近年來由于對環境保護越來越重視，一類新的硝化方法發展了起來。這種方法用鑭系金屬 lanthanide(III)或 IV 族金屬的三氟磺酸鹽 [Ln(OTf)₃, Ln=La-Lu; M(OTf) ₄, M= Hf, Zr] 以及 tris(trifluoromethanesulphonyl)methides("triflides") [M(CTf₃) ₃; M=Yb, Sc] 作催化劑【a. Waller, F. J.;Barrett, A. G. M.; Braddock, D. C.; Ramprasad, D. Chem. Commun. 1997,613. b. For an interesting report utilizing La(NO3)3/HCl/NaNO3 for thenitration of phenols see: Ouertani, M.; Girard, P.; Kagan, H. B. TetrahedronLett. 1982, 23, 4315. c. Waller, F. J.; Barrett, A. G. M.;Braddock, D. C.; Ramprasad, D. Tetrahedron Lett. 1998, 39,1641.】，催化等當量的硝酸（69％）硝化苯環，這種方法對一般的苯環及一些鈍化的苯環都能得到高產率。由于只用等當量的硝酸，所以副產物僅僅是水，沒有廢酸產生，而且催化劑可以回收，并經過簡單處理后反復使用。因此這種方法是較為環保的一種方法。

Nitric acid (69%; 274 mg, 3.0 mmol) was added to a stirredsuspension of ytterbium(III) triflate (186 mg, 0.30 mmol) in 1,2-dichloroethane(5 mL). The suspension dissolved to give a two phase system in which theaqueous phase was the more dense.  Toluene(270 mg, 3.0 mmol) was added and the stirredmixture was heated at reflux for 12 h.  Duringthe reaction a white solid precipitated and the organic phase became yellow,and after 12 h no phase boundary was apparent.  The solution was allowed to cool and dilutedwith water. The yellow organic phase was dried (MgSO₄) and evaporated to give nitrotoluene (390 mg, 95%). Thecolourless aqueous phase was evaporated to give ytterbium(III) triflate as a whitefree-flowing solid (183 mg, 98%).

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