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Palladium catalysed hydroesterification and aminocarbonylation of substituted alkenes and alkynes
No full textSince the aim of this study was to investigate the influence of the electronic environment
around the double bond of alkenes on the reactivity and regioselectivity of the
methoxycarbonylation reaction for developing new methodology towards the synthesis of
isoflavonoids, several aryl substituted alkenes were subjected to methoxycarbonylation
utilizing the Pd(OAc)2/Al(OTf)3/PPh3 catalyst system in MeOH under the optimum
conditions of 35 bar of CO pressure and 95 °C. In order to be able to compare current results
with literature values, 1-octene, 2-octene and styrene, were the first substrates to be
methoxycarbonylated and gave anticipated high conversions (100%, 83% and 91%,
respectively) to the expected linear (l) and branched (b) methyl esters, methyl nonanoate and
methyl 2-methylnonanoate as well as methyl 3-phenylpropanoate and methyl 2-
phenylpropanoate, respectively in a l:b ratio of ca. 3:1. A set of trans-β-methylstyrene
analogues, i.e. trans-β-methylstyrene, trans-p-methoxy-β-methylstyrene and trans-omethoxy-
β-methylstyrene as well as a set of allylbenzene analogues, i.e. allylbenzene, pmethoxyallylbenzene,
p-trifluoromethylallylbenzene, o-methoxyallylbenzene and otrifluoromethanesulfonyloxyallylbenzene
were subjected to the methoxycarbonylation
reaction conditions and the products obtained in high conversions (88-96%) except for the
alkenes with methoxy substituents in the para-position, i.e. p-methoxy-β-methylstyrene and
p-methoxyallylbenzene (49% and 66%, respectively). During these investigations
isomerization of the double bond in the β-methylstyrenes to the terminal position, forming
allylbenzene analogues proved to be a feasible side-reaction, so the same products, i.e. linear
(l), branched (b) and benzylic (bn) carboxylated products were formed from the β-
methylstyrenes and corresponding allylbenzenes. During the investigation it was also found
that a p-methoxy substituent on the β-methylstyrene or allylbenzene resulted in a decrease in
reaction rate, while an o-methoxy substituent increases the reaction rate substantially in
comparison to the p-methoxy analogues. Ortho-substituents (methoxy or triflate group) also
resulted in a drastic increase in the formation of the linear products for both the β-
methylstyrene and allylbenzene substrates, i.e. 3:2:1 vs. 10:4:1 and 8:2:1 vs. 15:5:1 vs. 5:1:0,
respectively. It was also determined that a more electron-rich aromatic ring has an enhancing
effect on the formation of the benzylic products as was determined by the methoxycarbonylation
of 1,3-diphenylpropene, which gave methyl 2,4-diphenylbutanoate in 64%
yield and 95% regioselectivity. Sterically more demanding disubstituted and trisubstituted
double bonds, like in α-methylstyrene and 2-methyl-1-phenylprop-1-ene, were also subjected
to the methoxycarbonylation reaction and resulted in the formation of methyl 3-
phenylbutanoate in 63% and methyl 3-methyl-4-phenylbutanonate in 26% yield, respectively,
albeit after extended reaction periods (4-6 h).
Since the availability of CO and thus the CO concentration in solution should have a
significant influence on the rate of the reactions unless CO is not involved in the rate limiting
step of the process, the effect of mass transfer limitations on the reaction rate of the substrates
mentioned above were also studied and it was found that an 8-18% increase in reaction rates
were observed for conditions of proper mass transfer for styrene, allylbenzene, and p- and omethoxyallylbenzenes
where isomerization of the double bond is insignificant.
Since hydroesterification under microwave radiation conditions has not been reported to date,
the effect, if any, of microwave radiation vs. thermal heating conditions were also
investigated. Owing to the pressure limit (12 bar) of the glass reaction vessel in the
microwave reactor all reactions were executed at 12 bar in order to allow direct comparison of
the results and a definite increase in reaction rate (99% conversion after only 10 min. vs. 99%
after 30 min. at 35 bar) was observed for the microwave hydroesterification reactions of 1-
octene and styrene. Although a general increase in reaction rate was not found for the
allylbenzene substrate, a ca. 15% increase in yield was observed for p-methoxyallylbenzene
(20% vs. 37%), o-methoxyallylbenzene (73% vs. 89%) and β-methylstyrene (66% vs. 88%)
as substrates when the microwave reactions were compared to those performed under
conventional heating under the same pressure.
When the nucleophile in the carbonylation reactions was changed from oxygen (methanol) to
nitrogen (aniline) and the ligand to BINAP in the same catalyst system, the first
aminocarbonylation reaction was observed. Reaction of the o- and p-methoxy substituted
allylbenzenes with aniline, anisidine and 4-chloroaniline resulted in the successful formation
of the linear and branched amides (anilides) in 87-97% yield. Extending the methodology to
trans-β-methylstyrene and α-methylstyrene with aniline, however, gave the amides in only
18% and 16% yield, respectively. When the aminocarbonylation of allylbenzene was
investigated with strongly deactivated anilines (2,4-dichloro- and 4-nitroaniline), primary
amines (butylamine and benzylamine) and amides (acetamide) no product formation could be
detected, so it was suspected that the reaction may be dependent on the pKa of the amine, with
pKa-values below 3 being too acidic and pKa-values above 9 basic enough to be deactivated
by complexation to the Lewis acid [Al(OTf)3] in the catalyst system. Although the successful
hydroamidation (25% conversion) of 4-chlorobenzylamine (pKa = 9.17) gave some credence
to this hypothesis, this aspect of the investigation still needs more attention in a follow-up
investigation.
Subsequently, attention was turned towards the original aim of this project, i.e.
methoxycarbonylation of stilbene analogues. Unsubstituted stilbene, 4-methoxystilbene and
2-methoxystilbene, however, gave poor results (conversions = 16-19% and yields = 2-6%),
although some selectivity (4:1 for 2-methoxystilbene) towards the formation of the distal
isomer, i.e. methyl 3-(2-methoxyphenyl)-2-phenylpropanoate, was observed.
Since the alkoxycarbonylation of alkynes is a well-documented reaction and these substrates
could also function as starting material for the synthesis of isoflavonoids, albeit with an
additional reduction step, the investigation was changed to the methoxycarbonylation of
substituted diphenylacetylenes. In order to evaluate the influence of electron-donating and
electron-withdrawing substituents on the rings of the phenylphenylacetylenes on the
regioselectivity of the reactions, 4-methoxyphenyl- and (2-methoxyphenyl)phenylacetylene
were prepared both in 69% yield by utilizing the Sonogashira coupling under conventional
heating conditions (CuI/DABCO/K2CO3/DMF). (2,4-Dimethoxyphenyl)phenylacetylene was
prepared in 91% yield by utilizing the Pd(PPh3)2Cl2/CuI/Et2NH/DMF reagent system under
microwave irradiation (200 W). The electron-deficient diphenylacetylenes, (4-
trifluoromethanesulfonyloxyphenyl)phenylacetylene, 4-methoxyphenyl-4'-trifluoromethanesulfonyloxyphenylacetylene
and 4-methoxyphenyl-2',4'-bis(trifluoromethanesulfonyloxy)-
phenylacetylene, were prepared in overall 81%, 87% and 19% yields via Sonogashira
coupling and formation of the triflate from the free phenolic analogues.
The 2-, 4-methoxy and 4-triflate substituted diphenylacetylenes, with the exception of (2,4-
dimethoxyphenyl)phenylacetylene, were excellent substrates for the methoxycarbonylation
reaction catalysed by Pd(OAc)2/Al(OTf)3/BINAP and gave good to excellent conversions
(>97%) and yields (89%, 89% and 71%). Owing to Lewis acid catalysed methanol addition
to the triple bond and subsequent demethylation, (2,4-dimethoxyphenyl)phenylacetylene gave
only 35% of the desired product, which was accompanied by 46% of the corresponding
deoxybenzoin. While some selectivity towards the proximal isomer of the esters were found
for the two monomethoxy substituted diphenylacetylenes (2:1, proximal:distal), the methoxy
carbonylation of (4-trifluoromethanesulfonyloxyphenyl)phenylacetylene gave the two esters
in a ratio of 1:1. Methoxycarbonylation of the 4-methoxyphenyl-4'-trifluoromethanesulfonyloxyphenylacetylene
and 4-methoxyphenyl-2',4'-bis(trifluoromethanesulfonyloxy)-
phenylacetylene led to the two ester products in 71 and 72% yields, respectively with the
proximal isomer (carboxylate function next to the methoxy carrying ring) obtained in a 3:1
and excellent 18:1 ratio, respectively.
It was thus amply demonstrated that substituted diphenylacetylenes can be methoxycarbonylated
successfully and that high selectivity towards the isomer that would allow
cyclization to the 6-membered heterocyclic ring of the isoflavonoid nucleus is possible.
Method development for the preparation of diphenylacetylenes with substitution patterns
resembling those found in naturally occurring isoflavonoids and the synthesis of those
isoflavonoids could therefore be embarked upon with confidence. Complete development of
this new methodology towards the synthesis of isoflavonoids and the preparation of these
compounds in enantiomerically pure form through stereoselective reduction of the remaining
double bond in the methoxycarbonylated diphenylacetylenes, will receive further attention in
a follow-up investigation.University of the Free Stat
Do social grants contribute to the jobless population growth in the former South African homelands?
No full textThe former homelands and tribal authorities have large populations and high densities with low levels of economic activity and low employment. Population growth in these settlements is in contrast to expectations of population declines, due to urban migration. A possible reason could be the high level of dependency on social grants in the former homelands. The article analyses population growth rates, economic growth rates and the ratio of social grant recipients within former homeland settlements between 1996 and 2011. By using weighted multiple regression tests, the article determines whether the phenomenon of population growth, in the absence of significant economic activity, is linked to welfare transfers. The results indicate that population growth is the product of increases in age cohorts qualifying for social grants in rural areas, due to high birth rates and pensioner in-migration from urban areas. By contrast, other age cohorts show population declines.Publisher's versio
The concept of "the holy seed" as a coping strategy in Ezra-Nehemiah and its implications for South Africa
No full textIn a study describing the problems experienced by former political exiles who have returned to South Africa since 1990, Majodina argues that the psychological study of reintegration of refugees/exiles deserves a place in mainstream psychological research and not remain on the fringes. One of her basic assumptions is that coping plays a key mediating role in the reintegration process. Taking cue from her deliberation, this article aims to investigate the role played by psychological coping in the return of Judean exiles from Babylon in Ezra-Nehemiah. It examines these coping strategies in light of Tajfel’s and Turner’s theories of the Social Identity Approach (SIA) to give intelligibility to the ideologies that transpire. The article also presents Majodina’s Social Coping strategy to provide background for the discussion of implications for South Africa. The discussion culminates in the examination of implications of this discussion for South Africa. Where necessary, some South African neighbouring countries may be referred to, in order to illuminate the discussion.Publisher's versio
VAN ROOYEN, G.J. Minute Books
No full textCOVERAGE: 1911-1952; 0.04 metresTwo meeting minutes books of the National Party branch Arundel, Senekal (1911-1948; 1949-1952
Implisiete etiek in die brief aan Filemon
No full textEnglish: This brief letter written to Philemon by the apostle Paul contains various issues about which there is much uncertainty among interpreters. As a result the ethics of Philemon is described in many different ways. When researchers describe the ethics of Philemon an obvious ethical issue arises from the letter, namely the issue of slavery. Discussions on the theology (and ethics) of Philemon, with one or two exceptions, focus on the slavery issue – researchers follow the same underlying pattern in their description of the theology and ethics of Paul’s Letter to Philemon, namely that they reduce the ethics of the letter to Paul’s handling of the slavery issue.
This study aims to investigate this tendency in the study of the ethics of the Philemon based upon the following hypothesis: If one follows another, more comprehensive approach to the ethics of Philemon – as apposed to one that only focuses on the slavery issue – a fuller/ better/ more comprehensive description of the ethics of the letter can be achieved.
This hypothesis was tested by specifically making use of the more comprehensive approach to New Testament ethics prescribed by Ruben Zimmermann, namely the model of “implicit ethics”. The aim was, by applying the different phases of the model to the text of Philemon, to demonstrate how the ethical reach of the letter stretches much further than the slavery issue.Afrikaans: Hierdie kort briefie wat Paulus aan Filemon skryf, bevat ʼn aantal aspekte waaroor uitleggers nog nie duidelikheid het nie. Só word die etiek van Filemon ook op uiteenlopende maniere beskryf. Wanneer navorsers die etiek van Filemon beskryf, is daar ’n voor die hand liggende etiese kwessie wat vanuit die brief na vore kom, nl. die slawerny-kwessie. Besprekings oor die teologie (en etiek) van Filemon, met een of twee uitsonderings, fokus op die kwessie van slawerny – navorsers volg dieselfde onderliggende patroon in hulle beskrywing van die teologie en etiek van Paulus se Brief aan Filemon, naamlik dat hulle die etiek van die brief reduseer tot Paulus se hantering van die slawerny-kwessie.
Hierdie studie wil hierdie verskynsel in die bestudering van die etiek van Filemon ondersoek met die volgende hipotese as vertrekpunt: Indien ’n ander, breër, benadering tot die etiek van Filemon gevolg word as een wat net op die slawerny-kwessie fokus, kan ’n meer omvangryke/beter/voller beskrywing van die etiek van die brief verkry word.
Hierdie navorsingshipotese is getoets deur spesifiek van die breër benadering tot Nuwe-Testamentiese etiek wat deur Ruben Zimmermann voorgestel word, gebruik te maak –nl. die “implisiete etiek”-model. Deur die verskillende invalshoeke van die model op die teks van Filemon toe te pas, is daar gepoog aan te dui hoe die etiese reikwydte van die brief veel wyer strek as die slawerny-kwessie
KESTELL, Truida [Trudie] Inventory of documents
No full textCOVERAGE 1859-1974; 30 Files; 055 metrePrivate papers of T. Kestell, author of Ons Volksdrag [1940] and Wat het hulle gedra [1951], Honorary Curator of the National Museum, Bloemfontein, youngest daughter of J.D. Kestell
VAN ZIJL, Christiaan de Wet Inventory of documents
No full textCOVERAGE 1910-1965; 1 File; 0,22 Metre.Private papers of C. de W. van Zijl, clerk Department of the Interior [1922-1963]
NATIONAL YOUTH LEAGUE OFS Inventory of documents
No full textCOVERAGE 1942-1973; 61 Files; *2,78 Metres.Papers of the National Youth League OFS, founded in 1943
Coordination chemistry of niobium(v) and tantalum(v) with hard o-donor ligands: a solution and solid state investigation
No full textEnglish: This thesis describes the study directed towards the synthesis, characterization and substitution kinetics of novel niobium(V) and tantalum(V) complexes containing selected O,O’-bidentate ligands that could potentially be used for the separation of niobium from tantalum. There is also a search for complexes that will be attractive and useful as advanced materials for high technology applications and in the nuclear power environment. The study included systematic assessment of the physical and chemical behaviour of the free ligands, co-crystals and complexes as well as the factors which govern their stability, reactivity, coordination geometry, bond lengths and angles, π-π stacking interaction and inter- and intramolecular networks of hydrogen bonds. It became evident that the crystal stabilization was influenced by intermolecular π-π interactions and inter- and intramolecular hydrogen and halogen bond networks, producing a stabilized crystal lattice. A range of Nb(V) and Ta(V) complexes such as cis-(Et4N)[NbO(ca)2(H2O)OPPh3]·3H2O-·THF (5), (Et4N)4[Nb4O4(ca)2(μ2-O)2C18]·2CH3CN (6), [NbO(cupf)3] (7), [NbO(hopo)3]. MeOH (8), [TaO(hopo)3]·MeOH (9), [Ta(hopo)4]C1·2MeCN·2H2O (10) (where ca = 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinonato, cupf = N-nitroso-N-phenylhydroxylaminato, hopo = 2-hydroxypyridinato-N-oxide) as well as two co-crystals [OPPh3½(caH2)] (2) and [(2½(caH2)(DMAP)6·11H2O)] (4) were prepared and characterised by IR (ATR), NMR (1H, 13C and 31P), UV-Vis spectroscopy and single crystal X-ray diffraction. Additionally, two free ligands, [½(caH2)·H2O] (1) and [hopoH] (3), were characterised by single crystal X-ray diffraction. The six-, seven- and eight coordinate geometries show different coordination modes as observed in complexes (5) and (7) (D5h pentagonal bipyramidal geometry), (6) (a regular octahedral coordination mode), (8) (C3v-capped octahedral geometry), (9) (C2-capped trigonal prismatic geometry) and (10) (D2-square antiprismatic geometry). Therefore, these different geometries found in complexes (5), (6), (7), (8), (9) and (10) describe the shape of complexes with six, seven and eight oxygen atoms bound to the niobium(V) and tantalum(V) metal centres, with the differences playing a possible key role to increase the potential of a new type of separation of niobium from tantalum. Starting with the selected complex, cis-[NbO(ca)2(H2O)(OPPh3)]-, the substitution of the triphenyl-phosphineoxide by pyridine-type ligands such as pyridine (py), 4-N,N-dimethyl-aminopyridine (DMAP), 4-methylpyridine (4-Mepy), 3-chloropyridine (3-Clpy) and 3-bromopyridine (3-Brpy) in acetonitrile media at 31.2°C were determined and evaluated. These entering monodentate ligands could be arranged in terms of their increasing reactivity values: 3-Brpy < 3-Clpy < 4-Mepy < py < DMAP, defined by the values of kf = 0.147(4) x 10-2; 0.206(7) x 10-2; 0.181(6) x 10-2; 0.131(2) x 10-2 and 2.032(2) x 10-2 M-1s-1 respectively. The pseudo first-order rate constants were dependent on concentration and temperature. From the observed kinetic results a suitable mechanism was proposed. Activation parameters were determined for the reaction of the complex, cis-[NbO(ca)2(H2O)(OPPh3)]-, with 4-N,N-dimethylaminopyridine (DMAP) as entering ligand. The activation parameters for these triphenylphosphineoxide substitution reactions were calculated as 51.5(9) k J mol-1 and -108(3) J K-1 mol-1 for the standard change of enthalpy (ΔH≠(kf)) and the standard change of entropy (ΔS≠(kf)) respectively. The negative entropy of activation implies a more ordered state and presumably this substitution reaction could involve an associative ligand substitution mechanism. Although only part of a preliminary study, a range of novel Nb(V) and Ta(V) complexes with O,O’-, O,N- and N,N’-bidentate ligands were synthesised and characterised by IR (ATR), NMR (1H and 13C) and UV-Vis spectroscopy. The reaction of [NbCl6]- with chloranilic acid (caH2) in solution gave cis-[NbO(ca)2(H2O)]-, which react further with added triphenylphosphineoxide (OPPh3) to give the final product, cis-[NbO(ca)2(H2O)OPPh3]-. Knowledge obtained from this study should contribute to the understanding of the chemical and physical properties of the various Nb(V) and Ta(V) complexes and identify possible differences to apply in future for developing potential separation methods for niobium from tantalum.Afrikaans: Hierdie tesis beskryf die studie wat gerig was op die sintese, karakterisering en substitusie-kinetika van nuwe niobium(V) en tantalum(V) komplekse wat geselekteerde O,O’-bidentate ligande bevat wat moontlik gebruik kan word vir die skeiding van niobium en tantalum. Daar is ook ‘n soektog na komplekse wat aanloklik en nuttig as gevorderde stowwe vir hoë tegnologie toepassings en in die kernkrag omgewing sal wees. Die studie het ‘n sistematiese beoordeling van die fisiese en chemiese gedrag van die vry ligande, ko-kristalle en komplekse asook die faktore wat hulle stabiliteit, reaktiwiteit, koördinasiegeometrie, bindingslengtes- en hoeke, π-π stapelingsinteraksie en inter- sowel as intramolekulêre netwerke van waterstofbindings ingesluit. Dit het duidelik geword dat die kristalstabilisasie beïnvloed is deur intermolekulêre π-π interaksies asook inter- en intramolekulêre netwerke van waterstof- en halogeenbindings, wat ‘n gestabiliseerde kristalrooster tot gevolg het.
‘n Reeks van Nb(V) en Ta(V) komplekse soos cis-(Et4N)[NbO(ca)2(H2O)OPPh3]·3H2O- ·THF (5), (Et4N)4[Nb4O4(ca)2(μ2-O)2Cl8]·2CH3CN (6), [NbO(cupf)3] (7), [NbO(hopo)3]- ·MeOH (8), [TaO(hopo)3]·MeOH (9), [Ta(hopo)4]Cl·2MeCN·2H2O (10) (waar ca = 2,5-dichloro-3,6-dihidroksi-1,4-bensokwinonato, cupf = N-nitroso-N-fenielhidroksielaminato, hopo = 2-hydroksipiridinato-N-oksied) sowel as twee ko-kristalle, [OPPh3½(caH2)] (2) en [(2½(caH2)(DMAP)6·11H2O)] (4) is berei en gekarakteriseer deur IR (ATR), KMR (1H, 13C en 31P), UV-Vis spektroskopie en enkelkristal X-straaldiffraksie. Bykomend is twee vry ligande, [½(caH2)·H2O] (1) en [hopoH] (3), gekarakteriseer deur enkelkristal X-straaldiffraksie.
Die ses-, sewe- en agtgekoordineerde geometrieë vertoon verskillende wyses van koördinering soos waargeneem in komplekse (5) en (7) (D5h pentagonale bipiramidale geometrie), (6) (‘n gewone oktahedriese koördinering), (8) (C3v-gekroonde oktahedriese geometrie), (9) (C2-gekroonde trigonale prismatiese geometrie) en (10) (D2-vierkantig antiprismatiese geometrie). Die verskillende geometrieë soos waargeneem in komplekse (5), (6), (7), (8), (9) en (10) beskryf die vorm van komplekse met ses, sewe en agt suurstofatome gebonde aan die niobium(V) en tantalum(V) metaalsentrums, waar die verskille ‘n moontlike sleutelrol kan speel om die potensiaal van ‘n nuwe tipe skeiding van niobium van tantalum te vergroot.
Beginnende met die gekose kompleks, cis-[NbO(ca)2(H2O)(OPPh3)]-, is die substitusie van trifenielfosfienoksied deur piridien tipe ligande soos piridien (py), 4-N,N-dimetiel-aminopiridien (DMAP), 4-metielpiridien (4-Mepy), 3-chloropiridien (3-Clpy) en 3-bromopiridien (3-Brpy) in asetonitrielmedium by 31.2 oC bepaal en ge-evalueer. Hierdie inkomende monodentate ligande kan gerangskik word in terme van hulle toenemende reaktiwiteitswaardes: 3-Brpy < 3-Clpy < 4-Mepy < py < DMAP, gedefinieer deur die waardes van kf = 0.147(4) x 10-2; 0.206(7) x 10-2; 0.181(6) x 10-2; 0.131(2) x 10-2 en 2.032(2) x 10-2 M-1s-1 respektiewelik. Die pseudo eerste-orde tempokonstantes was afhanklik van konsentrasie en temperatuur. Vanaf die waargenome kinetiese resultate kon ‘n toepaslike meganisme voorgestel word.
Aktiveringsparameters is bepaal vir die reaksie van die kompleks, cis-[NbO(ca)2(H2O)(OPPh3)]- met 4-N,N-dimetielaminopiridien (DMAP) as inkomende ligand. Die aktiveringsparameters vir hierdie trifenielfosfienoksied substitusiereaksies is bereken as 51.5(9) k J mol-1 en -108(3) J K-1 mol-1 vir die standaard entalpieverandering (ΔH≠(kf)) en die standaard entropieverandering (ΔS≠(kf)) respektiewelik. Die negatiewe aktiveringsentropie impliseer ‘n meer geordende toestand en dat hierdie substitusiereaksie moontlik volgens ‘n assosiatiewe meganisme van ligandsubstitusie plaasvind.
Alhoewel slegs deel van ‘n voorlopige studie, is ‘n reeks nuwe Nb(V) en Ta(V) komplekse met O,O’-, O,N- en N,N’-bidentate ligande berei en gekarakteriseer met behulp van IR (ATR), KMR (1H and 13C) en UV-Vis spektroskopie. Die reaksie van [NbCl6]- met chlooranilieksuur (caH2) in oplossing lewer cis-[NbO(ca)2(H2O)]-, wat verder met bygevoegde trifenielfosfienoksied (OPPh3) reageer om die finale produk cis-[NbO(ca)2(H2O)OPPh3]- te lewer.
Kennis wat met hierdie studie ingewin is behoort te lei tot ‘n beter insig en begrip van die chemiese en fisiese eienskappe van die verskeie Nb(V) en Ta(V) komplekse en om moontlike verskille te identifiseer om in die toekoms toe te pas vir die ontwikkeling van metodes vir die skeiding van niobium en tantalum.National Research Foundation (NRF)The World Academy of Science (TWAS)Department of Chemistry, University of the Free Stat
HENDERSON, Charles Lowe Inventory of documents
No full textCOVERAGE 1888-1971; 5 Files; 0,11 Metre.Private papers of C.L. Henderson, Private Secretary for the Minister of Posts and Telegraphs [1925-1929], Labour and Social Welfare [1939], Secretary for the Labour Party [1932-1947], Senator [1939-1948