Protonation studies of electrophilic platinum(II) alkyl complexes: synthesis and characterization of (dfepe)Pt(Me)X (X = O2CCF3, OSO2CF3, OSO3H)

Activation of Aromatic C−H Bonds by (dmpe)Pt(Me)X (X = Me, O2CCF3, OTf) Systems

“…The sensitivity of 1 J P tP coupling constants to trans ligand donor abilities is well established and is reflected in the progressively higher trans -P coupling values observed for X = Cl (3930 Hz), O 2 CCF 3 (4111 Hz), and OTf (4572 Hz), consistent with the relative anion donor abilities Cl - > O 2 CCF 3 - > OTf - in this system. The significant difference between the 1 J P tP value found for 6 in CD 2 Cl 2 (4572 Hz) and that previously reported in acetone (4305 Hz) 13a is similar in magnitude to differences observed for (dfepe)Pt(Me)X systems, and indicates that solvation to form [(dmpe)Pt(Me)(acetone)] + OTf - in this solvent is probably occurring …”

Activation of Aromatic C−H Bonds by (dmpe)Pt(Me)X (X = Me, O2CCF3, OTf) Systems

“…The sensitivity of 1 J P tP coupling constants to trans ligand donor abilities is well established and is reflected in the progressively higher trans -P coupling values observed for X = Cl (3930 Hz), O 2 CCF 3 (4111 Hz), and OTf (4572 Hz), consistent with the relative anion donor abilities Cl - > O 2 CCF 3 - > OTf - in this system. The significant difference between the 1 J P tP value found for 6 in CD 2 Cl 2 (4572 Hz) and that previously reported in acetone (4305 Hz) 13a is similar in magnitude to differences observed for (dfepe)Pt(Me)X systems, and indicates that solvation to form [(dmpe)Pt(Me)(acetone)] + OTf - in this solvent is probably occurring …”

Synthesis and Reactivity of [(C2F5)2MeP]2Pt(Me)X (X = Me, O2CCF3, OTf, OSO2F): A Reactivity Comparison with Chelate Acceptor Analogues

“…Solution IR data in chloroform reveal a single ν(CO) band at 2101 cm -1 . This stretching frequency is lower than that observed for the cationic platinum complex (dfepe)Pt(Me)(CO) + (2174 cm -1 ),4d but actually higher than the average ν(CO) value reported for cis -(CO) 2 Pt(Me) 2 (2089 cm -1 ) . This comparison lends further support to our assertion that the electronic influence of dfmp and related perfluoroalkylphosphines is very similar to CO. A variable CO pressure NMR study was performed with cis -(dfmp) 2 Pt(Me) 2 : under 100 psi CO in C 6 D 6 , a mixture of 4 , free dfmp, and cis -(CO) 2 PtMe 2 was observed after 40 min.…”

“…First-order plots (Figure ) gave a first-order rate constant in HOTf of 1.28(2) × 10 -6 s -1 , a value that is 80 times slower than the protonolysis rate for (dfepe)Pt(Me)(OTf) under these conditions. The protonolysis rate obtained for trans -(dfmp) 2 Pt(Me)(OTf) in DOTf (4.67(4) × 10 -7 s -1 ) gave a kinetic isotope effect of 2.7, which is identical to the observed k H / k D value found for (dfepe)Pt(Me)(OTf) at 100 °C 4b…”

Synthesis and Structural Characterization of an Unusual Platinum π-Arene Complex: (η 6 -C 6 H 3 Me 3 )Pt[(C 2 F 5 ) 2 PMe]Me +Thapaliya1, Debnath2, Arulsamy3 et al. 2015OrganometallicsSelf Cite

“…This bonding asymmetry is not correlated with any significant C­(aryl)–C­(aryl) bond alternation (1.394(4)–1.421(4) Å) or with trans influence effects of the dfmp and methyl ligands, but may be indicative of facile ring slippage and arene exchange/dissociation, as has been noted for similar palladium and nickel systems. , The short Pt–P bond distance of 2.1620(7) Å is in keeping with the generally observed trend for PFAP complexes . Relative to other structurally characterized Pt­(II)–PFAP systems, this bond distance falls within the range 2.135–2.186 Å found for Pt­(II)–PFAP with weak trans influence groups such as trifluoroacetate, , triflate, pentafluoropyridine, and fluoroarsenate as well as antimonate anions, suggesting that the effective trans influence of the π-arene ligand in complex 1 is low.…”

Activation of Aromatic C−H Bonds by (dmpe)Pt(Me)X (X = Me, O2CCF3, OTf) Systems

“…The sensitivity of 1 J P tP coupling constants to trans ligand donor abilities is well established and is reflected in the progressively higher trans -P coupling values observed for X = Cl (3930 Hz), O 2 CCF 3 (4111 Hz), and OTf (4572 Hz), consistent with the relative anion donor abilities Cl - > O 2 CCF 3 - > OTf - in this system. The significant difference between the 1 J P tP value found for 6 in CD 2 Cl 2 (4572 Hz) and that previously reported in acetone (4305 Hz) 13a is similar in magnitude to differences observed for (dfepe)Pt(Me)X systems, and indicates that solvation to form [(dmpe)Pt(Me)(acetone)] + OTf - in this solvent is probably occurring …”

Synthesis and Reactivity of [(C2F5)2MeP]2Pt(Me)X (X = Me, O2CCF3, OTf, OSO2F): A Reactivity Comparison with Chelate Acceptor Analogues

“…Solution IR data in chloroform reveal a single ν(CO) band at 2101 cm -1 . This stretching frequency is lower than that observed for the cationic platinum complex (dfepe)Pt(Me)(CO) + (2174 cm -1 ),4d but actually higher than the average ν(CO) value reported for cis -(CO) 2 Pt(Me) 2 (2089 cm -1 ) . This comparison lends further support to our assertion that the electronic influence of dfmp and related perfluoroalkylphosphines is very similar to CO. A variable CO pressure NMR study was performed with cis -(dfmp) 2 Pt(Me) 2 : under 100 psi CO in C 6 D 6 , a mixture of 4 , free dfmp, and cis -(CO) 2 PtMe 2 was observed after 40 min.…”

“…First-order plots (Figure ) gave a first-order rate constant in HOTf of 1.28(2) × 10 -6 s -1 , a value that is 80 times slower than the protonolysis rate for (dfepe)Pt(Me)(OTf) under these conditions. The protonolysis rate obtained for trans -(dfmp) 2 Pt(Me)(OTf) in DOTf (4.67(4) × 10 -7 s -1 ) gave a kinetic isotope effect of 2.7, which is identical to the observed k H / k D value found for (dfepe)Pt(Me)(OTf) at 100 °C 4b…”

Synthesis and Structural Characterization of an Unusual Platinum π-Arene Complex: (η 6 -C 6 H 3 Me 3 )Pt[(C 2 F 5 ) 2 PMe]Me +Thapaliya1, Debnath2, Arulsamy3 et al. 2015OrganometallicsSelf Cite

“…This bonding asymmetry is not correlated with any significant C­(aryl)–C­(aryl) bond alternation (1.394(4)–1.421(4) Å) or with trans influence effects of the dfmp and methyl ligands, but may be indicative of facile ring slippage and arene exchange/dissociation, as has been noted for similar palladium and nickel systems. , The short Pt–P bond distance of 2.1620(7) Å is in keeping with the generally observed trend for PFAP complexes . Relative to other structurally characterized Pt­(II)–PFAP systems, this bond distance falls within the range 2.135–2.186 Å found for Pt­(II)–PFAP with weak trans influence groups such as trifluoroacetate, , triflate, pentafluoropyridine, and fluoroarsenate as well as antimonate anions, suggesting that the effective trans influence of the π-arene ligand in complex 1 is low.…”

Activation of Aromatic C−H Bonds by (dmpe)Pt(Me)X (X = Me, O2CCF3, OTf) Systems

“…The sensitivity of 1 J P tP coupling constants to trans ligand donor abilities is well established and is reflected in the progressively higher trans -P coupling values observed for X = Cl (3930 Hz), O 2 CCF 3 (4111 Hz), and OTf (4572 Hz), consistent with the relative anion donor abilities Cl - > O 2 CCF 3 - > OTf - in this system. The significant difference between the 1 J P tP value found for 6 in CD 2 Cl 2 (4572 Hz) and that previously reported in acetone (4305 Hz) 13a is similar in magnitude to differences observed for (dfepe)Pt(Me)X systems, and indicates that solvation to form [(dmpe)Pt(Me)(acetone)] + OTf - in this solvent is probably occurring …”

Synthesis and Reactivity of [(C2F5)2MeP]2Pt(Me)X (X = Me, O2CCF3, OTf, OSO2F): A Reactivity Comparison with Chelate Acceptor Analogues

“…Solution IR data in chloroform reveal a single ν(CO) band at 2101 cm -1 . This stretching frequency is lower than that observed for the cationic platinum complex (dfepe)Pt(Me)(CO) + (2174 cm -1 ),4d but actually higher than the average ν(CO) value reported for cis -(CO) 2 Pt(Me) 2 (2089 cm -1 ) . This comparison lends further support to our assertion that the electronic influence of dfmp and related perfluoroalkylphosphines is very similar to CO. A variable CO pressure NMR study was performed with cis -(dfmp) 2 Pt(Me) 2 : under 100 psi CO in C 6 D 6 , a mixture of 4 , free dfmp, and cis -(CO) 2 PtMe 2 was observed after 40 min.…”

“…First-order plots (Figure ) gave a first-order rate constant in HOTf of 1.28(2) × 10 -6 s -1 , a value that is 80 times slower than the protonolysis rate for (dfepe)Pt(Me)(OTf) under these conditions. The protonolysis rate obtained for trans -(dfmp) 2 Pt(Me)(OTf) in DOTf (4.67(4) × 10 -7 s -1 ) gave a kinetic isotope effect of 2.7, which is identical to the observed k H / k D value found for (dfepe)Pt(Me)(OTf) at 100 °C 4b…”

Synthesis and Structural Characterization of an Unusual Platinum π-Arene Complex: (η 6 -C 6 H 3 Me 3 )Pt[(C 2 F 5 ) 2 PMe]Me +Thapaliya1, Debnath2, Arulsamy3 et al. 2015OrganometallicsSelf Cite

“…This bonding asymmetry is not correlated with any significant C­(aryl)–C­(aryl) bond alternation (1.394(4)–1.421(4) Å) or with trans influence effects of the dfmp and methyl ligands, but may be indicative of facile ring slippage and arene exchange/dissociation, as has been noted for similar palladium and nickel systems. , The short Pt–P bond distance of 2.1620(7) Å is in keeping with the generally observed trend for PFAP complexes . Relative to other structurally characterized Pt­(II)–PFAP systems, this bond distance falls within the range 2.135–2.186 Å found for Pt­(II)–PFAP with weak trans influence groups such as trifluoroacetate, , triflate, pentafluoropyridine, and fluoroarsenate as well as antimonate anions, suggesting that the effective trans influence of the π-arene ligand in complex 1 is low.…”