2,2,6,6-Tetramethylpiperidine

2,2,6,6-Tetramethylpiperidine

IUPAC name	2,2,6,6-Tetramethylpiperidine
Other names	Norpempidine Tetramethylpiperidine
Identifiers
Abbreviations	TMP
CAS number	768-66-1
PubChem	13035
EINECS number	212-199-3
SMILES	CC1(C)CCCC(C)(C)N1
Properties
Molecular formula	C₉H₁₉N
Molar mass	141.25 g mol^-1
Appearance	Clear yellow liquid
Density	0.83 g/mL
Melting point	-59 °C, 214 K, -74 °F
Boiling point	152 °C, 425 K, 306 °F
Hazards
R-phrases	R10 R22 R36/37/38
S-phrases	S16 S26 S37/39
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

2,2,6,6-Tetramethylpiperidine or TMP or HTMP is a clear light yellow liquid with an amine odor. This amine is used in chemistry as a hindered base because it can dissolve in organic solvents unlike ordinary bases such as potassium hydroxide.

Additional recommended knowledge

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There are many ways to synthesise TMP. One recent method^[1] starts with a conjugate addition reaction of ammonia to phorone. The intermediate triacetone amine is then reduced in a Wolff-Kishner reaction.

TMP is the starting material for an even stronger base lithium tetramethylpiperidide and the radical species TEMPO. Another non-nucleophilic base is N,N-diisopropylethylamine.

References

^ A Large-Scale Low-Cost Access to the Lithium 2,2,6,6-Tetramethylpiperidide Precursor Detlef Kampmann, Georg Stuhlmüller, Roger Simon, Fabrice Cottet, Frédéric Leroux, Manfred Schlosser Synthesis 2005 1028-1029 Abstract

Categories: Piperidines | Reagents for organic chemistry