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1.
Dalton Trans ; 43(45): 16959-73, 2014 Dec 07.
Article in English | MEDLINE | ID: mdl-25325879

ABSTRACT

Exciting new variations in Fischer-type carbene complex composition and reactivity have been realised by following or modifying well-established synthetic approaches such as metal carbonyl functionalization and modification of existing carbene ligands. The formation of targeted complexes for organic synthesis, carbene-containing chelates, and polynuclear carbene complexes, by employing 'click chemistry', warrants discussion. Transmetallation and α,α-dehydrogenation of ethers and amines have come into their own as viable synthetic methods to access carbene complexes with unique properties and activities. Successful mediation of carbene complex formation with pincer ligands has proved its worth. Quantum chemistry has become essential for supporting or initiating mechanistic proposals, but heuristic approaches such as invoking the vinylology principle to describe substituted phenylcarbene complexes are still valuable in the interpretation of bonding properties and the classification of complex types. Electrochemical studies now also constitute a powerful part of the experimental characterization tool kit.

2.
Appl Radiat Isot ; 72: 96-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23208238

ABSTRACT

The production of (82)Sr at iThemba LABS is performed by the proton bombardment of a RbCl target using the facility's Vertical-Beam Target Station (VBTS). (82)Sr is separated from the target material using a method based on target dissolution, using dilute ammonium chloride solution, and the use of chromatographic methods on Purolite S950 ion exchange resin. After performing a further purification step using AG MP-50 macroporous cation exchange resin, the result is a product with a high radionuclidic purity and negligible Rb and Fe impurity content.

3.
Appl Radiat Isot ; 69(5): 727-31, 2011 May.
Article in English | MEDLINE | ID: mdl-21334903

ABSTRACT

Cyclotron-produced (68)Ge can be separated from its Ga target material by dissolving the target in aqua regia and collecting the volatile (68)Ge in a solution containing 1.0M NaOH and 2% Na2SO3. The solution is then acidified with HF before being loaded onto a column containing AG MP-1 anion exchange resin. The column is rinsed with dilute HF to remove any remaining impurities, before eluting the desired product with 0.1M HCl. A radiochemically pure product is obtained.

4.
Dalton Trans ; (24): 4646-52, 2009 Jun 28.
Article in English | MEDLINE | ID: mdl-19513472

ABSTRACT

Competitive transport experiments involving metal ions from an aqueous source phase through a chloroform membrane into an aqueous receiving phase have been carried out using a series of N-(thio)phosphorylated (thio)amide and thiourea ligands as ionophores in the organic phase. The source phase contained equimolar concentrations of Co(II), Ni(II), Cu(II), Zn(II), Ag(I), Cd(II) and Pb(II) with the source and receiving phases being buffered at different pH. Good transport properties were observed for Ag(I) in the case of (13). The best extraction properties have been shown by (3)L(1), (3)L(8), (2)L(7), (3)L(9) and (3)L(11) which contain an unsubstituted nitrogen atom at the C[double bond, length as m-dash]S groups ((3)L(1) and (3)L(9)), or a third nitrogen atom, capable of participating in additional coordination ((3)L(8), (2)L(7) and (3)L(11)). Reaction of Cu(NO(3))(2).6H(2)O with the potassium salt of the N-thiophosphorylated thiourea NH(2)C(S)NHP(S)(OiPr)(2) formed a new supramolecular Cu(I) complex, [{Cu(6)((2)L(1))(6)}{Cu(3)((2)L(1))(3)}.4Me(2)CO] that contains both trinuclear and hexanuclear forms in its solid state structure, and in solution.

5.
Appl Radiat Isot ; 67(7-8): 1320-3, 2009.
Article in English | MEDLINE | ID: mdl-19299156

ABSTRACT

The cyclotron production of (88)Y at iThemba LABS is performed via the reaction (88)Sr(p,n)(88)Y. The yields obtained were inconsistent with nuclear data obtained from the literature and the excitation function of the nuclear reaction was re-measured, using a differentiation of thick-target production rate measurements. Ion exchange chromatographic methods are described to separate (88)Y from (nat)Sr target material using AG MP-1 resin and AG 50W-X4 resins, respectively.

6.
Acta Crystallogr C ; 57(Pt 9): 1056-9, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11588370

ABSTRACT

The crystal and molecular structures of bis(eta(5)-2,4,7-trimethylindenyl)cobalt(II), [Co(C(12)H(13))(2)], (I), and rac-2,2',4,4',7,7'-hexamethyl-1,1'-biindene, C(24)H(26), (II), are reported. In the crystal structure of (I), the Co atom lies on an inversion centre and the structure represents the first example of a bis(indenyl)cobalt complex exhibiting an eclipsed indenyl conformation. The (1R,1'R) and (1S,1'S) enantiomers of the three possible stereoisomers of (II), which form as by-products in the synthesis of (I), cocrystallize in the monoclinic space group P2(1)/c. In the unit cell of (II), alternating (1R,1'R) and (1S,1'S) enantiomers pack in non-bonded rows along the a axis, with the planes of the indenyl groups parallel to each other and separated by 3.62 and 3.69 A.

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