Randolf D. Köhn

Synthesis and structure of Fe[C5(CH2Ph)5]2 and Lu(C8H8)[C5(CH2Ph)5]

Abstract The crystal structures of decabenzylferrocene, Fe[C 5 (CH 2 Ph) 5 ] 2 ( 1 ), obtained from FeCl 2 and LiC 5 (CH 2 Ph) 5 at low temperature and (cyclooctatetraenyl)(pentabenzylcyclopentadienyl)lutetium, Lu(C 8 H 8 )[C 5 (CH 2 Ph) 5 ] ( 2 ), obtained from (C 8 H 8 )LuCl(thf) and KC 5 (CH 2 Ph) 5 ( 3 ), have been determined. 1 crystallizes in the space group P 2 1 / c with a 1388.5(2), b 2213.1(6), c 2373.0(3) pm, β 103.50(1)°, and V = 7.0905 × 10 6 pm 3 . Solution of the structure led to final values of R = 0.043 (unit weights) for 11181 observed reflections with F o ≥ 6σ( F o ). Crystals of 2 belong to the space group P 2 1 / a . The unit-cell parameters for 2 are a 1799.0(2), b 1030.2(1), c 1902.3(2) pm, β 97.41(1)°, V = 3.4962 × 10 6 pm 3 with final values of R = 0.021 and R w = 0.030 for 7453 observed reflections with F o ≥ 3σ( F o .

The chemistry of 1,3,5-triazacyclohexane complexes 5: cationic zinc(II) alkyl complexes of N-alkylated 1,3,5-triazacyclohexanes and 13-benzyl-1,5,9-triazatricyclo[7.3.1.05,13]-tridecane

Abstract Diethylzinc reacts with hydroperchlorates of N-alkylated 1,3,5-triazacyclohexanes (R 3 TAC; R = methyl (Me), benzyl (Bz), isopropyl ( i Pr)) and with the hydrotetrafluoroborate of 1,3,5-tris-( para -fluorobenzyl)-1,3,5-triazacyclohexane (FBz 3 TAC) to give the corresponding cationic zinc ethyl complexes [(R 3 TAC)Zn(Et)][X] (X = ClO 4 − , BF 4 − ). Similar complexes were obtained from diethylzinc treated with [HNMe 2 Ph][BF 4 ] or [HNMe 2 Ph][B(C 6 F 5 ) 4 ](Et 2 O) in the presence of R 3 TAC (R = Bz, FBz, s-1-phenylethyl (s-PhMeCH)). A product of decomposition of [(Bz 3 TAC)Zn(Et)][ClO 4 ] was analyzed by X-ray diffraction. The structures of [({s-PhMeCH} 3 TAC)Zn(Et)][BF 4 ] an [(FBz 3 TAC)Zn(Et)][BF 4 ] were estimated using nuclear Overhauser enhancement spectroscopy. Protonolysis of diethylzinc with [HNMe 2 Ph][BF 4 ] in the presence of 13-benzyl-1,5,9-triazatricyclo[7.3.1.0 5,13 ]-tridecane (BzTATC) yielded the complex [(BzTATC)Zn(Et)][BF 4 ].

η3-1,3,5-triazacyclohexane complexes of tribenzylchromium(III)

Abstract 1,3,5-Tribenzyl-1,3,5-triazacyclohexane (‘Bz3TAC’) and 1,3,5-tricyclohexyl-1,3,5-triazacyclohexane (‘Cy3TAC’) react with CrCl3(THF)3 to the corresponding complexes (Bz3TAC)CrCl3 (1a) and (Cy3TAC)CrCl3 (1b). These react with benzyl sodium in toluene to the tribenzylchromium(III) complexes (Bz3TAC)Cr(CH2Ph)3 (2a) and (Cy3TAC)Cr(CH2Ph)3 (2b). The crystal and molecular structure of 2b · 1.5 toluene has been determined by X-ray diffraction.

The chemistry of 1,3,5-triazacyclohexane complexes, 7 synthesis and structure determination of ethyl(-1,3,5-tribenzyl-(−1,3,5-triazacyclohexane)) zinc(II)-hexafluorophosphate

Abstract Diethylzinc reacts with the hydrohexafluorophospate salt of 1,3,5-tribenzyl-1,3,5-triazacyclohexane (Bz3TAC) to give the cationic complex [(Bz3TAC)Zn(Et)](PF6). The crystal and molecular structure of the compound has been determined by X-ray diffraction. This structure agrees with the structure previously predicted by NOESY spectroscopy for the related compounds [(FBz3TAC)Zn(Et)](BF4)(FBz ue5fb p-fluorobenzyl) and [{(s-PhMeCH)3TAC}Zn(Et)]([BF4). The differences can be explained by close PF6−ue5f8Zn contact in the solid state.

Metallorganische verbindungen der lanthanoide: LXXXV. Synthese und strukturaufklärung neuer cyclooctatetraenyl-cyclopentadienyl-sandwich-komplexe der seltenen erden

Abstract The mixed sandwich complexes [(C 8 H 8 )Ln(C 5 Me 4 Et)(THF) x ] (Ln = Y 1 , La 2 , Nd 3 , Sm 4 , Gd 5 , Tm 6 , Lu 7 ), [(C 8 H 8 )Ln{C 5 H 2 (SiMe 3 ) 3 }(THF) x (Ln = Pr 8 , Dy 9 ) and [(C 8 H 8 )Pr(C 5 Ph 5 )] ( 10 ), have been prepared by the metathetic reaction of [(C 8 H 8 )Ln(μ-Cl)-(THF) n ] 2 with NaC 5 Me 4 Et, LiC 5 H 2 (SiMe 3 ) 3 and NaC 5 Ph 5 in THF. The 1:2 reaction of 7 with acetylacetone results in displacement of the (C 8 H 8 )-ligand to generate the new complex [(C 5 Me 4 Et)Ln(acac) 2 ] (acac = [CH 3 C(O)CHC(O)CH 3 ] − ) ( 11 ). The molecular structures of 7 (monoclinic space group P 2 1 / c with a = 990.4(5) pm, b = 1228.2(5) pm, c = 2757.5(16) pm, β = 93.92(4)°, V = 3346(3)·10 −30 m 3 and Z = 8) and 11 (triclinic space group P 1 with a = 957.3(3) pm, b = 1064.5(2) pm, c = 1068.3(2) pm, α = 94.19(12)°, β = 96.37(17)°, γ = 96.71(16)°, V = 1070.3(4)·10 −30 m 3 and Z = 2) have been determined by X-ray diffraction.