Acid Activation in Phenyliodine Dicarboxylates: Direct Observation, Structures, and Implications.
The use of the hypervalent iodine reagents in oxidative processes has become a staple in modern organic synthesis. Frequently, the reactivity of λ3iodanes is further enhanced by acids (Lewis or Brønsted). The origin of such activation, however, has remained elusive. Here, we use the common combination of PhI(OAc)2with BF3·Et2O as a model to fully explore this activation phenomenon. In addition to the spectroscopic assessment of the dynamic acid-base interaction, for the first time the putative PIDA·BF3complex has been isolated and its structure determined by X-ray diffraction. Consequences of such activation are discussed from a structural and electronic (DFT) points of views, including the origins of the enhanced reactivity.
Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology , 43007, Tarragona, Spain.
Susana
S
Izquierdo
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Stéphanie
S
Essafi
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Iker
I
Del Rosal
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Pietro
P
Vidossich
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Roser
R
Pleixats
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Adelina
A
Vallribera
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Gregori
G
Ujaque
Departament de Química and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universitat Autònoma de Barcelona , 08193 Cerdanyola del Vallès, Spain.
Agustí
A
Lledós
Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology , 43007, Tarragona, Spain.
Alexandr
A
Shafir