title: Synthesis and Characterisation of Cycloaurated Gold(III) Complexes with Bidentate (O,O), (N,S) and (S,S) Chelating Ligands

authors: Smith, Tiffany Sharee

subjects: Cycloaurated Gold(III) Complexes

abstract: The reaction of C,N-coordinated gold(III) dihalides; BpAuCl₂ (Bp = 2 benzylpyridyl), AnpAuCl₂ (Anp = 2 anilinopyridyl) and TypAuCl₂ (Typ = 2 tolylpyridyl) with catecholate ligands in hot methanol and trimethylamine produced metallacycles with structural isomers of the general formula (C,N)Au{O,O}. Similarly, BpAuCl₂ and AnpAuCl₂ were reacted with thiourea ligands to form complexes giving high yield and good purity with the general formula (C,N)Au{PhNCSNR₂}+, by means of the addition of BPh₄- for precipitation. X-ray crystal structures of the compounds [AnpAu{PhNCSNMe₂}]BPh₄ and [AnpAu{PhNCSNCy₂}]BPh₄ confirmed the coordination of the thiourea to the gold centre through the N and S atoms. In both cases the geometry around the gold atom is square-planar with complex [AnpAu{PhNCSNCy₂}]BPh₄ showing a slightly more puckered conformation than [AnpAu{PhNCSNMe₂}]BPh₄ due to the sterically bulky cyclohexyl groups attached. Some thiourea derivatives were tested against P388 murine leukaemia cells with complex [AnpAu{PhNCSNHPh}]BPh₄ showing promising anti-tumour activity.

When thiourea ligands were replaced by dithiophosphinate and dithiophosphate ligands the reaction proceeded at room temperature without the need for the presence of a base. Relatively low yields of impure metallacycles with the general formula (C,N)Au{S₂PR₂}+ were obtained on the addition of BPh₄- or BF₄-. Attempts to improve purity by varying batches of starting materials, anion and solvents used were unsuccessful. X-ray crystal data from a single crystal of [(C,N)Au{S₂PPh₂}]BPh₄ shows the reduction of gold(III) to gold(I) forming a known polymeric gold(I) dithiophosphinate complex. In order to extend this study the synthesis of complexes with the general formula R₂PS₂AuCl₂ was attempted, but no new compounds were characterised.

Where possible, all new compounds reported in this thesis were characterised by ES-MS, IR, NMR, melting point and micro-elemental analysis.

text: Synthesis and Characterisation of Cycloaurated Gold(III) Complexes with Bidentate (O,O), (N,S) and (S,S) Chelating Ligands The reaction of C,N-coordinated gold(III) dihalides; BpAuCl₂ (Bp = 2 benzylpyridyl), AnpAuCl₂ (Anp = 2 anilinopyridyl) and TypAuCl₂ (Typ = 2 tolylpyridyl) with catecholate ligands in hot methanol and trimethylamine produced metallacycles with structural isomers of the general formula (C,N)Au{O,O}. Similarly, BpAuCl₂ and AnpAuCl₂ were reacted with thiourea ligands to form complexes giving high yield and good purity with the general formula (C,N)Au{PhNCSNR₂}+, by means of the addition of BPh₄- for precipitation. X-ray crystal structures of the compounds [AnpAu{PhNCSNMe₂}]BPh₄ and [AnpAu{PhNCSNCy₂}]BPh₄ confirmed the coordination of the thiourea to the gold centre through the N and S atoms. In both cases the geometry around the gold atom is square-planar with complex [AnpAu{PhNCSNCy₂}]BPh₄ showing a slightly more puckered conformation than [AnpAu{PhNCSNMe₂}]BPh₄ due to the sterically bulky cyclohexyl groups attached. Some thiourea derivatives were tested against P388 murine leukaemia cells with complex [AnpAu{PhNCSNHPh}]BPh₄ showing promising anti-tumour activity.

When thiourea ligands were replaced by dithiophosphinate and dithiophosphate ligands the reaction proceeded at room temperature without the need for the presence of a base. Relatively low yields of impure metallacycles with the general formula (C,N)Au{S₂PR₂}+ were obtained on the addition of BPh₄- or BF₄-. Attempts to improve purity by varying batches of starting materials, anion and solvents used were unsuccessful. X-ray crystal data from a single crystal of [(C,N)Au{S₂PPh₂}]BPh₄ shows the reduction of gold(III) to gold(I) forming a known polymeric gold(I) dithiophosphinate complex. In order to extend this study the synthesis of complexes with the general formula R₂PS₂AuCl₂ was attempted, but no new compounds were characterised.

Where possible, all new compounds reported in this thesis were characterised by ES-MS, IR, NMR, melting point and micro-elemental analysis.

year: 2012

title: Editorial: Coping with stress: A challenge for theory, research and practice

authors: O’Driscoll, Michael P.

abstract: One of the major issues in research on human stress is how people deal with or manage the stressors which they confront in their daily lives, and how well they deal with these stressors. This is normally referred to as ‘coping’, which has been a topic of significant interest to stress researchers for many years. Various articles published in Stress and Health have examined coping behaviours, in respect of many types of stressful situation, including physical illness, interpersonal relations at home, work stressors and traumatic events such as earthquakes and floods. These papers have illustrated the range of coping strategies which humans engage in.

text: Editorial: Coping with stress: A challenge for theory, research and practice One of the major issues in research on human stress is how people deal with or manage the stressors which they confront in their daily lives, and how well they deal with these stressors. This is normally referred to as ‘coping’, which has been a topic of significant interest to stress researchers for many years. Various articles published in Stress and Health have examined coping behaviours, in respect of many types of stressful situation, including physical illness, interpersonal relations at home, work stressors and traumatic events such as earthquakes and floods. These papers have illustrated the range of coping strategies which humans engage in.

year: 2013

title: Teaching te reo Māori as a second language in primary schools: two case studies.

authors: Hill, Richard Kenneth

subjects: second languages

abstract: The provision of second language education in New Zealand primary schools has been, until recently, a rare addition to programmes. Its wider implementation in New Zealand primary schools has always been limited by low numbers of fluent bilingual teachers, and a perception that in a predominantly English speaking country such as New Zealand there is no need to teach additional languages in primary schools. The New Zealand Curriculum (Ministry of Education, 2007) provides the first opportunity to formally include second language education in primary schools, and to establish the learning of second languages as a worthwhile pursuit in New Zealand. However, the success of such a policy change will depend on the ability of the Ministry of Education and course providers to upskill teachers in their ability to speak additional languages and teach them. This article reports on the outcomes of a Ministry-funded project designed to strengthen the second language teaching approaches of upper primary school teachers who teach te reo Maori. It provides case studies of two of the teachers who completed this course, and finds that while there are clear benefits to be derived from such teacher professional development courses, these courses need to focus on long-term objectives and be channelled to those teachers and students who stand to benefit the most from professional development courses.

text: Teaching te reo Māori as a second language in primary schools: two case studies. The provision of second language education in New Zealand primary schools has been, until recently, a rare addition to programmes. Its wider implementation in New Zealand primary schools has always been limited by low numbers of fluent bilingual teachers, and a perception that in a predominantly English speaking country such as New Zealand there is no need to teach additional languages in primary schools. The New Zealand Curriculum (Ministry of Education, 2007) provides the first opportunity to formally include second language education in primary schools, and to establish the learning of second languages as a worthwhile pursuit in New Zealand. However, the success of such a policy change will depend on the ability of the Ministry of Education and course providers to upskill teachers in their ability to speak additional languages and teach them. This article reports on the outcomes of a Ministry-funded project designed to strengthen the second language teaching approaches of upper primary school teachers who teach te reo Maori. It provides case studies of two of the teachers who completed this course, and finds that while there are clear benefits to be derived from such teacher professional development courses, these courses need to focus on long-term objectives and be channelled to those teachers and students who stand to benefit the most from professional development courses.

year: 2010