1,8-bis ( N , N -dimethylamino) naphthalene
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| Surname | 1,8-bis ( N , N -dimethylamino) naphthalene | ||||||||||||||||||
| other names |
N , N , N ′, N ′ -Tetramethylnaphthalene-1,8-diamine ( IUPAC ) |
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| Molecular formula | C 14 H 18 N 2 | ||||||||||||||||||
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| properties | |||||||||||||||||||
| Molar mass | 214.31 g mol −1 | ||||||||||||||||||
| Physical state |
firmly |
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| Melting point |
45-49 ° C |
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| pK s value |
12.34 |
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| solubility |
almost insoluble in water |
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . | |||||||||||||||||||
1,8-bis ( N , N -dimethylamino) naphthalene is an organic compound . It was first made in 1968 by Roger Alder at the University of Bristol . It is called the model substance of a proton sponge . 1,8-bis (dimethylamino) naphthalene is an aromatic diamine which has two tertiary amino groups in an adjacent position ( peri position ) on the naphthalene ring . This position results in a very high basicity (p K a = 12.34) and special spectroscopic properties.
Structure and properties
With a base constant pKb of 1.66 (acid constant 12.34) 1,8-bis (dimethylamino) naphthalene is one of the strongest known amine bases. Nevertheless, protons are only slowly absorbed. Because of its high basicity and low nucleophilicity , it is used in organic synthesis as a means of deprotonating organic compounds.
Manufacturing
The compound is commercially available. You can by methylation of 1,8-diaminonaphthalene with methyl iodide or dimethyl sulfate are produced.
Other proton sponges
Second generation proton sponges, with an even higher basicity, are 1,8-bis (hexamethyltriaminophosphazenyl) naphthalene or 1,8-bis (hexamethyltriaminophosphazenyl) naphthalene, HMPN: A superbasic bisphosphazene proton sponge is made from 1,8-bis (dimethylamino) naphthalene and tris (dimethylamino) phosphine . HMPN has a pK BH + of 29.9 in acetonitrile .
Web links
Individual evidence
- ↑ a b c Data sheet N, N, N ′, N′-Tetramethyl-1,8-naphthalenediamine from Sigma-Aldrich , accessed on May 19, 2017 ( PDF ).
- ↑ a b c R. W. Alder, PS Bowman, WRS Steele and DR Winterman: The remarkable basicity of 1,8-bis (dimethylamino) naphthalene . In: Chem. Commun. . 1968, p. 723. doi : 10.1039 / C19680000723 .
- ^ Entry on 1,8-bis (dimethylamino) naphthalenes at ChemicalBook , accessed October 24, 2009.
- ↑ F. Gerson, E.Haselbach and G. Plattner: Radical anion of 1,8-bis (dimethylamino) naphthalene ( "proton sponge") . (abstract) In: Chem. Phys. Lett. . 12, No. 2, December 1971, pp. 316-319. doi : 10.1016 / 0009-2614 (71) 85074-1 .
- ↑ A. Szemik-Hojniak, W.Rettig and I. Deperasinska: The forbidden emission of protonated proton sponge . In: Chem. Phys. Lett. . 343, No. 3, August 3, 2001, pp. 404-412. doi : 10.1016 / S0009-2614 (01) 00690-X .
- ↑ Sorokin, Vladimir I .: A Simple and Effective Procedure for the N -Permethylation of Amino-Substituted Naphthalenes . In: European Journal of Organic Chemistry . 2003, 2003, p. 496. doi : 10.1002 / ejoc.200390085 .
- ↑ Volker Raab, Ekaterina Gauchenova, Alexei Merkoulov, Klaus Harms, Jörg Sundermeyer, Borislav Kovačević and Zvonimir B. Maksić: 1,8-bis (hexamethyltriaminophosphazenyl) naphthalene, HMPN: A Superbasic Bisphosphazene “Proton Sponge” . In: J. Am. Chem. Soc. . 127, No. 45, 2005, pp. 15738-15743. doi : 10.1021 / ja052647v .