Synthesis and Structural Studies of Pyridine-2-selenolates − Reactions with Electrophilic Phosphorus(III) Compounds and Related Complex Chemistry

C2-Symmetric P,N Ligands Derived from Carborane-Based Diphosphetanes: Synthesis and Coordination Chemistry

“…In contrast, in 11 and 12 , only the resonances for protons 3, 4, and 5 are shifted downfield (+0.06, +0.19, and +0.36 ppm in 11 ; +0.16, +0.26 and +0.18 ppm in 12 ), while the resonance for proton 2 is shifted upfield (−0.03 and −0.21 ppm in 11 and 12 , respectively). The shifts of 11 and 12 are similar for those observed in [{M­(μ-Br)­(C 5 H 4 N-2-SeP t Bu 2 )-κ N , P )} 2 ] (M = Cu, Ag) . Since hexafluorophosphate is a weakly coordinating anion and only one set of signals is observed for the pyridyl rings in 10 , the complex apparently adopts a C 2 -symmetric conformation also in solution.…”

C2-Symmetric P,N Ligands Derived from Carborane-Based Diphosphetanes: Synthesis and Coordination Chemistry

“…In contrast, in 11 and 12 , only the resonances for protons 3, 4, and 5 are shifted downfield (+0.06, +0.19, and +0.36 ppm in 11 ; +0.16, +0.26 and +0.18 ppm in 12 ), while the resonance for proton 2 is shifted upfield (−0.03 and −0.21 ppm in 11 and 12 , respectively). The shifts of 11 and 12 are similar for those observed in [{M­(μ-Br)­(C 5 H 4 N-2-SeP t Bu 2 )-κ N , P )} 2 ] (M = Cu, Ag) . Since hexafluorophosphate is a weakly coordinating anion and only one set of signals is observed for the pyridyl rings in 10 , the complex apparently adopts a C 2 -symmetric conformation also in solution.…”

C2-Symmetric P-Stereogenic Ferrocene Ligands with Heavier Chalcogenophosphinous Acid Ester Donor Sites

“…The tilt angles α showed values of 3.9(1)° at Fe1 and 5.8(1)° at Fe2 for both ferrocene units and indicated that almost no ring strain was present. The Au-P contacts between 2.305(10) Å and 2.337(9) Å were slightly longer than those observed in 7 but in the typical range for P-Au bond lengths [ 24 , 25 ]. For the solid-state structures of compounds 7 and 8 , no inter- or intramolecular Au···Au interactions were observed (Au···Au > 6.7 Å in 8 ).…”

2-Selenouridine, a Modified Nucleoside of Bacterial tRNAs, Its Reactivity in the Presence of Oxidizing and Reducing Reagents

“…Therefore, the course of oxidation of Se2U (1, 40 mM) (the 99.6% abundance of 77 Se present in 1 was documented by an extended ESI mass spectrum, Figure S3) in the presence of H 2 O 2 (20 mM), which was studied by 77 Se NMR in water at a temperature of 10 • C (Figure 5a, experiment #12). The resonance signal of δ 353 ppm in the spectrum of substrate (1) was attributed to the selone form (C=Se) of Se2U, according to the literature reports [50][51][52]. The addition of 0.5 equiv.…”

C2-Symmetric P,N Ligands Derived from Carborane-Based Diphosphetanes: Synthesis and Coordination Chemistry

“…In contrast, in 11 and 12 , only the resonances for protons 3, 4, and 5 are shifted downfield (+0.06, +0.19, and +0.36 ppm in 11 ; +0.16, +0.26 and +0.18 ppm in 12 ), while the resonance for proton 2 is shifted upfield (−0.03 and −0.21 ppm in 11 and 12 , respectively). The shifts of 11 and 12 are similar for those observed in [{M­(μ-Br)­(C 5 H 4 N-2-SeP t Bu 2 )-κ N , P )} 2 ] (M = Cu, Ag) . Since hexafluorophosphate is a weakly coordinating anion and only one set of signals is observed for the pyridyl rings in 10 , the complex apparently adopts a C 2 -symmetric conformation also in solution.…”

C2-Symmetric P-Stereogenic Ferrocene Ligands with Heavier Chalcogenophosphinous Acid Ester Donor Sites

“…The tilt angles α showed values of 3.9(1)° at Fe1 and 5.8(1)° at Fe2 for both ferrocene units and indicated that almost no ring strain was present. The Au-P contacts between 2.305(10) Å and 2.337(9) Å were slightly longer than those observed in 7 but in the typical range for P-Au bond lengths [ 24 , 25 ]. For the solid-state structures of compounds 7 and 8 , no inter- or intramolecular Au···Au interactions were observed (Au···Au > 6.7 Å in 8 ).…”

2-Selenouridine, a Modified Nucleoside of Bacterial tRNAs, Its Reactivity in the Presence of Oxidizing and Reducing Reagents

“…Therefore, the course of oxidation of Se2U (1, 40 mM) (the 99.6% abundance of 77 Se present in 1 was documented by an extended ESI mass spectrum, Figure S3) in the presence of H 2 O 2 (20 mM), which was studied by 77 Se NMR in water at a temperature of 10 • C (Figure 5a, experiment #12). The resonance signal of δ 353 ppm in the spectrum of substrate (1) was attributed to the selone form (C=Se) of Se2U, according to the literature reports [50][51][52]. The addition of 0.5 equiv.…”

C2-Symmetric P,N Ligands Derived from Carborane-Based Diphosphetanes: Synthesis and Coordination Chemistry

“…In contrast, in 11 and 12 , only the resonances for protons 3, 4, and 5 are shifted downfield (+0.06, +0.19, and +0.36 ppm in 11 ; +0.16, +0.26 and +0.18 ppm in 12 ), while the resonance for proton 2 is shifted upfield (−0.03 and −0.21 ppm in 11 and 12 , respectively). The shifts of 11 and 12 are similar for those observed in [{M­(μ-Br)­(C 5 H 4 N-2-SeP t Bu 2 )-κ N , P )} 2 ] (M = Cu, Ag) . Since hexafluorophosphate is a weakly coordinating anion and only one set of signals is observed for the pyridyl rings in 10 , the complex apparently adopts a C 2 -symmetric conformation also in solution.…”

C2-Symmetric P-Stereogenic Ferrocene Ligands with Heavier Chalcogenophosphinous Acid Ester Donor Sites

“…The tilt angles α showed values of 3.9(1)° at Fe1 and 5.8(1)° at Fe2 for both ferrocene units and indicated that almost no ring strain was present. The Au-P contacts between 2.305(10) Å and 2.337(9) Å were slightly longer than those observed in 7 but in the typical range for P-Au bond lengths [ 24 , 25 ]. For the solid-state structures of compounds 7 and 8 , no inter- or intramolecular Au···Au interactions were observed (Au···Au > 6.7 Å in 8 ).…”

2-Selenouridine, a Modified Nucleoside of Bacterial tRNAs, Its Reactivity in the Presence of Oxidizing and Reducing Reagents

“…Therefore, the course of oxidation of Se2U (1, 40 mM) (the 99.6% abundance of 77 Se present in 1 was documented by an extended ESI mass spectrum, Figure S3) in the presence of H 2 O 2 (20 mM), which was studied by 77 Se NMR in water at a temperature of 10 • C (Figure 5a, experiment #12). The resonance signal of δ 353 ppm in the spectrum of substrate (1) was attributed to the selone form (C=Se) of Se2U, according to the literature reports [50][51][52]. The addition of 0.5 equiv.…”