Practical synthesis of aromatic ethers by SNAr of fluorobenzenes with alkoxides

Tetrahedron Letters

Volumn 47, Issue 32, 2006, Pages 5661-5663

  Rodriguez, Juan R ^a   Agejas, Javier ^b   Bueno, Ana B ^b  

^a GalChimia   (Spain)

^b ELI LILLY AND COMPANY   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

AROMATIC COMPOUND; ETHER DERIVATIVE; FLUORINE DERIVATIVE; FLUOROBENZENE;

ARTICLE; SYNTHESIS;

EID: 33745757657     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2006.06.029     Document Type: Article

References (16)

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13. An improved method for the nucleophilic substitution of fluorobenzene by alcohols for the synthesis of resorcinols or catechols was published during the preparation of this manuscript:. Kim A., Powers J.D., and Toczko J.F. J. Org. Chem. 71 (2006) 2170-2172
14. **, with accurate SCF criteria and calculation of ESP-fit charges constrained by total charge and dipole moment. MO surfaces were also requested for orbitals between HOMO - 1 and LUMO + 1. Examination of the charges suggests that the explanation for the lower reactivity of the para-fluoro species is probably not electrostatic: the electrophilic carbon had a partial charge of 0.32, 0.54 and 0.48 in the ortho, meta and para isomers, respectively. On this basis, the ortho should have been the least reactive. A further possibility is that the para species is less reactive toward nucleophiles for the displacement of fluorine due to a lower orbital coefficient on the carbon atom to which the fluorine is attached in this molecule. The LUMO plots support this idea: the coefficient is near zero for both forms of the para-fluoroanisole studied, but is nonzero for both the other species in all conformations examined.
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