High-boron-content porphyrin-cored aryl ether dendrimers: controlled synthesis, characterization, and photophysical properties.
The synthesis and characterization of a set of poly(aryl ether) dendrimers with tetraphenylporphyrin as the core and 4, 8, 16, or 32 closo-carborane clusters are described. A regioselective hydrosilylation reaction on the allyl-terminated functions with carboranylsilanes in the presence of Karstedt's catalyst leads to different generations of boron-enriched dendrimers. This versatile approach allows the incorporation of a large number of boron atoms in the dendrimers' periphery. Translational diffusion coefficients (D) determined by DOSY NMR experiments permit estimation of the hydrodynamic radius (RH) and molecular size for each dendrimer. Furthermore, a notable correlation between D and the molecular weight (MW) is found and can be used to predict their overall size and folding properties. The UV-vis and emission behavior are not largely affected by the functionalization, therefore implying that the presence of carboranes does not alter their photoluminescence properties.
†Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
Justo
J
Cabrera-González
§Facultad de Química, Departamento de Química Orgánica, Universidad Nacional Autónoma de México (UNAM), 04510 México D.F., México.
Elba
E
Xochitiotzi-Flores
†Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
Clara
C
Viñas
†Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
Francesc
F
Teixidor
§Facultad de Química, Departamento de Química Orgánica, Universidad Nacional Autónoma de México (UNAM), 04510 México D.F., México.
Héctor
H
García-Ortega
§Facultad de Química, Departamento de Química Orgánica, Universidad Nacional Autónoma de México (UNAM), 04510 México D.F., México.
Norberto
N
Farfán
⊥Departamento de Química, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, 07000 México D.F., México.
Rosa
R
Santillan
∥Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona (UAB), E-08193 Bellaterra, Barcelona, Spain.
Teodor
T
Parella
†Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain.
Rosario
R
Núñez