title: Reactions of cyclomanganated compounds

authors: Mace, Wade

abstract: This thesis describes novel reactions of cyclomanganated compounds of the general form shown below. The ligand is bonded by a metal-carbon σ-bond, with X acting as a donor atom to form the chelate ring. The organic ligands were derived from aryl and heteroaryl ketones, chalcones, dienones and azabutadienes. 
A preliminary investigation has previously been undertaken into the reaction of carbon disulfide with some orthomanganated aryl ketones. In the present study these reactions were further investigated, with the isolation of new η2-S, S-dithiocarboxylate complexes, e.g. 46. In other cases the reaction of carbon disulfide with cyclomanganated compounds afforded the novel Mn4 species 50 in low yield. 
The reactions of orthomanganated acetyl-aryl compounds with organic isocyanides (C≡NR) afforded a number of novel compounds. For example η2-(2-acetylphenyl)-tetracarbonylmanganese (79) afforded four different types of products depending on the isocyanide; tert-butyl isocyanide produced 82, ethyl isocyanide produced 95 and 96, and 4-methoxyphenyl isocyanide produced 98 and 99. 
With orthomanganated 2-acetylthiophene, CNBut gave the quinone species 88 and 89,which showed high anti fungal and antitumor activity. 
Cyclomanganated dienones (e.g. 127) were previously known to react with alkynes to give either (η5-pyranyl)Mn(CO)3 (e.g. 130) or (η5-oxocycloheptadienyl)Mn(C0)3 (e.g.129) products. The factors influencing which product is formed were more systematically investigated and a deuterium-labelling experiment was used to probe the1,2-phenyl shift that occurs for the (η5-oxocycloheptadienyl)Mn(C0)3 products . 
A preliminary investigation of the reactions of 4-phenyl-1-(4-tolyl)-l-azabuta-1, 3-diene(TAD) with PhCH2Mn(CO)5 and unsaturated substrates including phenyl acetylene, methyl acrylate, PhNCO, ButNC and carbon disulfide is also described. A number of novel compounds were produced, including 169 from the reaction involving PhNCO. 
In contrast η2-(5-methoxy-2-acetylphenyl)tetracarbonylmanganese with ally1 isothiocyanate gave simply 2-allyl-4-methoxyacetophenone by allylation of the orthomanganated starting compound. Allyl bromide behaved similarly. However, allyl bromide and ethyl bromide when reacted with the cyclomanganated chalcone 54 gave furanone products (e.g. 190 and 191). An oxidative addition and reductive elimination mechanism was proposed to explain this reaction. 
Among others, the crystal structures of 50, 89 and 130 were determined.

text: Reactions of cyclomanganated compounds This thesis describes novel reactions of cyclomanganated compounds of the general form shown below. The ligand is bonded by a metal-carbon σ-bond, with X acting as a donor atom to form the chelate ring. The organic ligands were derived from aryl and heteroaryl ketones, chalcones, dienones and azabutadienes. 
A preliminary investigation has previously been undertaken into the reaction of carbon disulfide with some orthomanganated aryl ketones. In the present study these reactions were further investigated, with the isolation of new η2-S, S-dithiocarboxylate complexes, e.g. 46. In other cases the reaction of carbon disulfide with cyclomanganated compounds afforded the novel Mn4 species 50 in low yield. 
The reactions of orthomanganated acetyl-aryl compounds with organic isocyanides (C≡NR) afforded a number of novel compounds. For example η2-(2-acetylphenyl)-tetracarbonylmanganese (79) afforded four different types of products depending on the isocyanide; tert-butyl isocyanide produced 82, ethyl isocyanide produced 95 and 96, and 4-methoxyphenyl isocyanide produced 98 and 99. 
With orthomanganated 2-acetylthiophene, CNBut gave the quinone species 88 and 89,which showed high anti fungal and antitumor activity. 
Cyclomanganated dienones (e.g. 127) were previously known to react with alkynes to give either (η5-pyranyl)Mn(CO)3 (e.g. 130) or (η5-oxocycloheptadienyl)Mn(C0)3 (e.g.129) products. The factors influencing which product is formed were more systematically investigated and a deuterium-labelling experiment was used to probe the1,2-phenyl shift that occurs for the (η5-oxocycloheptadienyl)Mn(C0)3 products . 
A preliminary investigation of the reactions of 4-phenyl-1-(4-tolyl)-l-azabuta-1, 3-diene(TAD) with PhCH2Mn(CO)5 and unsaturated substrates including phenyl acetylene, methyl acrylate, PhNCO, ButNC and carbon disulfide is also described. A number of novel compounds were produced, including 169 from the reaction involving PhNCO. 
In contrast η2-(5-methoxy-2-acetylphenyl)tetracarbonylmanganese with ally1 isothiocyanate gave simply 2-allyl-4-methoxyacetophenone by allylation of the orthomanganated starting compound. Allyl bromide behaved similarly. However, allyl bromide and ethyl bromide when reacted with the cyclomanganated chalcone 54 gave furanone products (e.g. 190 and 191). An oxidative addition and reductive elimination mechanism was proposed to explain this reaction. 
Among others, the crystal structures of 50, 89 and 130 were determined.

year: 2003

title: Pressure cookers or pressure valves: Do roads lead to deforestation in China?

authors: Deng, Xiangzheng

subjects: deforestation

abstract: The effect of roads on forests is ambiguous. Many studies conclude that building and upgrading roads increases pressure on forests but some find that new and better roads may reduce the rate of deforestation. In this paper we use satellite remote sensing images of forest cover in Jiangxi Province, China, to test whether the existence and the size of roads (ranging from expressways to tertiary roads) in 1995 affected the level of forest cover in 2000 or the rate of change between 1995 and 2000. To account for road access for each of our 1 km2 (“pixel”) units of forest cover we measure whether or not and what type of roads penetrate the “watershed” in which the pixel lies. These watersheds allow more plausible measures of accessibility than do traditional “crowfly” distance measures that ignore topography. To account for possible confounding we also use 12 additional covariates: geographic and climatic variables (e.g., elevation, slope, rainfall, temperature, soil properties); demographic and economic variables (e.g., local population and GDP per square kilometer); and distance variables (e.g., distance to the nearest provincial capital). Although simple univariate OLS regressions show that forest levels are lower and deforestation rates higher either when there is a road, or when there is a higher quality road, these results are not robust. Controlling for all of the covariates and also using recently developed covariate matching techniques to estimate treatment effects, we find that roads in China’s Jiangxi Province can most safely be described as having no impact on the level of forests and no impact on the rate of deforestation.

text: Pressure cookers or pressure valves: Do roads lead to deforestation in China? The effect of roads on forests is ambiguous. Many studies conclude that building and upgrading roads increases pressure on forests but some find that new and better roads may reduce the rate of deforestation. In this paper we use satellite remote sensing images of forest cover in Jiangxi Province, China, to test whether the existence and the size of roads (ranging from expressways to tertiary roads) in 1995 affected the level of forest cover in 2000 or the rate of change between 1995 and 2000. To account for road access for each of our 1 km2 (“pixel”) units of forest cover we measure whether or not and what type of roads penetrate the “watershed” in which the pixel lies. These watersheds allow more plausible measures of accessibility than do traditional “crowfly” distance measures that ignore topography. To account for possible confounding we also use 12 additional covariates: geographic and climatic variables (e.g., elevation, slope, rainfall, temperature, soil properties); demographic and economic variables (e.g., local population and GDP per square kilometer); and distance variables (e.g., distance to the nearest provincial capital). Although simple univariate OLS regressions show that forest levels are lower and deforestation rates higher either when there is a road, or when there is a higher quality road, these results are not robust. Controlling for all of the covariates and also using recently developed covariate matching techniques to estimate treatment effects, we find that roads in China’s Jiangxi Province can most safely be described as having no impact on the level of forests and no impact on the rate of deforestation.

year: 2010

title: Māori wards in Tauranga Moana and Aotearoa: Liminal local government democracy

authors: Des Forges, Sandra

subjects: Māori wards

abstract: This thesis focuses on Māori representation within the highly contested arena of local government democracy in Aotearoa New Zealand. Limitations of the current Eurocentric model of local government democracy are considered at various spatial scales. Legislative changes to enable councils to establish Māori wards were launched in the early 2000s. Māori wards are defined locations where those on the Māori electoral roll vote for Māori ward candidates, resulting in dedicated Māori representation at elected member level. Until 2021 when the legislation was amended to remove the ability for public referenda to challenge council decisions on establishing Māori wards, however, little change occurred. Since then, 35 councils have established Māori wards for the 2022 local body elections.
The research asks how, and in what ways, do Māori wards decolonise local government and encourage greater Māori representation? To explore this question, the empirical chapters are framed around three key aspects of liminality; the in-between positioning of Māori wards reflecting a time of change; this liminal space being a time where unease and discomfort is experienced by some as Indigenous disparity is addressed; and the threshold positioning of Māori wards as a place of opportunity and creativity, where new ideas and practices may be considered. Geographical concepts of (un)belonging, exclusion and deep colonising reveal challenges for Māori participation at the level of local government decision-making. 
The research uses an Indigenous methodological framework, Te Ara Tika, based on a framework of Kaupapa Māori, and developed specifically for non-Māori researchers. Māori wards have been widely debated in the media, particularly at the time of changes to the Māori ward legislation in 2021. Thematic analysis of 122 media representations of the Māori ward debate constitutes part of the empirical evidence. Fourteen individual interviews with local government representatives, including elected Council members from Tauranga Moana and members of Te Rangapū Mana Whenua o Tauranga Moana Partnership, were conducted. Additionally, participant observations took place at three public meetings on Māori wards.
The way the current form of local government representative democracy impacts Māori representation is identified. The research demonstrates how local government continues to act as a tool of colonialism by privileging Western worldviews, institutions, and systems. The research finds that Māori wards are liminal democratic options that are both decolonising and deep colonising. Evidence shows that the liminal space of Māori wards is an opportunity to consider options for a way forward to reimagine local government as a place of belonging underpinned by Te Tiriti o Waitangi and Te Ao Māori principles. 
The research builds on decolonisation literatures that seek to unsettle the hegemony of Eurocentric institutions and systems within colonised countries such as Aotearoa. Providing a critical spatial perspective on the intersection of democracy, colonisation and Indigeneity, this thesis advances decolonising geographical knowledges. In particular, this research advances debates about democratic processes, exposing ways in which colonially-based local authority democratic mechanisms contribute to under-representation issues. A reimagined local government allows current hegemonic approaches to be rethought and provides insights for a shift towards genuine decolonising processes.

text: Māori wards in Tauranga Moana and Aotearoa: Liminal local government democracy This thesis focuses on Māori representation within the highly contested arena of local government democracy in Aotearoa New Zealand. Limitations of the current Eurocentric model of local government democracy are considered at various spatial scales. Legislative changes to enable councils to establish Māori wards were launched in the early 2000s. Māori wards are defined locations where those on the Māori electoral roll vote for Māori ward candidates, resulting in dedicated Māori representation at elected member level. Until 2021 when the legislation was amended to remove the ability for public referenda to challenge council decisions on establishing Māori wards, however, little change occurred. Since then, 35 councils have established Māori wards for the 2022 local body elections.
The research asks how, and in what ways, do Māori wards decolonise local government and encourage greater Māori representation? To explore this question, the empirical chapters are framed around three key aspects of liminality; the in-between positioning of Māori wards reflecting a time of change; this liminal space being a time where unease and discomfort is experienced by some as Indigenous disparity is addressed; and the threshold positioning of Māori wards as a place of opportunity and creativity, where new ideas and practices may be considered. Geographical concepts of (un)belonging, exclusion and deep colonising reveal challenges for Māori participation at the level of local government decision-making. 
The research uses an Indigenous methodological framework, Te Ara Tika, based on a framework of Kaupapa Māori, and developed specifically for non-Māori researchers. Māori wards have been widely debated in the media, particularly at the time of changes to the Māori ward legislation in 2021. Thematic analysis of 122 media representations of the Māori ward debate constitutes part of the empirical evidence. Fourteen individual interviews with local government representatives, including elected Council members from Tauranga Moana and members of Te Rangapū Mana Whenua o Tauranga Moana Partnership, were conducted. Additionally, participant observations took place at three public meetings on Māori wards.
The way the current form of local government representative democracy impacts Māori representation is identified. The research demonstrates how local government continues to act as a tool of colonialism by privileging Western worldviews, institutions, and systems. The research finds that Māori wards are liminal democratic options that are both decolonising and deep colonising. Evidence shows that the liminal space of Māori wards is an opportunity to consider options for a way forward to reimagine local government as a place of belonging underpinned by Te Tiriti o Waitangi and Te Ao Māori principles. 
The research builds on decolonisation literatures that seek to unsettle the hegemony of Eurocentric institutions and systems within colonised countries such as Aotearoa. Providing a critical spatial perspective on the intersection of democracy, colonisation and Indigeneity, this thesis advances decolonising geographical knowledges. In particular, this research advances debates about democratic processes, exposing ways in which colonially-based local authority democratic mechanisms contribute to under-representation issues. A reimagined local government allows current hegemonic approaches to be rethought and provides insights for a shift towards genuine decolonising processes.

year: 2023