A series of lanthanide complexes bearing organic radical ligands, [Ln(Cp)(bipy·)] [Ln = La, Cp = Cp (1); Ln = Ce, Cp = Cp (2); Ln = Ce, Cp = Cp″ (3); Ln = Ce, Cp = Cp‴ (4)] [Cp = {CHBu-1,3}; Cp″ = {CH(SiMe)-1,3}; Cp‴ = {CH(SiMe)-1,2,4}; bipy = 2,2'-bipyridyl], were prepared by reduction of [Ln(Cp)(μ-I)] or [Ce(Cp‴)(I) (THF)] with KC in the presence of bipy (THF = tetrahydrofuran). Complexes 1-4 were thoroughly characterized by structural, spectroscopic, and computational methods, together with magnetism and cyclic voltammetry, to define an unambiguous Ln(III)/bipy· radical formulation. These complexes can act as selective reducing agents; for example, the reaction of 3 with benzophenone gives [{Ce(Cp")(bipy)}{κ-O,O'-OPhC(CH)CPhO}] (7), a rare example of a "head-to-tail" coupling product. We estimate the intramolecular exchange coupling for 2-4 using multiconfigurational and spin Hamiltonian methods and find that the commonly used Lines-type isotropic exchange is not appropriate, even for single 4f e/organic radical pairs.

The substituted cyclopentadienyl group 1 transfer agents KCp 00 , KCp 0 0 0 and KCp tt (Cp 00 = {C 5 H 3 (SiMe 3 ) 2 -1,3} À ; Cp 0 0 0 = {C 5 H 2 (SiMe 3 ) 3 -1,2,4} À ; Cp tt = {C 5 H 3 ( t Bu) 2 -1,3} À ) were prepared by modification of established procedures and the structure of [K(Cp 00 )(THF)] N ÁTHF (1) was obtained. KCp 00 and KCp tt were reacted variously with [Ln(I) 3 (THF) 4 ] (Ln = La, Ce) in 2 : 1 stoichiometries to afford monomeric [La(Cp 00 ) 2 (I)(THF)] (2aÁTHF) and the dimeric complexes [La(Cp 00 ) 2 (m-I)] 2 (2a), [Ce(Cp 00 ) 2 (m-I)] 2 (2b) and [Ce(Cp tt ) 2 (m-I)] 2 (3). KCp 0 0 0 was reacted with [Ce(I) 3 (THF) 4 ] to afford the mono-ring complex [Ce(Cp 0 0 0 )(I) 2 (THF) 2 ] (4), regardless of the stoichiometric ratio of the reagents. Complex 4 was reacted with [KN(SiMe 3 ) 2 ] to yield [Ce(Cp 0 0 0 ) 2 (I)(THF)] (5), [Ce(Cp 0 0 0 ){N(SiMe 3 ) 2 } 2 ] (6) and [Ce{N(SiMe 3 ) 2 } 3 ] by ligand scrambling. Complexes 1-6 have all been structurally authenticated and are variously characterised by other physical methods.

F 8 (O 2 C t Bu) 16 ] is reported using tetramethylammonium hydroxide pentahydrate as the source of a template, where M = Zn, Mn, Ni, and Co. The metal cores are octagons with metal−metal edges bridged by one fluoride and two carboxylate ligands. The divalent metal ions are found ordered at positions 1 and 5 in the octagon. The tetramethylammonium cations are above and below the metal plane of the ring in the crystal structure. Magnetic studies show antiferromagnetic coupling between the paramagnetic metal ions present, leading to paramagnetic ground states in each case. 1 H NMR spectroscopy confirms that the structure of the {Cr III 6 Co II 2 } ring exists in solution, and electron paramagnetic resonance spectroscopy confirms the magnetic structure of the other three rings.

A finite chain of thirty‐one paramagnetic centers is reported, synthesized by reaction of hydrated chromium fluoride, copper carbonate and pivalic acid in the presence of 1,4,7,10‐tetrazacyclododecane (cyclen). Magnetic studies show predominantly anti‐ferromagnetic exchange leading to a high density of low‐lying spin states and large saturation field.

The racemic ligand (±)-tris-(4-methylthiazolyl)cyclotriguaiacylene forms a homochiral crystalline Ag12L8 cube with spontaneous resolution. The ligand itself likewise crystallises in a chirally pure fashion in two clathrate complexes. Ag12L8 is the first example of a cyclotriguaiacylene-type coordination cube and a rare example of a M12L8-type metallo-cube.