Hafnium(IV) and zirconium(IV) triflates as superior recyclable catalysts for the atom economic nitration of o-nitrotoluene

Tetrahedron Letters

Volumn 39, Issue 12, 1998, Pages 1641-1642

  Waller, Francis J ^a   Barrett, Anthony G M ^b   Braddock, D Christopher ^b   Ramprasad, Dorai ^a  

^a AIR PRODUCTS AND CHEMICALS INC   (United States)

^b IMPERIAL COLLEGE LONDON   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

HAFNIUM; TOLUENE DERIVATIVE; ZIRCONIUM;

ARTICLE; CATALYST; NITRATION;

EID: 0032546255     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)10861-9     Document Type: Article

References (13)

1. 3 see; (a) Marshmann, R. W. Aldrichimica Acta 1995, 28, 77.
2. (b) Kobayashi, S. Synlett 1994, 689.
3. (c) Engberts, J. B. N. F.; Feringa, B. L.; Keller, E.; Otto, S. Recl. Trav. Chim. Pays Bas 1996, 115, 457.
4. 2. Waller, F. J.; Barrett, A. G. M.; Braddock, D. C.; Ramprasad, D. Chem. Commun. 1997, 613.
5. 3. Hachiya, I.; Moriwaki, M.; Kobayshi, S. Tetrahedron Lett. 1995, 36, 409.
6. 4. Schmeißer, M.; Sartori, P.; Lippsmeier, B. Chem. Ber. 1970, 103, 868.
7. 5. (a) Kobayashi, S.; Moriwaki, M.; Hachiya, I. Bull. Chem. Soc. Jpn. 1997, 70, 267.
8. (b) Kobayashi, S.; Moriwaki, M.; Hachiya, I. Tetrahedron Lett. 1996, 37, 2053.
9. 6. Hachiya, I.; Moriwaki, M.; Kobayashi, S. Bull. Chem. Soc. Jpn. 1995, 68, 2053.
10. -1.
11. 8. Typically a liquid-liquid two-phase system is obtained where the catalyst is solubilised in the 69% nitric acid and a less dense organic phase comprising the substrate and solvent (1,2-dichloroethane).
12. 4) and evaporated to give dinitrotoluenes (502 mg, 92%). The pale yellow aqueous phase was evaporated to give hafnium(IV) triflate as a deliquescent off-white solid (385 mg, 98%).
13. 10. When Hafnium(IV) triflate was recycled and re-used for the nitration of o-nitrotoluene, an 87% conversion to DNT's was obtained after 24h.