Amines coordination numbers

The majority of U(V1) coordination chemistry has been explored with the trans-ddo s.o uranyl cation, UO " 2- The simplest complexes are ammonia adducts, of importance because of the ease of their synthesis and their versatihty as starting materials for other complexes. In addition to ammonia, many of the ligand types mentioned ia the iatroduction have been complexed with U(V1) and usually have coordination numbers of either 6 or 8. As a result of these coordination environments a majority of the complexes have an octahedral or hexagonal bipyramidal coordination environment. Examples iuclude U02X2L (X = hahde, OR, NO3, RCO2, L = NH3, primary, secondary, and tertiary amines, py n = 2-4), U02(N03)2L (L = en, diamiaobenzene n = 1, 2). The use of thiocyanates has lead to the isolation of typically 6 or 8 coordinate neutral and anionic species, ie, [U02(NCS)J j)/H20 (x = 2-5). 

In compounds (333) and (336) the amines substitute one of the dithiophosphate ligands to form a NiN4S2 core with the second dithiophosphate ligand serving as a counterion. Coordination number 5 is rare, but is found for complex (345) where one of thiophosphates switched to a monodentate coordination,879 and in compound (346) where only one additional phosphine adduct coordinates to Ni.880... 

Cobalt in its trivalent state forms many stable complexes in solution. In these complexes, the coordination number of Co + is six. The Co2+ ion also forms complexes where the coordination number is four. Several complexes of both the trivalent and divalent ions with ammonia, amines, ethylene diamine, cyanide, halogens and sulfur ligands are known (see also Cobalt Complexes). 

A number of examples of the introduction of the metal onto the support have already been mentioned in the previous section either because one of the ligands coordinated to the metal became part of the polymer [see reactions (4) and (18)—(20)] or because the metal complex reacted directly with the support [reactions (1) and (2)] or because the preparation simply involved sorption by van der Waals forces onto the support (Section I). In the present section, we shall be particularly concerned to introduce metal complexes onto polymeric supports that have typical donor groups such as tertiary phosphine and amine. A number of routes, most of which are of fairly general applicability, have been used. 

Gmelin Handbook Volumes on Boron and its Compounds (a) Main Volume (1926) (b) Supplement vol. 1 (1954) (c) Compounds 8 (NSSV 33), The tetrahydroborate ion and its derivatives (1976) (d) Compounds 9 (NSSV 34), Boron-halogen compounds , Part 1 (1976) (e) Compounds 10 (NSSV 37), Boron compounds with coordination number 4 (1976) (f) Compounds 15 (NSSV 46), Amine-boranes (1977) (g) Compounds 19 (NSSV 53), Boron-halogen compounds , Part 2 (1978) (h) Supplement Volumes (1980-82), Springer-Verlag, Berlin. 

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