Amines platinum group metals

Catalytic Reductive Alkylation of Aromatic and Alkyl Amines and Diamines over Sulfided and Unsulfided Platinum Group Metals... 

Secondary amines synthesized by catalytic reductive alkylation of primary amines are used in a variety of fine and specialty chemical indnstries. For example, derivatives of cyclohexylamine are used as corrosion inhibitors, N-(l,3-dimethylbntyl)-N -phenyl-p-phenylenediamine (6-PPD) is nsed as an anti-oxidant in rabber indnstiy, several dialkylated diamines are used in the coatings indnstiy, while they are nsed in the pharmacentical industry as pharmacophores (1-7). Harold Greenfield and co-workers have examined the ability of platinum group metals (PGM), base metals, and their snlfides to catalyze rednctive alkylation of primary and secotrdary amines (8-11). They found that different catalysts are optimal for the... 

Kramer, J. Driessen, W. L. Koch, K. R. Reedijk, J. Highly selective extraction of platinum group metals with silica-based (poly)amine ion exchanges applied to industrial metal refinery effluents. Hydrometallurgy 2002, 64, 59-68. 

Olefins - [FEEDSTOCKS - COALCHEMICALS] (Vol 10) - [FEEDSTOCKS-PETROCHEMICALS] (VollO) - [HYDROCARBONS - SURVEY] (Vol 13) -m automobile exhaust [EXHAUSTCONTROL, AUTOMOTIVE] (Vol 9) -catalyst for stereospeafic polymerization [TITANIUMCOMPOUNDS - INORGANIC] (Vol 24) -esters from [ESTERIFICATION] (Vol 9) -hydroxylation using H202 [HYDROGEN PEROXIDE] (Vol 13) -luminometer ratings [AVIATION AND OTHER GAS TURBINE FUELS] (Vol 3) -osmium oxidations of [PLATINUM-GROUP METALS, COMPOUNDS] (Vol 19) -polymerization [SULFONIC ACIDS] (Vol 23) -reaction with EDA [DIAMINES AND HIGHER AMINES ALIPHATIC] (Vol 8) -silver complexes of [SILVER COMPOUNDS] (Vol 22)... 

The use of amine salts in the commercial solvent extraction of the platinum-group metals from chloride solutions is described in Section 63.3.2.5. 

In extension to the dehydrogenation studies of amine boranes and the transfer hydrogenations of alkenes catalyzed by the Re(I) complexes 16 and 17, highly efficient hydrogenations of alkenes were established based on the co-catalytic systems of 16/Me2NH-BH3 or 17/Lewis acid, which exhibited catalytic activities comparable to those of Wilkinson- or Schrock-Osbom-type hydrogenations accomplished with platinum group metal catalysts [24]. 

The catalyst for the oxidative carbonylation to give PhNHCOOEt was metallic palladium with iodide compounds as promoters [11]. The selectivity was superior to 97 %, with a turnover of 300 g/g Pd h. Other platinum group metals, particularly rhodium, were active, although less efficient as catalysts [12], The reaction is conducted under 80 atm of CO and 6 atm of O2 at 160-170 °C and can also be applied to aliphatic amines. Diphenylurea is intermediately formed. 

Solvent extraction is proposed as a suitable method for PGMs (platinum group metals) recovery from low concentrated sources. Several extractants have been studied and proposed, e.g., hydroxyoximes, alkyl derivatives of 8-hydroxyquinoline, dialkyl sulphides, hydrophobic amines and quaternary ammonium salts, derivatives of pyridine and pyridinecarboxamides. However, the problems of a slow extraction rate or low metal separation remain to be solved. Looking for extractants permitting possibly fastest extraction of Pd, two phosphonium ionic liquids, i.e., [QP][C1] and [QP][Bis], have been used (Cieszynska et al., 2007 Cieszynska, 2010 Cieszynska Wisniewski, 2010, 2011). To overcome problems caused by the high viscosity of ILs, the mixtures with toluene have been used for extraction, similarly as for extraction of Zrf+. 

Catalysts used for preparing amines from alcohols iaclude cobalt promoted with tirconium, lanthanum, cerium, or uranium (52) the metals and oxides of nickel, cobalt, and/or copper (53,54,56,60,61) metal oxides of antimony, tin, and manganese on alumina support (55) copper, nickel, and a metal belonging to the platinum group 8—10 (57) copper formate (58) nickel promoted with chromium and/or iron on alumina support (53,59) and cobalt, copper, and either iron, 2iac, or zirconium (62). 

Other Amines.—Many compounds of copper, mercury, silver, gold, and the metals of the platinum group are known, which admit of representation in a similar manner. They differ, however, inasmuch as the metal must be considered to have replaced more than one atom of hydrogen in one molecule of ammonium. Thus we have ... 

The substitution reactions of amine platinum(IV) complexes is appreciably slower than those of most other inert metal amines, at least in acidic solutions. Consequently, the availability of a relatively labile leaving group, such as trifluoro-methanesulfonate, may have advantages where substitution is required at the sixth site about the pentaammineplatinum(IV) ion. In parallel with reports of other second- and third-row complexes in this chapter, the synthesis of [Pt(NH3)5(0S02Cp3)] from the [Pt(NH3)5Cl]Cl3 precursor is readily achieved. Both are described below. 

The most spectacular results, in terms of comparison between CFPs- and carbon-supported metal catalysts, were likely provided by Toshima and co-workers [33,34]. As illustrated in Section 3.3.3, they were able to produce platinum and rhodium catalysts by the covalent immobilization of pre-formed, stabilized metal nanoclusters into an amine functionalized acrylamide gel (Scheme 5). To this purpose, the metal nanopartides were stabilized by a linear co-polymer of MMA and VPYR. The reaction between its ester functions and the amine groups of the gel produced the covalent link between the support and the... 

NMR measurements are very useful to understand the properties of the stabilizing reagents of metal nanoparticles. Author s group reported the structure of stabilization of non-ionic and cationic surfactants on platinum nanoparticles [22] and that of ternary amines on rhodium nanoparticles [23]. Such information is considerably important for applications of nanoparticles such as... 

Although a wide variety of metals were claimed as active catalysts for formaldehyde hydrophosphination, platinum salts were preferred. Similarly, Group 10 metal salts were used to catalyze acrylonitrile hydrophosphination. Russian workers showed that Ni(II) or Co(II) salts in the presence of ammonia or amines would also catalyze the addition of phosphine to formaldehyde [6]. More recently, academic and industrial interest in these reactions was sparked by a series of papers by Pringle, who investigated late metal phosphine complexes as hydrophosphination catalysts. These and related studies are arranged below by substrate. 

When coordinated to metal ions in their normal or higher oxidation states, an isocyanide is rendered susceptible to attack at the ligating carbon atom by nucleophilic reagents.1 When alcohols or amines are the nucleophiles, carbene complexes that may be prepared for a variety of metals and substituent groups are obtained. The first fully characterized compounds were of platinum(H),2 and general methods of their preparation, with particular examples, are given below. 

The hydrocarboxylation reaction of alkenes and alkynes is one which utilizes carbon monoxide to produce carboxylic acid derivatives. The source of hydrogen is a protic solvent (equation 35) dihydrogen is not usually added to the reaction. There are a number of variations to this reaction, since the solvent can be water, alcohols, amines, acids, etc. The catalysts can be Group VIII-X transition metals, but cobalt, rhodium, nickel, palladium and platinum have found the most use. 

---