IB Metals Research Articles

New sulphinate complexes of the Group IB metals and their oxidation by molecular oxygen

Summary The preparation of some sulphinate complexes of the Group IB metals is reported, and the reaction of the complexes with molecular oxygen has been studied.

Crystal growth of metallic sulfides by thermal treatment in sulfuretted hydrogen atmosphere

The crystal growth of simple or mixed sulfides of the metals of the IB (Cu-Ag) and IIB (Zn-Cd-Hg) groups by thermal treatment in sulfuretted hydrogen atmosphere is studied by means of scanning electron microscope. The kinetics of the crystal growth varies very much from one group of sulfides to the other because of the large difference between their thermodynamic properties. The crystallisation is easy and fast for the sulfides of the metals of the IB group. It is slow and the crystals obtained are small for the sulfides of the metals of the IIB group. Mixed sulfides containing two IB metals or two IIB metals are reduced to the case of the simple sulfides whereas mixed sulfides containing both one IB metal and one IIB metal have a very particular behaviour. The physical factors which seem to take place directly in the crystal growth are investigated.

Group IB metal chemistry. Part I. Preparation and reactions of the carbonyl(hydrotripyrazol-1-ylborato)copper(I) complex

The reaction between copper(I) chloride and K[HB(pz)3](pz = pyrazol-1-yl) in the presence of CO affords white, crystalline [{HB(pz)3}Cu(CO)](I) as an air- and heat-stable copper carbonyl complex. Reactions between (I) and ligands L [L = PPh3, PMePh2, P(OMe)3, P(OPh)3, Ph2PCH2CH2PPh2(dppe), AsPh3, SbPh3, or ButNC] afford the complexes [{HB(pz)3}CuL]. On heating, (I) first decarbonylates to [Cu2{HB(pz)3}2](II) which then disproportionates to copper metal and Cu[HB(pz)3]2.

Immiscibility in binary alloys of group IB metals (copper, silver and gold) ? a semi empirical approach

The paper shows that concepts of neither the Hildebrand parameter nor the Mott number are adequate to predict the occurrence of miscibility gaps in binary metallic systems. It shows that modified versions of these parameters which are closely integrated with the structure of liquid metals (now called the Kumar-Hildebrand and the miscibility syndrome respectively), statistically account for the occurrence of miscibility gaps. Whereas no rigorous and theoretical justification could be given, it is shown that miscibility in liquid binary metallic systems could be discussed in terms of the electronic configuration of valency electrons.

Stabilities of the cyanide complexes of the monovalent group IB metal ions in aqueous solution

Potentiometric methods have been used to determine stability constants for the cyanide complexes of Cu(I), Ag(I) and Au(I) in aqueous solution. For Cu(I) the constants determined were log β 2 = 21·7, log β 3 = 26.8 and log β 4 = 27·9, and for Ag(I), log β 2 = 20·9 and log β 3 = 21·8. For Au(I), E 0 for Au(CN) 2 − was found to be −0·50V, which was combined with a previous estimate of the Au +(aq)/Au(s) standard reduction potential (+1·668V) to give log β 2 = 36·6.

Chemistry of azido complexes of Group Ib metals

Chemistry of azido complexes of Group Ib metals

The Structure and Catalytic Properties of Palladium-Silver and Palladium-Gold Alloys

Abstract The great differences between the catalytic activities of the Group VIII and the Group IB metals have attracted much attention, especially over the last 25 years, and explanations of these differences have been sought through studying the manner of activity variation in alloys formed between suitable pairs of metals. Selection of suitable alloy systems has presented difficulties. Most work has naturally been done on systems exhibiting a continuous range of solid solution, and hence Pt-Au and Pt-Ag alloys, both of which have miscibility gaps, have not been widely studied. Much work has been done on Ni-Cu alloys, but recent results have demonstrated the presence of phase separation in this system, and this has called into question the interpretation of the earlier work. The Pd-Ag and Pd-Au systems appear to have complete miscibility, and have consequently been much studied: it is to them that this review is directed.

Complex Temperature Dependencies of the Rate of Carbon Deposition on Nickel

ALTHOUGH the properties of carbon formed from hydrocarbons on catalytic metal surfaces have received some attention, the kinetics of the deposition have not been studied in detail. We have carried out a study of the deposition from light hydrocarbons in the C1–C4 range, on various group VIII and IB metals. The results reported here concern some aspects of the kinetics of the deposition from unsaturated hydrocarbons on nickel.

Synthetic Reactions by Complex Catalysts. XIV. Reaction of Isocyanide with Amine Catalyzed by Group IB and IIB Metal Compounds

Abstract Group IB and IIB metal compounds catalyze the reaction of isocyanides (1) with amines (2) producing formamidines (3). In the reaction of cyclohexyl isocyanide with piperidine, the accelerating effect of catalyst was in the order AgCl>CuCl>>ZnCl2, Cd(OAc)2, HAuCl4·4H2O. The AgCl catalyzed reaction proceeded almost quantitatively in 2.5 hr at 17°C. The reaction of aliphatic isocyanide with aromatic amine, e.g., N-methylaniline, required higher reaction temperatures (160°C) even in the presence of catalyst, in which the order of catalytic activity was HAuCl4·4H2O>ZnCl2>AgCl>>CuCl. A ternary complex of (CuCl)2 (cyclohexyl isocyanide)2 (piperidine) was isolated, which was unstable and decomposed gradually at room temperature to give N-cyclohexyl-N,N′-pentamethylene formamidine. A mechanism through a mixed ligand complex has been proposed, in which both isocyanide and amine are coordinated with the same metal ion and the reaction takes place in the sphere of complex ligand.

Synthetic Reactions by Complex Catalysts. XIII. Carbonylation of Amines by Group IB and IIB Metal Compound Catalysts

The present investigation was undertaken in order to examine the catalytic activities of Group IB and IIB metal compounds in the carbonylation of aliphatic and aromatic amines with carbon monoxide, and in order to compare the catalyst activities with those of other metal compounds. It was found that: i) copper compounds are excellent catalysts for the carbonylation of aliphatic amines to produce the corresponding formamides; ii) the catalytic activities of copper compounds are enhanced by the addition of water; and iii) chloroauric acid catalyzes the carbonylation of aromatic amine, whereas copper compounds do not. The temperature effects on the carbonylation of morpholine were also examined.

Synthetic Reactions by Complex Catalysts. IX. Reaction of Thiol with Isocyanide

Abstract The reaction of a thiol with an isocyanide proceeds in two directions. In the first reaction (course a), the carbon atom of isocyanide with lone-pair electrons is inserted into the sulfur-hydrogen bond of thiol to produce thioformimidate (I). In the second reaction (course b), isothio-cyanate (II) and the alkane (III) from the alkyl group of thiol are formed. The proportion of the participation of two reactions depends upon the alkyl group of thiol and upon the reaction conditions including whether or not a catalyst is employed. Primary thiol prefers course a to course b, whereas tertiary thiol prefers course b. In the reactions at 15°C, the Group IB and IIB metal compounds, e. g., copper compounds, catalyzed the course a reaction preferably. At higher temperatures, e. g. at 100°C, thiol reacts with isocyanide quite rapidly, even in the absence of a catalyst. However, the catalyst effect favoring course a is seen even in the high-temperature reactions. The mechanism of the reaction, especially course b, has been discussed. Syn-anti structures of thioformimidate were also studied by NMR.

The Microcatalytic Hydrogenation of Benzene over Groups VIII and Ib Metals and Alloys

The Microcatalytic Hydrogenation of Benzene over Groups VIII and Ib Metals and Alloys

Coordination compounds of Group IB metals. I. Triethylphosphine complexes of gold(I) mercaptides

Various triethylphosphine coordinated gold(1) mercaptides of formula Et3PAuSR (R = Me, Et, Pr, Bu, Bu1, Ph, CH2Ph, β-C10H7, and CH2CH(NH2)C02H), and related sulphur derivatives of formula Et3PAuY (Y = SCN, SC(S)Net2, SC(S)OEt, and SC(NH2)NH2+Br-) have been prepared. Under appropriate conditions, displacement of the sulphur group from the gold atom is observed, either by another sulphur nucleophile, e.g. Et3PAuSR + Et2NCSS- → Et3PAuSC(S)Net2 + RS-, or by a. nucleophile such as Cl-, Br-, I-, NO3-, or CN-.

Coordination compounds of Group IB metals. IV. Triethyl- and triphenyl-phosphine complexes of aurous alkyl xanthates

The preparation of new compounds in the series Et3PAuSC(S)OR (R = Me, Pr, Pr1, Bu, Bus, pentyl) and Ph3PAuSC(S)OR (R = Me, Et, Pr, Pr1) is described. The compound (Ph3P)2AgSC(S)OEt was also prepared.

Coordination compounds of Group IB metals. II. Some tertiary phosphine and phosphite complexes of gold(I)

Gold(1) complexes of type R3AuX (R = Bu, Ph; X = Cl, Br, SCN), complexes Ph3PAuSR (R = alkyl, aryl), Ph3PAuEt, (PhO)3PAuCl, and bis(phosphine) complexes of type [R3PauPR3]+X- (R = Et, Ph; X = Cl, Br, SCN) are described. Triphenyl phosphite complexes were very unstable; attempts to prepare triethyl phosphite complexes were unsuccessful. A triethylphosphine complex of aurous sulphide, Et3PauSAuPEt3, and a sulphonium complex, [(Ph3PAu)3S]+Cl-, were also prepared.

Coordination compounds of Group IB metals. III. Triethyl- and triphenylphosphine complexes of cuprous, argentous, and aurous NN-dialkyldithiocarbamates

Triethylphosphine and triphenylphosphine complexes of various NN- dialkyldithiocarbamates of gold(1), silver(1), and copper(1) are described, of formulae (I; R = Et; R' = Pr); (111; M = Ag, Cu; R' = Me, Et, Pr, Bu); and (IV; M = Ag, Cu; R' = Me, Et, Pr, Bu). Certain complexes of formula (1) are unstable, and lose the phosphine moiety during attempted preparation. Complexes (111) and (IV) are prepared by reaction of the appropriate metal dithiocarbamate with triethyl- or triphenyl-phosphine respectively. Complexes (111; M = Ag, Cu; R' = Et) gave monomeric molecular weights in chloroform solution, but the apparent molecular weights of complexes (IV; M = Ag, Cu; R' = Et) indicated extensive dissociation in both chloroform and benzene. The present evidence suggests an ionic dissociation in the sense (Ph3P)2M+ R2NCSS-. An improved preparation of cuprous NN-dialkyldithiocarbamates is given.

Magnetic Order in Rare-Earth Intermetallic Compounds

Neutron diffraction measurements were made on a series of rare-earth intermetallic compounds to determine the type of magnetic order and its relationship to the number of valence electrons in the system. The compounds studied included TbCu, TbZn, TbGa, TbAg, TbHg, and TbIn. The compounds with Cu, Zn, Ag, and Hg were found to have the CsCl-type structure, TbGa the CrB-type structure, and TbIn a complex tetragonal unit cell. TbGa is ferromagnetic with a Curie temperature of 155\ifmmode^\circ\else\textdegree\fi{}K, while TbIn is antiferromagnetic below 190\ifmmode^\circ\else\textdegree\fi{}K. For the compounds with the CsCl structures, TbCu and TbAg are antiferromagnetic with N\'eel temperatures of 115 and 100\ifmmode^\circ\else\textdegree\fi{}K, while TbZn and the TbHg are ferromagnetic below 160 and 80\ifmmode^\circ\else\textdegree\fi{}K, respectively. This difference is magnetic behavior of the compounds with group Ib and IIb metals must be associated with the number of valence electrons rather than with interatomic separations because the lattice constants of the two groups overlap.

Heats of Solution of Group IB Metals in Liquid Tin

An isothermal calorimeter suitable for measurements of heats of solution in liquid tin as solvent is described. Measurements of the heats of solution of gold, silver, copper, and a gold-silver alloy are reported. The heat of formation of this gold-silver alloy is also reported.