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.
Cyclometalation of 2-vinylpyridine with MCl(2)(PPh(3))(3) and MHCl(PPh(3))(3) (M = Ru, Os)
Treatment of RuCl2(PPh3)3 in benzene at room temperature with 2-vinylpyridine produces the vinylpyridine complex RuCl2(2-CH2CHC5H4N)(PPh3)2. In the presence of Cs2CO3, RuCl2(PPh3)3 reacts with 2-vinylpyridine at room temperature to give the cyclometalated complex RuCl(CHCHC5H4N)(CH2CHC5H4N)(PPh3), which is also produced from the reaction of RuHCl(PPh3)3 with 2-vinylpyridine. OsCl2(PPh3)3 reacts with 2-vinylpyridine/Cs2CO3 at room temperature to give the analogous cyclometalated complex OsCl(CHCHC5H4N)(CH2CHC5H4N)(PPh3). In the presence of NaBF4, the reaction produces [Os(CHCHC5H4N)(CH2CHC5H4N)(PPh3)2]BF4. The dihydrogen complex Os(H2)Cl(CHCHC5H4N)(PPh3)2 is produced from the reaction of OsHCl(PPh3)3 with 2-vinylpyridine. The mechanism of the cyclometalation reactions has been investigated by computational chemistry.
Agostic interactions in transition metal compounds
The impact of agostic interactions (i.e., 3-center–2-electron MHC bonds) on the structures and reactivity of organotransition metal compounds is reviewed.