The reaction between the tertiary phosphine-borane PhP­(BH3)­(CH2Ph)2 (6) and 1 equiv of nBuLi, PhCH2Na, or PhCH2K gives the monodeprotonation products [PhP­(BH3)­(CHPh)­(CH2Ph)]­ML n (ML n = Li­(OEt2)0.25 (7), Na­(THF)0.5 (8), K­(OEt2)0.5 (9)). Similarly, the reaction between 6 and 2 equiv of either PhCH2Na or PhCH2K gives the 1,3-dicarbanion complexes [PhP­(BH3)­(CHPh)2]­[ML n ]2 (ML n = Na­(THF) (10), K­(THF)0.25 (11)). However, the reaction between 6 and 2 equiv of nBuLi in Et2O, THF, or nBu2O gives a mixture of mono- and dimetalated products. Unexpectedly, the reaction between 6 and 3 equiv of nBuLi in diethyl ether in the presence of silicone grease gives the trinuclear cluster [PhP­(BH3)­(CHPh)2]­Li3­(OSiMe2­CH2CH2­CH2CH3)­(OEt2)3 (12); this compound may be isolated in essentially quantitative yield from the reaction between 6, hexamethyltrisiloxane, and nBuLi in a 3:1:9 ratio. Similar tri-lithium complexes are isolated from the reaction between 6 and 3 equiv of nBuLi in Et2O or tBuOMe, which yields [PhP­(BH3)­(CHPh)2]­Li3(OEt)­(OEt2)3 (13) and [PhP­(BH3)­(CHPh)2]­Li3­(OMe)­(OtBuMe)3 (14), respectively. The reaction between 6, 2 equiv of nBuLi, and 1 equiv of in situ generated LiOEt or LiOiPr gave the tri-lithium clusters 13 and [PhP­(BH3)­(CHPh)2]­Li3­(OiPr)­(OEt2)3 (16), respectively.

Metalation of tBu 2 PH(BH 3 ) (1H), iPr 2 PH(BH 3 ) (2H), iPrPhPH(BH 3 ) (3H), Ph 2 PH(BH 3 ) (4H) or (Mes) 2 PH(BH 3 ) (5H) with one equivalent of nBuLi in either diethyl ether or THF gave the corresponding phosphido-borane complexes, which were obtained as single crystals of the solvates [{tBu 2 P(BH 3 )}Li, and [{(Mes) 2 P(BH 3 )}Li(THF) 2 ] 2 (5Li) after crystallization from diethyl ether; the alternative adduct [{Ph 2 P(BH 3 )} Li(TMEDA)] ∞ (4Li(TMEDA)) was isolated from the reaction of 4Li with TMEDA. Similar metalation reactions between 1H, 2H or 4H and PhCH 2 Na gave the complexes [{tBu 2 P(BH 3 )}Na(THF)] ∞ (1Na) and [{iPr 2 P(BH 3 )}Na(THF)] ∞ (2Na), and [{Ph 2 P(BH 3 )}Na-(TMEDA)(THF)] ∞ (4Na(TMEDA)). Compounds 1Li, 2Li, 3Li, 4Li and 4Li(TMEDA) crystallize as zig-zag polymers, while 5Li crystallizes as a centrosymmetric dimer; compounds 1Na and 2Na crystallize as ribbon polymers, although these differ significantly in structure, while 4Na(TMEDA) crystallizes as a zig-zag polymer.

The number of methods to study transient paramagnetic hydrides at organometallic centres is extremely limited. The reactivity of {2Fe2S} centres with protons to produce both diamagnetic and paramagnetic systems is of central interest in developing novel catalysts for hydrogen production, inspired by the [FeFe]-hydrogenase enzymes. Here, we show how a combination of spectroscopic and electrochemical techniques is allowing access to detail of the reactivity of key species on these pathways. Electron paramagnetic resonance and infra-red spectroelectrochemical approaches have been used to observe the reduction of pre-generated diamagnetic hydrides. In contrast, avoided level crossing muon spin resonance (ALC-µSR) has been used to form the open-shell species directly and to examine the formation of short-lived intermediates in the reaction process. The combination of these techniques suggests the involvement of terminal hydrides or CO-protonation states on the pathway to the isolable bridging hydride products.

A new ligand containing a N 2 S donor set of atoms has been prepared using Click Chemistry from the reaction of 1,3,4-thiadiazole-2,5-dithiol dipotassium salt with propargyl bromide followed by the addition of the product formed from the reaction of sodium azide and octyl iodide, using Cu(I) as catalyst. The ligand was characterized using FT-IR, UV-Vis, 1 H, 13C NMR spectroscopes and C, H, N elemental analysis. The corresponding Co(II), Ni(II) and Cu(II) complexes were characterized by FT-IR, UV-Vis spectroscopes as well as conductivity and magnetic susceptibility measurements. These measurements suggest that the geometry around the Co is tetrahedral, while around the Ni and Cu it is distorted octahedral. The solubility's of the ligand and its complexes were measured in different solvents.