Borazine‐CF
<sub>3</sub>
<sup>−</sup>
Adducts for Rapid, Room Temperature, and Broad Scope Trifluoromethylation
作者:Jacob B. Geri、Michael M. Wade Wolfe、Nathaniel K. Szymczak
DOI:10.1002/anie.201711316
日期:2018.1.26
A fluoroform‐derived borazine CF3− transfer reagent is used to effect rapid nucleophilic reactions in the absence of additives, within minutes at 25 °C. Inorganic electrophiles spanning seven groups of the periodic table can be trifluoromethylated in high yield, including transition metals used for catalytic trifluoromethylation. Organic electrophiles included (hetero)arenes, enabling C−H and C−X
or I, Q = PPh4) in copper-mediatedtrifluoromethylation of arylhalides were studied. Qualitative and quantitative studies showed [Cu(CF3)2]−Q+ and [Cu(CF3)(I)]−Q+ were not highly reactive. Instead, a much more reactive species, ligandless [CuCF3] or DMF-ligated species [(DMF)CuCF3], was generated in the presence of excess CuI. On the basis of these results, a general mechanistic map for CuI-promoted
disorders in both structures. The crystals of complex 1b exist as a mixture of two species, [Cu(CF3)(Cl)]− and [Cu(CF3)2]−, while the crystals of complex 1c are a mixture of three species, [Cu(CF3)(I)]−, [Cu(CF3)2]−, and [CuI2]−. The structures of complexes 1b and 1c were tentatively assigned as [Cu(CF3)(Cl)]− and [Cu(CF3)(I)]−, since the unit-cell parameters of the crystal lattices of [Cu(CF3)2]− and [CuI2]−