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Title: Photodriven Elimination of Chlorine From Germanium and Platinum in a Dinuclear Pt II →Ge IV Complex
Abstract

Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph2P)C6H4)2GeIVCl2]PtIICl2and [(o‐(Ph2P)C6H4)2ClGeIII]PtIIICl3, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph2P)C6H4)2ClGeIII]PtICl with quantum yields of 1.7 % and 3.2 % for the GeIV–PtIIand GeIII–PtIIIisomers, respectively. Conversion of the GeIV–PtIIisomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the GeIII–PtIIIisomer point to a ligand arene–Cl.charge‐transfer complex as an intermediate.

 
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PAR ID:
10304758
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
133
Issue:
41
ISSN:
0044-8249
Page Range / eLocation ID:
p. 22526-22532
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Abstract

    Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph2P)C6H4)2GeIVCl2]PtIICl2and [(o‐(Ph2P)C6H4)2ClGeIII]PtIIICl3, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph2P)C6H4)2ClGeIII]PtICl with quantum yields of 1.7 % and 3.2 % for the GeIV–PtIIand GeIII–PtIIIisomers, respectively. Conversion of the GeIV–PtIIisomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the GeIII–PtIIIisomer point to a ligand arene–Cl.charge‐transfer complex as an intermediate.

     
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  2. ABSTRACT Rationale

    These experiments were conducted to measure the diversity of organo‐U (IV) and U (III) ions created using multiple‐stage tandem MS and collision‐induced dissociation of halogen‐substituted UVIO2‐phenide complexes [UO2(C6H3FX)]+, X = Cl, Br, or I.

    Methods

    Samples of UO2(O2C‐C6H3FX)2were prepared by digesting UO3with appropriate halogen‐substituted carboxylic acids in deionized water. Solutions for ESI were created by diluting the digested sample in 50:50 H2O/CH3OH. Precursor ions for multiple‐stage tandem MS were generated by electrospray ionization (ESI). Multiple‐stage collision‐induced dissociation (He collision gas) in a linear quadrupole ion trap mass spectrometer was used to prepare species such as [UIVFX(C≡CH)]+and UIIIF(C≡CH)]+for subsequent study of ion‐molecule reactions with adventitious neutrals in the ion trap.

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    Multiple‐stage CID of the [UO2(C6H3FX)]+, X = Cl, Br, or I, complexes caused removal of both “yl” oxo ligands from of the UO22+moiety to create ions such as [UIVFX(C≡CH)]+and [UIIIFX]+. For [UIVFXC≡CH]+and [UIIIFC≡CH]+products, hydrolysis to generate [UIVFX (OH)]+and [UIIIF (OH)]+, with concomitant loss of HC≡CH, was observed. CID of [UO2(C6H3FBr)]+and [UO2(C6H3FI)]+caused reductive elimination of the respective halogen radicals to generate interesting organo‐U (III) species such as [UIIIF(C≡CH)]+and [UIIIC2]+.

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