Dimethylbenzylamine

Synthesis

N,N-Dimethylbenzylamine can be synthesized by the Eschweiler–Clarke reaction of benzylamine

Reactions

It undergoes directed ortho metalation with butyl lithium:

:C6H5CH2N(CH3)2 + BuLi → 2-LiC6H4CH2N(CH3)2 :LiC6H4CH2N(CH3)2 + E+ → 2-EC6H4CH2N(CH3)2

Via these reactions, many derivatives are known with the formula 2-X-C6H4CH2N(CH3)2 (E = SR, PR2, etc.).

The amine is basic and undergoes [quaternization with alkyl halides (e.g. hexyl bromide) to give quaternary ammonium salts:

:[C6H5CH2N(CH3)2 + RX → [C6H5CH2N(CH3)2R]+X−

Such salts are useful phase transfer catalysts.

Uses

As the molecule has tertiary amine functionality, two of the key uses are as an epoxy-amine cure enhancement catalyst and also as a polyurethane catalyst.

References

References

1. "N,N-dimethyl benzyl amine".
2. (1945). "β-Phenylethyldimethylamine". Organic Syntheses.
3. (1933). "The Action of Formaldehyde on Amines and Amino Acids". [[J. Am. Chem. Soc.]].
4. W. R. Brasen. (1954). "o-Methylethylbenzyl Alcohol". Org. Synth..
5. (June 2003). "Study of the effect of BDMA catalyst in the epoxy novolac curing process by isothermal DSC". Polymer International.
6. (March 2005). "Study of the Effect of BDMA Catalyst in Epoxy Novolac Curing Process by Isothermal DSC". Journal of Reinforced Plastics and Composites.
7. (2018-07-15). "Effects of different catalysts on the structure and properties of polyurethane/water glass grouting materials". Journal of Applied Polymer Science.
8. (2003). "Benzyldimethylamine (BDMA): Catalyst of Choice with Epoxy Embedding Media". Microscopy Today.