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Metalation of N‐mesityl‐P,P‐diphenylphosphinic amide with nBuLi in toluene yields tetranuclear lithium N‐mesityl‐P,P‐diphenylphosphinimidate ([Ph2P(OLi)=N−Mes]4, 1). Metalation of Ph2P(O)−N(H)Mes with a mixture of dibutylmagnesium and butyllithium in DME leads to formation of dinuclear [Ph2P{OLi(dme)}=N−Mes]2 (2). Excess of Ph2P(O)−N(H)Mes gives dinuclear [Li(O−PPh2=N−Mes){Ph2P(=O)−N(H)−Mes}]2 (3) with three‐coordinate alkali ions. The metathetical approach via reaction of 1 with anhydrous magnesium bromide in ethereal solution yields [{(thf)LiBr}2{(thf)Li(O−PPh2=NMes)(Et2O)Li(O−PPh2=NMes)}] (4). Heterobimetallic Li/Mg compounds are not accessible by these protocols. Reactions of 1 with DME, with excess of Ph2P(O)−N(H)Mes or with LiBr allows the straightforward conversion to compounds 2, 3 and 4. [ABSTRACT FROM AUTHOR]

A series of thiolate ligands were used to synthesize diiron(I) hexacarbonyl bis(thiolates) for structural studies. Conversion of the corresponding thiols with triiron(0) dodecacarbonyl yields complexes of the type [{(CO)3Fe(μ‐SR)}2] [R = C6H5 (1), C6H4‐4‐CH3 (2), C6H4‐4‐F (3), C6F5 (4), C6H4‐4‐CF3 (5), C6H2‐2,4,6‐(CH3)3 (6), CH2–C6H4‐4‐Cl (7)]. These complexes were isolated and fully characterized, including X‐ray crystal structures of complexes 2–7. The bridging thiolate ligands mainly influence the Fe–CO bond which is trans‐positioned to the second iron(I) center. In solution, the anti‐isomer with one axially and one equatorially oriented thiolate is the major species; severe steric strain induced by mesityl groups only allows the formation of syn‐endo‐isomeric molecules of 7. Furthermore, light‐induced CO release at solid material at the three representative complexes 1, 3, and 6 verify suitability as photoCORMs. [ABSTRACT FROM AUTHOR]

Lithiation of N‐(2,6‐diisopropylphenyl)‐N′‐(2‐pyridylethyl)benzamidine (1) with LiN(SiMe3)2 in a solvent mixture of toluene and TMEDA yields hexameric lithium N‐(2,6‐diisopropylphenyl)‐N′‐(2‐pyridylethyl)benzamidinate (2), which can be purified by recrystallization from a solvent mixture of toluene and THF. The three‐coordinate lithium ions have T‐shaped coordination spheres. The negative charge is delocalized within the 1,3‐diazaallylic system, which adopts a (syn‐Z)‐arrangement. [ABSTRACT FROM AUTHOR]

The condensation reaction of 2,2′‐diamino‐4,4′‐dimethyl‐6,6'‐dibromo‐1,1′‐biphenyl with 2‐hydroxybenzaldehyde as well as 5‐methoxy‐, 4‐methoxy‐, and 3‐methoxy‐2‐hydroxybenzaldehyde yields 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyl (1a) as well as the 5‐, 4‐, and 3‐methoxy‐substituted derivatives 1b, 1c, and 1d, respectively. Deprotonation of substituted 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls with diethylzinc yields the corresponding substituted zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls (2) or zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyls (3). Recrystallization from a mixture of CH2Cl2 and methanol can lead to the formation of methanol adducts. The methanol ligands can either bind as Lewis base to the central zinc atom or as Lewis acid via a weak O–H···O hydrogen bridge to a phenoxide moiety. Methanol‐free complexes precipitate as dimers with central Zn2O2 rings. [ABSTRACT FROM AUTHOR]

Transmetalation of Sn[N(SiMe3)2]2 with calcium granules in tetrahydropyran (thp) yields colorless [(thp)2Ca{N(SiMe3)2}2] ( 1) which is soluble in common organic solvents. The calcium center is in a distorted tetrahedral environment with Ca-N and Ca-O bond lengths of 231.08(11) and 240.23(9) pm, respectively. The molecular structure is dominated by steric factors leading to a NCaN bond angle of 119.43(6)°. [ABSTRACT FROM AUTHOR]