ABSTRACT
Winding vine-shaped molecular asymmetry is induced by enantioselective ring-closing metathesis with a chiral molybdenum catalyst. The reaction proceeds under mild conditions through an E-selective ring-closing metathesis leading to macrocyclic bisazoles with enantioselectivities of up to 96% ee.
ABSTRACT
The coupling of TiO(2) and transition metal complexes is attempted with the aim of higher functionalization of the TiO(2) photocatalyst. UV irradiation (lambda(ex)>300 nm) of a TiO(2) suspension containing equimolar aqueous solutions of FeCl(3) and K(3)[Fe(CN)(6)] forms uniform thin films of "water-insoluble Prussian blue" (PB, Fe(4)(3+) [Fe(II)(CN)(6)](3)) on the surface of TiO(2) particles. The PB photodeposition is enhanced significantly by the addition of a small amount of CH(3)OH in both the rutile and anatase TiO(2) systems. The activity of anatase TiO(2) is greater than that of rutile in the presence of CH(3)OH (2.46 M) by a factor of 1.6+/-0.2, whereas the activities are comparable in the absence of CH(3)OH. These results are discussed on the basis of a proposed reaction mechanism. Copyright 2001 Academic Press.