Phosphine-based copper preparation

Thiometallates (8) and Ta6Sn " serve as synthons, for instance, for the preparation of mixed-metal clusters involving iron or copper and silver, respectively. The discrete polynuclear TasSi/" and Nb4Se22 anions, prepared by traditional solid-state routes, have a structure related to that of polynuclear Mo oxysulfide anions. Nb-Cu chalcogenido clusters stabilized by phosphines could be prepared directly from NbCls (equation 8). The anion (9), for instance, is based on two CusNbSsCl heterocubane units linked by three /u.3-chlorine. ... 

A common method used for the preparation of bisphosphinoethanes is the reductive coupling of a methyl phosphine oxide or phosphine borane (Scheme 18) using a strong base and copper salts.27 This process occurs with no racemization of the adjacent phosphorus atom. 

Michael reaction. Different ligands for copper catalysts are available. For example, an oxazoline prepared from valine," a phosphine from proline,"" and a carbohydrate-based thiolhave been tested. 

The 14-membered macrocyclic phosphine 77 and corresponding sulfide 78 were prepared by the macrocyclization under high dilution conditions and further oxidation with sulfur (Scheme 12.29). Both ligands were used as ionophores in an all-solid state poly(vinylchloride) matrix membrane electrode. The sulfide 78 based electrode exhibited a Nemstian response towards copper (II) ions with a cationic slope of 30.7 mV/pCu and a detection limit of 5.97 x 10 M. The potential response remains almost unchanged over the pH range 3.9-6.4 at least 7 months. Sensors based on the macrocycles 77 and 78 demonstrate the copper (11) ion sensitivity over other metal ions [83]. 

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