1579984-49-8Relevant articles and documents
Characterization and phenylacetylene-assisted cyclometalation of an isolable hydrido-selenolato PtII complex having phosphite ligands, cis-[PtH(SeTrip){P(OPh)3}2]#
Kamon, Hitomi,Aoki, Yutaro,Nakata, Norio,Ishii, Akihiko
, p. 274 - 282 (2014/03/21)
A hydridoselenolato PtII complex having P(OPh)3 ligands, cis-[PtH(SeTrip){P(OPh)3}2] (Trip: 9-triptycyl), was synthesized by the reaction of TripSeH with [Pt{P(OPh)3} 2]. The structure was characterized by NMR spectroscopy and X-ray crystallography in comparison with the corresponding PPh3 complex, cis-[PtH(SeTrip)(PPh3)2], indicating the stronger coordination of P(OPh)3 to the Pt center than that of PPh 3. On heating at 130 °C in xylene for 17 h, cis-[PtH(SeTrip)- {P(OPh)3}2] was converted to the corresponding 1,2-selenaplatinacycle (SP-42)-[Pt(kC1,kSe9-TripSe(2-)) {P(OPh)3}2] through an intramolecular cyclization (cyclometalation). The reaction with dimethyl acetylenedicarboxylate (DMAD) gave a mixture of hydroselenation products (E)- and (Z)-(MeO2C)CH= C(SeTrip)CO2Me non-stereoselectively together with 1H-2-benzoselenin, dimethyl 7H-7,11b[1',2']-benzenoanthra[9,1-bc]selenin-2,3-dicarboxylate. In the reaction with phenylacetylene in toluene at 110 °C, phenylacetylene served as a hydrogen acceptor to form the 1,2-selenaplatinacycle and styrene. Based on the results of controlled experiments using cis-[PtD(SeTrip){P(OPh) 3}2] and phenylacetylene-d, the mechanism of the cyclometalation was proposed as the 1,2- (major) and 2,1- (minor) insertions of phenylacetylene into the Pt-H bond followed by cyclometalation between the Pt center and the triptycyl group. The reaction with phenylacetylene in the presence of excess P(OPh)3 furnished a 1,2,3-oxaphosphaplatinacycle, (SP-4-2)-[Pt{kC,kP-(Z)-CH=C(Ph)-OP(OPh)2}(SeTrip){P(OPh) 3}], as a minor product, together with the 1,2-selenaplatinacycle in a decreased yield.
