Experimental and Theoretical Investigations of Tellurium(IV) Methanediides and Their Insertion Products with Sulfur and Iodine

The reactions of Li₂[C­(Ph₂PS)₂] with tellurium tetrahalides in a 1:1 molar ratio in toluene afford the complexes {TeX₂[C­(Ph₂PS)₂]}₂ (<b>7a</b>, X = Cl; <b>7b</b>, X = Br; <b>7c</b>, X = I). These complexes dimerize through halide bridges in the solid state, and the tridentate ligand is <i>S,C,S-</i>coordinated to the tellurium center with a Te–C bond length of 2.024(3), 2.030(6), and 2.045(8) Å, respectively. In the case of TeBr₄, small amounts of the complex TeX₂[SC­(Ph₂PS)₂] (<b>8b</b>, X = Br) were isolated and shown by X-ray analysis to be the result of formal sulfur insertion into the Te–C bond of <b>7b</b>. Complex <b>8b</b> and the corresponding dichloride and diiodide, <b>8a</b> (X = Cl) and <b>8c</b> (X = I), may be prepared in good yields by the metathetical reactions of Li₂[SC­(Ph₂PS)₂] with TeX₄ in toluene. The complex TeI₂[(I₂)­C­(Ph₂PS)₂] (<b>9</b>) was isolated as a minor product from the reaction of Li₂[C­(Ph₂PS)₂] and TeI₄ and identified by X-ray crystallography. Complex <b>9</b> is constructed from the insertion of an iodine atom of an I₂ molecule into the Te–C bond of <b>7c</b>, resulting in a T-shaped geometry at that iodine atom and an almost linear Te–I–I unit with an elongated I–I bond; the C–I bond length is typical for a C­(sp³)–I bond. DFT calculations supplemented with Hirshfeld charge analysis, Boys–Foster localization of molecular orbitals, and evaluation of the electron localization functions indicate that in these species the ligand engages predominantly in σ bonding through the lone pairs on the carbon and sulfur atoms. The latter atoms participate in three-center interactions with tellurium. The bonds between the heavy elements and carbon are strongly polarized, and the character of the latter atom ranges from sp² to sp³

Reversibly Trapping Visible Laser Light through the Catalytic Photo-oxidation of I^– by Ru(bpy)₃²⁺

A Gaussian, visible laser beam traveling in a hydrogel doped with NaI and Ru­(bpy)₃Cl₂ spontaneously transforms into a localized, self-trapped beam, which propagates without diverging through the medium. The catalytic, laser-light-induced oxidation of I^– by [Ru­(bpy)₃]²⁺ generates I₃^– species, which create a refractive index increase along the beam path. The result is a cylindrical waveguide, which traps the optical field as bound modes and suppresses natural diffraction. When the beam is switched off, diffusion of I₃^– erases the waveguide within minutes and the system reverts to its original composition, enabling regeneration of the self-trapped beam. Our findings demonstrate reversible self-trapping for the first time in a precisely controllable, molecular-level photoreaction and could open routes to circuitry-free photonics devices powered by the interactions of switchable self-trapped beams

Reversibly Trapping Visible Laser Light through the Catalytic Photo-oxidation of I^– by Ru(bpy)₃²⁺

A Gaussian, visible laser beam traveling in a hydrogel doped with NaI and Ru­(bpy)₃Cl₂ spontaneously transforms into a localized, self-trapped beam, which propagates without diverging through the medium. The catalytic, laser-light-induced oxidation of I^– by [Ru­(bpy)₃]²⁺ generates I₃^– species, which create a refractive index increase along the beam path. The result is a cylindrical waveguide, which traps the optical field as bound modes and suppresses natural diffraction. When the beam is switched off, diffusion of I₃^– erases the waveguide within minutes and the system reverts to its original composition, enabling regeneration of the self-trapped beam. Our findings demonstrate reversible self-trapping for the first time in a precisely controllable, molecular-level photoreaction and could open routes to circuitry-free photonics devices powered by the interactions of switchable self-trapped beams

Reversibly Trapping Visible Laser Light through the Catalytic Photo-oxidation of I^– by Ru(bpy)₃²⁺

A Gaussian, visible laser beam traveling in a hydrogel doped with NaI and Ru­(bpy)₃Cl₂ spontaneously transforms into a localized, self-trapped beam, which propagates without diverging through the medium. The catalytic, laser-light-induced oxidation of I^– by [Ru­(bpy)₃]²⁺ generates I₃^– species, which create a refractive index increase along the beam path. The result is a cylindrical waveguide, which traps the optical field as bound modes and suppresses natural diffraction. When the beam is switched off, diffusion of I₃^– erases the waveguide within minutes and the system reverts to its original composition, enabling regeneration of the self-trapped beam. Our findings demonstrate reversible self-trapping for the first time in a precisely controllable, molecular-level photoreaction and could open routes to circuitry-free photonics devices powered by the interactions of switchable self-trapped beams

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization

Sterically Directed Functionalization of the Redox-Active Bis(imino)acenaphthene Ligand Class: An Experimental and Theoretical Investigation

The synthesis, characterization, and theoretical study of the sterically directed functionalization of the redox-active bis­(imino)­acenaphthene (BIAN) ligand class has been explored. With dependence on the steric congestion encompassing the N–C–C–N fragment of the Ar-BIAN ligand, functionalization can be directed to proceed either via a radical backbone dearomatization or a nucleophilic imine C-alkylation pathway. The structures of the Ar-BIAN derivatives <b>14</b>–<b>19</b> were determined by means of single-crystal X-ray diffraction. The reaction pathways involved in Ar-BIAN functionalization were monitored by means of EPR spectroscopy. The experimental results and observations were examined in conjunction with DFT-D calculations in order to explain the driving forces that direct the pathways leading to Ar-BIAN functionalization