title: β-Cyclomanganated 1,5-diphenylpenta-1,4-dien-3-ones and their reactions with alkynes: routes to η5-pyranyl--- and η5-oxocycloheptadienyl---Mn(CO)3 complexes

authors: Tully, Warren

subjects: Manganese

abstract: 1,5-Diphenylpenta-1,4-dien-3-ones (4) are cyclometalated with benzylpentacarbonylmanganese to form [[1-phenyl-2-((E)-3-phenylprop-2-en-1-oyl-κO)]ethenyl-κC1]tetracarbonylmanganese derivatives (5). Coupling of 5 with alkynes in some cases gives [4-phenyl-2-(2-phenylethenyl)pyranyl-η5]tricarbonylmanganese complexes (6) analogous to those previously reported for β-manganated chalcones, but in other cases an alternative cyclisation pathway subsequent to insertion of alkyne into the C---Mn bond leads to [6-oxo-4,7-diphenylcyclohepta-1,4-dienyl-1,2,3,4,5-η]tricarbonylmanganese complexes (7). The X-ray crystal structure determination is reported for one such compound, [6-oxo-2,4,7-triphenylcyclohepta-1,4-dienyl-1,2,3,4,5-η]tricarbonylmanganese (7a), derived from 1,5-diphenylpenta-1,4-dien-3-one and phenylacetylene. The 7-phenyl group is found to occupy the endo position, and a mechanism involving Mn-mediated aryl migration is suggested to explain this stereochemistry. The reaction of 7a with ammonium cerium(IV) nitrate gives a low yield of 2-nitro-3,5,7-triphenylcyclohepta-2,4,6-trien-1-one (9), whose structure was established by X-ray crystal structure analysis. The pyranyl complexes (6) provide the corresponding pyrylium triiodide salts (8) when demetalated with iodine.

text: β-Cyclomanganated 1,5-diphenylpenta-1,4-dien-3-ones and their reactions with alkynes: routes to η5-pyranyl--- and η5-oxocycloheptadienyl---Mn(CO)3 complexes 1,5-Diphenylpenta-1,4-dien-3-ones (4) are cyclometalated with benzylpentacarbonylmanganese to form [[1-phenyl-2-((E)-3-phenylprop-2-en-1-oyl-κO)]ethenyl-κC1]tetracarbonylmanganese derivatives (5). Coupling of 5 with alkynes in some cases gives [4-phenyl-2-(2-phenylethenyl)pyranyl-η5]tricarbonylmanganese complexes (6) analogous to those previously reported for β-manganated chalcones, but in other cases an alternative cyclisation pathway subsequent to insertion of alkyne into the C---Mn bond leads to [6-oxo-4,7-diphenylcyclohepta-1,4-dienyl-1,2,3,4,5-η]tricarbonylmanganese complexes (7). The X-ray crystal structure determination is reported for one such compound, [6-oxo-2,4,7-triphenylcyclohepta-1,4-dienyl-1,2,3,4,5-η]tricarbonylmanganese (7a), derived from 1,5-diphenylpenta-1,4-dien-3-one and phenylacetylene. The 7-phenyl group is found to occupy the endo position, and a mechanism involving Mn-mediated aryl migration is suggested to explain this stereochemistry. The reaction of 7a with ammonium cerium(IV) nitrate gives a low yield of 2-nitro-3,5,7-triphenylcyclohepta-2,4,6-trien-1-one (9), whose structure was established by X-ray crystal structure analysis. The pyranyl complexes (6) provide the corresponding pyrylium triiodide salts (8) when demetalated with iodine.

year: 2001-08-01

title: Boat electrofishing survey of common smelt and common bully in the Ohau Channel in December 2009

authors: Brijs, Jeroen

subjects: New Zealand

abstract: We conducted a boat electrofishing survey of the Ohau Channel, which flows from Lake Rotorua to Lake Rotoiti, on 7 December 2009. The purpose of this was to repeat surveys that took place on 13 December 2007 and 11 December 2008 concerning the longitudinal pattern in densities of common smelt (Retropinna retropinna) and common bully (Gobiomorphus cotidianus). Due to run timing and possibly low water clarity and high water flows, catch rates were lower than those found in 2007 and 2008 as we only caught 353 fish comprising three native species and two introduced species in 2.72 km of fished distance at a total of 10 sites. Native species caught were common smelt, common bully and longfin eel (Anguilla dieffenbachii) and introduced species were rainbow trout (Oncorhynchus mykiss) and goldfish (Carassius auratus). The total are fished was 10,884 m² (1.088 ha) giving an estimated density of 3.2 fish 100 m⁻².

text: Boat electrofishing survey of common smelt and common bully in the Ohau Channel in December 2009 We conducted a boat electrofishing survey of the Ohau Channel, which flows from Lake Rotorua to Lake Rotoiti, on 7 December 2009. The purpose of this was to repeat surveys that took place on 13 December 2007 and 11 December 2008 concerning the longitudinal pattern in densities of common smelt (Retropinna retropinna) and common bully (Gobiomorphus cotidianus). Due to run timing and possibly low water clarity and high water flows, catch rates were lower than those found in 2007 and 2008 as we only caught 353 fish comprising three native species and two introduced species in 2.72 km of fished distance at a total of 10 sites. Native species caught were common smelt, common bully and longfin eel (Anguilla dieffenbachii) and introduced species were rainbow trout (Oncorhynchus mykiss) and goldfish (Carassius auratus). The total are fished was 10,884 m² (1.088 ha) giving an estimated density of 3.2 fish 100 m⁻².

year: 2010

title: The art of dialogue with indigenous communities in the new biotechnology world

authors: Hudson, Maui

subjects: biotechnology

abstract: Te Hau Mihi Ata is a research project that aims to negotiate spaces for and develop processes of dialogue that allow for a deeper level of interaction between mtauranga Māori (Māori indigenous knowledge) and science. Over a two-year period a series of facilitated exchanges or wnanga were held focusing on areas of new technology (assisted reproductive technologies, life technologies, and future food technologies) that involved Māori scientists and people with expertise in mtauranga Māori. These dialogue events were designed to explore, through the challenge of considering new biotechnologies, the similarities and differences that emerge from approaching these issues from different knowledge paradigms. This paper will outline the key project findings from this series of exchanges including the barriers and facilitators to the dialogue process and knowledge exchange as well as discuss how participants created connections between scientific discourse and indigenous knowledge frameworks.

text: The art of dialogue with indigenous communities in the new biotechnology world Te Hau Mihi Ata is a research project that aims to negotiate spaces for and develop processes of dialogue that allow for a deeper level of interaction between mtauranga Māori (Māori indigenous knowledge) and science. Over a two-year period a series of facilitated exchanges or wnanga were held focusing on areas of new technology (assisted reproductive technologies, life technologies, and future food technologies) that involved Māori scientists and people with expertise in mtauranga Māori. These dialogue events were designed to explore, through the challenge of considering new biotechnologies, the similarities and differences that emerge from approaching these issues from different knowledge paradigms. This paper will outline the key project findings from this series of exchanges including the barriers and facilitators to the dialogue process and knowledge exchange as well as discuss how participants created connections between scientific discourse and indigenous knowledge frameworks.

year: 2012