑ ^a ^b Datasheet Phenyllithium solution 1.9 M in dibutyl ether from Sigma-Aldrich , accessed on April 19, 2011 ( PDF ).
↑ Parts of the labeling of hazardous substances relate to the hazards caused by the solvent.
^ Gattermann and Wieland, The Practice of Organic Chemists, ISBN 3-11-006654-8 .
↑ Christoph Elschenbroich, Organometallchemie, 5th edition - Teubner Verlag, 2005, p. 47
↑ Robert E. Dinnebier: Determination of the crystal structure of molecular substances from X-ray diffraction images on powders ( Memento from May 14, 2011 in the Internet Archive ), (pdf, 4.1 MB)
^ Robert E. Dinnebier, Ulrich Behrens, Falk Olbrich: Lewis Base-Free Phenyllithium - J. Am. Chem. Soc., 1998, 120 (7), pp 1430-1433, doi : 10.1021 / ja972816e .
↑ Hans J. Reich et al. Aggregation and Reactivity of Phenyllithium Solutions ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The @1@ 2 archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 538 kB) - J. Am. Chem. Soc. 1998, 120, pp 7201-7210 (accessed June 24, 2011)

↑ Phenyllithium data sheet (PDF) from Merck , accessed on February 23, 2010.

↑ Phenyllithium solution data sheet from Sigma-Aldrich , accessed on November 4, 2016 ( PDF ).

[CDRömpp-1] Entry on phenyllithium. In: Römpp Online . Georg Thieme Verlag, accessed on June 21, 2014.

[Sigma-2] Datasheet Phenyllithium solution 1.9 M in dibutyl ether from Sigma-Aldrich , accessed on April 19, 2011 ( PDF ).

[LM-3] Parts of the labeling of hazardous substances relate to the hazards caused by the solvent.

[4] Gattermann and Wieland, The Practice of Organic Chemists, ISBN 3-11-006654-8 .

[5] Christoph Elschenbroich, Organometallchemie, 5th edition - Teubner Verlag, 2005, p. 47

[Dinnebier-6] Robert E. Dinnebier: Determination of the crystal structure of molecular substances from X-ray diffraction images on powders ( Memento from May 14, 2011 in the Internet Archive ), (pdf, 4.1 MB)

[7] Robert E. Dinnebier, Ulrich Behrens, Falk Olbrich: Lewis Base-Free Phenyllithium - J. Am. Chem. Soc., 1998, 120 (7), pp 1430-1433, doi : 10.1021 / ja972816e .

[8] Hans J. Reich et al. Aggregation and Reactivity of Phenyllithium Solutions ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The @1@ 2 archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 538 kB) - J. Am. Chem. Soc. 1998, 120, pp 7201-7210 (accessed June 24, 2011)

[9] Phenyllithium data sheet (PDF) from Merck , accessed on February 23, 2010.

[Sigma2-10] Phenyllithium solution data sheet from Sigma-Aldrich , accessed on November 4, 2016 ( PDF ).