Thermal reaction of a (hydrido)(selenolato)platinum(II) complex having a dibenzobarrelenyl group leading to three cyclometalations.
The thermal reaction of a (dibenzobarreleneselenolato)(hydrido)platinum(ii) complex gave two four-membered selenaplatinacycles, one of which is formed by hydroplatination of the Pt-H bond to the etheno bridge and the other is a vinylic C-H bond activation product, and a five-membered selenaplatinacycle formed by an aromatic C-H bond activation.
Fluorescent 3-methylene-2,3-dihydrochalcogenophenes incorporated in a rigid dibenzobarrelene skeleton.
The fluorescent 3-methylene-2,3-dihydroselenophene derivative (Φ(F) = 0.86 in CH(2)Cl(2)) incorporated in a dibenzobarrelene skeleton was synthesized by the reaction of a four-membered selenaplatinacycle with dimethyl acetylenedicarboxylate (DMAD) or reaction of bis(dibenzobarrelenyl) diselenide with DMAD in the presence of Pd(PPh(3))(4) and PPh(3). A fluorescent sulfur homologue (Φ(F) = 1.0 in CH(2)Cl(2)) was also synthesized by the reaction of bis(dibenzobarrelenyl) disulfide with DMAD in the presence of Pd(PPh(3))(4). Selected chemical transformations of these diesters were also investigated.
Platinum(IV) complexes : C-H activation at low temperatures
The oxidation of square-planar cyclometalated Pt(II) phenylpyridine species using the electrophilic chlorine based oxidant PhICl2 has been studied. Rapid oxidations are observed in chloroform solvent at -40 degrees C leading to single products. In acetone solvent isomeric forms of the product are formed, and these are observed to isomerize at around -10 degrees C. The oxidation of a complex with an uncyclometalated pendant arm resulted in the very rapid cyclometalation of that arm by the resulting electrophilic Pt(IV) species.