title: Extending the coordination chemistry of cobalt with the metalloligand [Pt₂(μ-S) ₂ (PPh₃)₄]: Synthesis of the first cobalt(III) derivatives

authors: Clarke, Hannah M.

subjects: Platinum complexes

abstract: The coordination chemistry of the metalloligand [Pt₂(μ-S) ₂ (PPh₃)₄] towards cobalt(II) and cobalt(III) centres has been explored using an electrospray ionisation mass spectrometry (ESI MS)-directed methodology. Reaction of [Pt₂(μ-S) ₂ (PPh₃)₄] with CoCl₂•6H₂O in methanol gave a green-yellow suspension of the known adduct [Pt₂(μ-S) ₂ (PPh₃)₄CoCl₂], and the CoBr₂ adduct could be similarly prepared. When in situ-generated [Pt₂(μ-S) ₂ (PPh₃)₄CoCl₂] is reacted with 8-hydroxyquinoline (HQ) and base, the initial product is the cobalt(II) adduct [Pt₂(μ-S)₂(PPh₃)₄CoQ]⁺, which is then converted in air to the cobalt(III) adduct [Pt₂(μ-S)₂(PPh₃)₄CoQ₂]⁺, isolated as its hexafluorophosphate salt. The corresponding picolinate (Pic) derivative [Pt₂(μ-S) ₂ (PPh₃)₄Co(Pic)₂]⁺ was similarly prepared, however reaction of [Pt₂(μ-S) ₂ (PPh₃)₄], CoCl₂•6H₂O and 8-(tosylamino)quinoline (HTQ) produced only the cobalt(II) adduct [Pt₂(μ-S)₂(PPh₃)₄CoTQ]⁺. Reactions of [Pt₂(μ-S)₂ (PPh₃)₄], CoCl₂•6H₂O and dithiocarbamates gave cobalt(III) complexes [Pt₂(μ-S)₂(PPh₃)₄Co(S₂CNR₂)₂]⁺ [R = Et or R₂ = (CH₂)₄], and proceeded much more rapidly, consistent with the known ability of the dithiocarbamate ligand to stabilize cobalt in higher oxidation states. A study of the fragmentation of cobalt(III) adducts by positive-ion ESI mass spectrometry indicated that [Pt₂(μ-S)₂(PPh₃)₄CoQ₂]⁺ fragments to form the radical cation [Pt₂(μ-S)₂(PPh₃)₄]⁺, which could also be generated by ESI MS analysis of [Pt₂(μ-S)₂(PPh₃)₄] in methanol–NaOH solution. In contrast, the corresponding indium(III) derivative [Pt₂(μ-S)₂(PPh₃)₄InQ₂]⁺, and the cobalt(III) dithiocarbamate [Pt₂(μ-S)₂(PPh₃)₄Co(S₂CN(CH₂)₄)₂]⁺ are much more reluctant to fragment under analogous conditions, and the differences are discussed in terms of cobalt(III) redox chemistry.

text: Extending the coordination chemistry of cobalt with the metalloligand [Pt₂(μ-S) ₂ (PPh₃)₄]: Synthesis of the first cobalt(III) derivatives The coordination chemistry of the metalloligand [Pt₂(μ-S) ₂ (PPh₃)₄] towards cobalt(II) and cobalt(III) centres has been explored using an electrospray ionisation mass spectrometry (ESI MS)-directed methodology. Reaction of [Pt₂(μ-S) ₂ (PPh₃)₄] with CoCl₂•6H₂O in methanol gave a green-yellow suspension of the known adduct [Pt₂(μ-S) ₂ (PPh₃)₄CoCl₂], and the CoBr₂ adduct could be similarly prepared. When in situ-generated [Pt₂(μ-S) ₂ (PPh₃)₄CoCl₂] is reacted with 8-hydroxyquinoline (HQ) and base, the initial product is the cobalt(II) adduct [Pt₂(μ-S)₂(PPh₃)₄CoQ]⁺, which is then converted in air to the cobalt(III) adduct [Pt₂(μ-S)₂(PPh₃)₄CoQ₂]⁺, isolated as its hexafluorophosphate salt. The corresponding picolinate (Pic) derivative [Pt₂(μ-S) ₂ (PPh₃)₄Co(Pic)₂]⁺ was similarly prepared, however reaction of [Pt₂(μ-S) ₂ (PPh₃)₄], CoCl₂•6H₂O and 8-(tosylamino)quinoline (HTQ) produced only the cobalt(II) adduct [Pt₂(μ-S)₂(PPh₃)₄CoTQ]⁺. Reactions of [Pt₂(μ-S)₂ (PPh₃)₄], CoCl₂•6H₂O and dithiocarbamates gave cobalt(III) complexes [Pt₂(μ-S)₂(PPh₃)₄Co(S₂CNR₂)₂]⁺ [R = Et or R₂ = (CH₂)₄], and proceeded much more rapidly, consistent with the known ability of the dithiocarbamate ligand to stabilize cobalt in higher oxidation states. A study of the fragmentation of cobalt(III) adducts by positive-ion ESI mass spectrometry indicated that [Pt₂(μ-S)₂(PPh₃)₄CoQ₂]⁺ fragments to form the radical cation [Pt₂(μ-S)₂(PPh₃)₄]⁺, which could also be generated by ESI MS analysis of [Pt₂(μ-S)₂(PPh₃)₄] in methanol–NaOH solution. In contrast, the corresponding indium(III) derivative [Pt₂(μ-S)₂(PPh₃)₄InQ₂]⁺, and the cobalt(III) dithiocarbamate [Pt₂(μ-S)₂(PPh₃)₄Co(S₂CN(CH₂)₄)₂]⁺ are much more reluctant to fragment under analogous conditions, and the differences are discussed in terms of cobalt(III) redox chemistry.

year: 2011

title: Vot Long Pati Ia! (Your vote, our
party)

authors: Goldsmith, Michael

subjects: Wan Smolbag Theatre

abstract: Review of the film "Vot Long Pati Ia!" The film is made by Wan Smolbag Theatre in Vanuatu and is a fascinating dramatization of political and developmental dilemmas in the South Pacific.

text: Vot Long Pati Ia! (Your vote, our
party) Review of the film "Vot Long Pati Ia!" The film is made by Wan Smolbag Theatre in Vanuatu and is a fascinating dramatization of political and developmental dilemmas in the South Pacific.

year: 2001

title: A Case for an Indigenous Court - a realisation of self-determination?

authors: Toki, Valmaine

subjects: Indigenous

abstract: This thesis searches for appropriate ways to alter entrenched patterns of highly negative outcomes for Māori in the criminal justice system. The statistics demonstrate that proportionately, Māori are much more likely to be apprehended, arrested, prosecuted, convicted and incarcerated than other New Zealanders and ethnic groups, and much less likely to be granted parole. 

An overview of the current relationship between Māori and the criminal justice system provides a background to begin understanding these long-standing patterns. An examination of the ancestral conceptions of tikanga Māori, including issues of proper conduct, punishment, behaviour and attaining balance, provides a persuasive framework to positively transform the criminal justice system. In order to understand why tikanga Māori is not meaningfully realised today, an historical review of the introduction of English law and legal systems clarifies the negative and almost fatal impact English law had on tikanga Māori. 

An evaluation of two instruments — Treaty of Waitangi and the United Nations Declaration on the Rights of Indigenous Peoples — provides further context for this dialogue. A specific focus on the right to culture and the right of self-determination, within these two documents, highlights the need to meaningfully revisit and/or realise these rights as a pathway to recognise the concepts of tikanga Māori. A review of comparative jurisdictions indicates existing support for the right to culture and the right of self-determination within respective legal systems and constitutions. 

An examination of the current criminal justice initiatives and policies in New Zealand highlights the status quo. This current status quo is set against initiatives in comparative jurisdictions. Following a domestic and international analysis, models underpinned by therapeutic jurisprudence and tikanga Māori, are suggested as a potential way forward for Māori to realise a form of self-determination.


In conclusion, new frameworks are proposed. These may provide an opportunity to apply the philosophy of Te Ao Māori, realised by an indigenous legal system, manifested by an indigenous court premised on fundamental Māori concepts and doctrine as the most promising way forward for Māori to ameliorate the disproportionate offending rates. A suggested extension to the Māori Land Court to include a criminal jurisdiction or, alternatively, a Tikanga Court is proposed.

text: A Case for an Indigenous Court - a realisation of self-determination? This thesis searches for appropriate ways to alter entrenched patterns of highly negative outcomes for Māori in the criminal justice system. The statistics demonstrate that proportionately, Māori are much more likely to be apprehended, arrested, prosecuted, convicted and incarcerated than other New Zealanders and ethnic groups, and much less likely to be granted parole. 

An overview of the current relationship between Māori and the criminal justice system provides a background to begin understanding these long-standing patterns. An examination of the ancestral conceptions of tikanga Māori, including issues of proper conduct, punishment, behaviour and attaining balance, provides a persuasive framework to positively transform the criminal justice system. In order to understand why tikanga Māori is not meaningfully realised today, an historical review of the introduction of English law and legal systems clarifies the negative and almost fatal impact English law had on tikanga Māori. 

An evaluation of two instruments — Treaty of Waitangi and the United Nations Declaration on the Rights of Indigenous Peoples — provides further context for this dialogue. A specific focus on the right to culture and the right of self-determination, within these two documents, highlights the need to meaningfully revisit and/or realise these rights as a pathway to recognise the concepts of tikanga Māori. A review of comparative jurisdictions indicates existing support for the right to culture and the right of self-determination within respective legal systems and constitutions. 

An examination of the current criminal justice initiatives and policies in New Zealand highlights the status quo. This current status quo is set against initiatives in comparative jurisdictions. Following a domestic and international analysis, models underpinned by therapeutic jurisprudence and tikanga Māori, are suggested as a potential way forward for Māori to realise a form of self-determination.


In conclusion, new frameworks are proposed. These may provide an opportunity to apply the philosophy of Te Ao Māori, realised by an indigenous legal system, manifested by an indigenous court premised on fundamental Māori concepts and doctrine as the most promising way forward for Māori to ameliorate the disproportionate offending rates. A suggested extension to the Māori Land Court to include a criminal jurisdiction or, alternatively, a Tikanga Court is proposed.

year: 2016