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In this article I focus on an initiative to determine how a group of 7 purposefully recruited Grade 10 in-service life orientation teachers in the Dr Kenneth Kaunda district of the North West province conceptualise socio-environmental issues and aim to determine whether their teaching-learning practices are aligned with the expectations of the Curriculum and Assessment Policy Statement. A qualitative research design was used to generate data through semi-structured interviews. The data were analysed thematically. A critical finding was that a need exists to include a situated knowledge approach to real-life socio-environmental issues for the purpose of humanising life orientation for learners. With this article, I wish to contribute to a particular discourse with regard to real-life socio-environmental issues through humanising life orientation pedagogies through environmental education. The potential merits of such a transformative approach, which is grounded in a critical pedagogical paradigm, are discussed as well.

There is a lack of knowledge about how embodied educational practices can be used to challenge and problematise traditional Life Orientation teaching approaches that normally result in a lack of learner engagement on socio- environmental challenges. The objective of this small-scale exploratory qualitative study was therefore to establish whether Grade 10 Life Orientation teachers encouraged embodied learning experiences that are grounded in learners' lived experiences, creativity, expressive potential and perspectives. Data were generated from lesson observations combined with semi-structured individual interviews that were analysed thematically. The findings revealed that the participating teachers struggled to transform complex social and environmental matters into concrete embodied educational experiences for their learners. An additional finding highlighted the importance of how the Life Orientation curricula can serve as a stimulus to aid an embodied teaching-learning approach towards social and environmental responsibility. These findings provide a starting point for the development of a framework to guide Life Orientation teachers to employ embodied learning practices and, thus, meet the outcomes of the subject as envisaged in policy statements.

The primary aim of this qualitative case study was to explore the relevance of seven in-service Grade 10 Life Orientation teachers' teaching-learning operations in two different quintile schools regarding the curriculum topic social and environmental responsibility. Accounts of teaching-learning strategies were used to define the orientation of these seven participants towards the topic social and environmental responsibility, which primarily focuses on content relevant to the adolescent learner. The qualitative findings are discussed thematically and their implications for an adolescent-orientated Life Orientation curriculum are highlighted. Focusing on the teaching-learning strategies of a selected sample of Life Orientation teachers strengthen the merit for suggesting a multi-faceted framework to enhance curriculum outcomes and teaching quality regarding life skills education.

Life Orientation (LO) is judged by the Department of Basic Education to be critical for the development of social and environmental responsible behaviour among South African schoolchildren. Despite this crucial role, the research revealed that the participants in the study reported on do not succeed as expected with the fostering of competencies regarding social and environmental responsible knowledge, values and skills, as required by the South African Curriculum and Policy Assessment Statement. The research findings as obtained through structured classroom observations and semi-structured interviews and reported here, inspired the researchers to develop a generic and holistic framework which can assist LO teachers with the facilitation of social and environmental responsible knowledge, values and skills in a more positive and learner-centred way through environmental education.

The synthesis, electrochemistry and oxidative addition kinetics are presented for a new [Rh(β-diketonato)(CO)(PPh3)] complex (2), of rhodium metal complexed with a β-diketonato ligand, β-L1 = (CH3COC(C10H21OC6H4COO)COCH3)−, containing a long and sterically large chain (Rα = C10H21OC6H4COO) substituted at the α position. This rhodium triphenylphosphine complex (2), [Rh(β-L1)(CO)(PPh3)], was subsequently converted from a rhodium(i) to a rhodium(iii) complex, by chemical and electrochemical oxidation. The kinetics of the chemical conversion from RhI to RhIII, which was obtained by the oxidative addition reaction [Rh(β-L1)(CO)(PPh3)] + CH3I, demonstrated that the reaction occurs in two reaction steps, with a RhIII-alkyl species as the main reaction product. The sterically large and long chain (Rα = C10H21OC6H4COO) at the α-position of the β-diketonato ligand, did not at all affect either the second order reaction rate constant (k1) of the first oxidative addition step of the [Rh(β-L1)(CO)PPh3] + CH3I reaction, nor the value of the oxidation potential (Epa) of the electrochemical oxidation of [RhI(β-L1)(CO)PPh3] to a RhIII-species. This was proven via a literature study, by comparing the k1 and Epa values from this study with the respective rate constants (k1) and oxidation potentials (Epa) of a wide variety of related [Rh(β-diketonato)(CO)(PPh3)] complexes without such a Rα substituent at the α position. [ABSTRACT FROM AUTHOR]

A range of ferrocenyl aryl ethers of type Fc-O-Ar (Fc = Fe(η5-C5H5)(η5-C5HnX4-n); n = 2-4; X = H, P(O)(OEt)2, SO2CF3; Ar = 2,4-(NO2)2-C6H3, 4-NO2-C6H4) have been successfully prepared by using the nucleophilic aromatic substitution reaction (SNAr) of Fc-OLi (1a-Li) and electron-deficient aryl fluorides, enabling a new pathway to this rarely described family of organometallic compounds. Initial studies of 1a-Li and o-phosphonato-substituted hydroxyferrocenes (1b-Li) have also been performed, indicating a low nucleophilicity of the oxygen atom. The SNAr reaction protocol tolerates ortho substituents, e.g. phosphonato and sulfonyl groups, resulting in 1,2-X,O (X = S, P) ferrocenyl ethers that can be obtained in a one-pot synthesis procedure including 1,3-O → C anionic phospho- and thia-Fries rearrangements. Within these studies, the first 1,3-diortho-functionalized ferrocenyl aryl ether could be synthesized. An electrochemical study of the redox potentials of the obtained compounds allows conclusions on the reactivity of the varying electronic properties and the electrophilicity of different aryl fluorides and the nucleophilicity of the functionalized hydroxyl ferrocenes, which is directly reflected by the potential of the first ferrocene related redox processes. Chiral-pool-based phosphonates rearrange to the aryl ethers with diastereomeric excesses of 74 and 81% after the anionic Fries rearrangement. The usage of aryl 1,2-/1,3-difluorides resulted in the synthesis of the first examples of bis(FcO)-substituted benzenes. Their electrochemical investigations reveal a splitting of the two redox processes of the ferrocenyls that decreases from 155 mV (1,2-substitution) to 130 mV (1,3-substitution) on the basis of electrostatic interactions. [ABSTRACT FROM AUTHOR]

A series of Group 7 Fischer carbene complexes, [Cp(CO)2MnI=C(OEt)Ar] (Cp=cyclopentadienyl, Ar=Th=thienyl ( 1 a), Ar=Fu=furyl ( 2 a), Ar=Fc=ferrocenyl ( 3 a)) and biscarbene complexes, [Cp(CO)2MnC(OEt)Ar′(OEt)CMn(CO)2Cp] (Ar′=Th′=2,5-thienylene ( 1 b), Ar′=Fu′=2,5-furylene ( 2 b), Ar′=Fc′=1,1′-ferrocendiyl ( 3 b)) was synthesized and characterized. Chemical oxidation of [Cp(CO)2MnC(OEt)Fc] ( 3 a) and isolation of the oxidised species [3 a][PF6] possessing a MnII centre proved possible below −30 °C in dichloromethane solution. The ESR spectrum of the transiently stable radical cation, [3 a][PF6], confirmed the presence of a low-spin MnII centre characterized by a rhombic g tensor ( gx=1.975, gy=2.007 and gz=2.130) in frozen dichloromethane at 77 K with 55 Mn hyperfine coupling constants A1, A2 and A3 of 115, 33 and 43 G, respectively. Electrochemical studies demonstrated the influence of the Ar substituent on the oxidation potential. All complexes showed that the redox potentials of carbene double bond reduction and MnI oxidation were dependent on the type of Ar group, but only 3 b showed resolved oxidations for the two MnI centres. Surprisingly, MnI oxidation occurs at lower potentials than ferrocenyl oxidation. Density functional theory (DFT) calculations were carried out to delineate the nature of the species involved in the oxidation and reduction processes and clearly confirm that oxidation of MnI is favoured over that of ferrocene. [ABSTRACT FROM AUTHOR]

A series of ten ferrocenyl, furyl, and thienyl mono- and biscarbene chromium(0) complexes were synthesized and characterized spectroscopically and electrochemically. The single crystal structure of the biscarbene complex [(CO)5Cr-C(OEt)-Fu′-(OEt)C-Cr(CO)5] (4a) was determined: C20H12Cr2O13; triclinic; P1; a = 6.2838(5), b = 12.6526(9), c = 29.1888(19) Å, α = 89.575(2), β = 88.030(2), γ = 87.423(2)°; Z = 4. Results from an electrochemical study in CH2Cl2 were mutually consistent with a computational study in showing that the carbene double bond of 1 - 6 is reduced to an anion radical, -Cr-C• at formal reduction potentials < -1.7 V vs FcH/FcH+. The Cr centers are oxidized in two successive one electron transfer steps to Cr(II) via the Cr(I) intermediate. Only Cr(I) oxidation is electrochemically irreversible. Dicationic Cr(II) species formed upon two consecutive one-electron oxidation processes are characterized by a peculiar bonding situation as they are stabilized by genuine CH…Cr agostic interactions. With respect to aryl substituents, carbene redox processes occurred at the lowest potentials for ferrocene derivatives followed by furan complexes. Redox process in the thiophene derivatives occurred at the highest potentials. This result is mutually consistent with a 13C NMR study that showed the Cr-C functionality of furyl complexes were more shielded than thienyl complexes. The NHBu carbene substituent resulted in carbene complexes showing redox processes at substantially lower redox potentials than carbenes having OEt substituents. [ABSTRACT FROM AUTHOR]

A series of novel ferrocenylsubphthalocyanine dyads Y-BSubPc(H)12 with ferrocenyl-carboxylic acids Y-H = (FcCH2CO2-H), (Fc(CH2)3CO2-H) or (FcCO(CH2)2CO2-H) in the axial position were synthesized from the parent Cl-BSubPc(H)12 via an activated triflate-SubPc intermediate. UV/Vis data revealed that the axial ferrocenyl-containing ligand did not influence the Q-band maxima compared to Cl-BSubPc(H)12. A combined electrochemical and density functional theory (DFT) study showed that Fe group of the ferrocenyl-containing axial ligand is involved in the first reversible oxidation process, followed by a second oxidation localized on the macrocycle of the subphthalocyanine. Both observed reductions were ring-based. It was found that the novel Fc(CH2)3CO2BSubPc(H)12 exhibited the lowest first macrocycle-based reduction potential (−1.871 V vs. Fc/Fc+) reported for SubPcs till date. The oxidation and reduction values of Fc(CH2)nCO2BSubPc(H)12 (n = 0–3), FcCO(CH2)2CO2BSubPc(H)12, and Cl-BSubPc(H)12 illustrated the electronic influence of the carboxyl group, the different alkyl chains and the ferrocenyl group in the axial ligand on the ring-based oxidation and reduction values of the SubPcs. [ABSTRACT FROM AUTHOR]

Four new ferrocenylsubphthalocyanines Y-BSubPc, with ferrocenylcarboxylic acid YH = Fc-CH 2 -CH 2 -COOH ( 1 ) or Fc-CH═CH-COOH ( 2 ) in the axial Y position, were synthesized with a 40% yield. The axial ferrocenylcarboxylic acid moiety did not have a significant influence on the position of the Q bands maxima of the UV/vis spectra of the ferrocenylsubphthalocyanines or on the 1 H NMR position of the ring proton peaks of Y-BSubPc(H 12 ) or on the 19 F NMR position of the ring F peaks of YSubPc(F 12 ), relative to their respective parent compounds Cl-BSubPc(H 12 ) 3 and Cl-BSubPc(F 12 ) 4 , containing axial chlorine. Very weak metal-to-ligand-charge-transfer bands (MLCT) in the near-IR region were observed. An electrochemical study utilizing cyclic voltammetry showed that electronic communication exists between ferrocene on the axial ferrocenylcarboxylic acid and the π-electrons of the macrocycle of the ferrocenylsubphthalocyanine (Fc(CH 2 ) 2 COO)-BSubPc(H) 12 , 5 , (Fc(CH) 2 COO)-BSubPc(H) 12 , 6 , (Fc(CH 2 ) 2 COO)-BSubPc(F) 12 , 7 , and (Fc(CH) 2 COO)-BSubPc(F) 12 , 8 . The Fe group of the ferrocenyl-containing axial ligand is involved in the first reversible oxidation process, followed by a second oxidation localized on the subphthalocyanine ligand. The fluorine ring substituents in SubPcs 7 and 8 caused the ferrocenyl oxidation to shift more positive by ca . 0.1 V, compared to SubPcs 5 and 6 without fluorine. Density functional theory (DFT) calculations provided further insight into the properties of these novel ferrocenylsubphthalocyanines. The neutral species of SubPcs 5 - 8 have LUMOs with mainly π-ring character and HOMOs with mainly iron-d character, confirming ring-based reduction, metal-based Fe(II) to Fe(III) oxidation, as well as weak MLCT in the near-IR region. Further DFT optimization of the cation (oxidized) species was essential to verify the second ring-based oxidation.

A series of ferrocenyl and thienyl mono- and biscarbene chromium(0) complexes 1-6 were synthesised. The complexes were characterised both spectroscopically and electrochemically, and the single crystal X-ray structure of 3 was determined. Electrochemical measurements in CH2Cl2 revealed that the carbene double bond of 1-6 is reduced to an anion radical, (-)Cr-C˙ at formal reduction potentials <-1.7 V vs. FcH/FcH(+). A computational study on 1, 3 and 4 (B3LYP/def2-SVP level) is consistent with electrochemical results in showing that electrochemically generated chromium(I) species may be further electrochemically irreversibly oxidised to chromium(II) at Epa > 0.95 V. The reactivity towards follow-up chemical reactions of the anodically produced Cr(II) species is much higher than the reactivity of the cathodically produced radical anions as the latter was still observably reoxidised to the parent Cr=C species at fast scan rates. The ferrocenyl group is oxidised electrochemically reversibly to ferrocenium at larger potentials than the electrochemically reversible oxidation of the Cr(0) centre to Cr(I). That all redox centres in 1-6 are involved in one-electron transfer steps was confirmed by comparing the ferrocenyl voltammetric wave with those of the other redox centres in linear sweep voltammetric experiments. The ferrocenyl group was electrochemically shown to stabilise the Cr=C centre almost as much as the NHBu, and much more than the ethoxy and thienyl groups.