Lithium tetramethylpiperidide

Structural formula
General
Surname	Lithium tetramethylpiperidide
other names	Lithium 2,2,6,6-tetramethylpiperidide; 2,2,6,6-tetramethylpiperidine lithium; LTMP; LiTMP;
Molecular formula	C 9 H 18 LiN
External identifiers / databases
EC number	684-475-5
ECHA InfoCard	100.209.926
PubChem	11051814
Wikidata	Q1110352
properties
Molar mass	147.19 g mol −1
Physical state	firmly
solubility	soluble in most organic solvents
safety instructions
H and P phrases	H: 261-314
	P: 231 + 232-280-305 + 351 + 338-310-422
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Lithium tetramethylpiperidide is a chemical compound of lithium from the group of piperidines .

Extraction and presentation

Lithium tetramethylpiperidide can be obtained by reacting dry 2,2,6,6-tetramethylpiperidine with n -butyllithium in diethyl ether or tetrahydrofuran solution.

properties

Lithium tetramethylpiperidide is in THF solution as a dimer-monomer equilibrium mixture, with additives such as HMPA increasing the monomer concentration. The X-ray structure determination shows that the compound crystallizes as a tetramer from n- hexane / pentane mixtures.

use

Lithium tetramethylpiperidide may be for the selective deprotonation of aromatics , heteroaromatics and aliphatic compounds are used in the presence of a variety of functional groups.

Individual evidence

↑ ^a ^b ^c data sheet Lithium 2,2,6,6-tetramethylpiperidide, 97% from Sigma-Aldrich , accessed on March 8, 2018 ( PDF ).
↑ ^a ^b ^c ^d Brett L. Lucht, and David B. Collum: Structure of Lithium 2,2,6,6-Tetramethylpiperidine (LiTMP) and Lithium 2,2,4,6,6-Pentamethylpiperidide (LiPMP) in Hydrocarbon Solution : Assignment of Cyclic Trimer and Tetramer Conformational Isomers, J. Am. Chem. Soc., 1994, 116 (17), pp 7949-7950, doi: 10.1021 / ja00096a083
↑ Brett L. Lucht, David B. Collum: Structure of Lithium 2,2,6,6-Tetramethylpiperidine (LiTMP) and Lithium 2,2,4,6,6-Pentamethylpiperidide (LiPMP) in Hydrocarbon Solution: Assignment of Cyclic Trimer and Tetramer Conformational Isomers. In: Journal of the American Chemical Society. 116, 1994, p. 7949, doi: 10.1021 / ja00096a083 .
↑ Sean H. Wiedemann, Antonio Ramírez, David B. Collum: Lithium 2,2,6,6-Tetramethylpiperidide-Mediated α- and β-Lithiations of Epoxides: Solvent-Dependent Mechanisms. In: Journal of the American Chemical Society. 125, 2003, p. 15893, doi: 10.1021 / ja0304087 .
↑ Jonathan Clayden: Organolithiums Selectivity for Synthesis . Elsevier, 2002, ISBN 978-0-08-043261-8 , pp. 69 ( limited preview in Google Book search).

[Sigma-1] ta sheet Lithium 2,2,6,6-tetramethylpiperidide, 97% from Sigma-Aldrich , accessed on March 8, 2018 ( PDF ).

[Brett_L._Lucht,_and_David_B._Collum-2] Brett L. Lucht, and David B. Collum: Structure of Lithium 2,2,6,6-Tetramethylpiperidine (LiTMP) and Lithium 2,2,4,6,6-Pentamethylpiperidide (LiPMP) in Hydrocarbon Solution : Assignment of Cyclic Trimer and Tetramer Conformational Isomers, J. Am. Chem. Soc., 1994, 116 (17), pp 7949-7950, doi: 10.1021 / ja00096a083

[DOI10.1021/ja00096a083-3] Brett L. Lucht, David B. Collum: Structure of Lithium 2,2,6,6-Tetramethylpiperidine (LiTMP) and Lithium 2,2,4,6,6-Pentamethylpiperidide (LiPMP) in Hydrocarbon Solution: Assignment of Cyclic Trimer and Tetramer Conformational Isomers. In: Journal of the American Chemical Society. 116, 1994, p. 7949, doi: 10.1021 / ja00096a083 .

[DOI10.1021/ja0304087-4] Sean H. Wiedemann, Antonio Ramírez, David B. Collum: Lithium 2,2,6,6-Tetramethylpiperidide-Mediated α- and β-Lithiations of Epoxides: Solvent-Dependent Mechanisms. In: Journal of the American Chemical Society. 125, 2003, p. 15893, doi: 10.1021 / ja0304087 .

[Jonathan_Clayden-5] Jonathan Clayden: Organolithiums Selectivity for Synthesis . Elsevier, 2002, ISBN 978-0-08-043261-8 , pp. 69 ( limited preview in Google Book search).