Homoleptic dirhodium tetraoctanoate and its pyridine adduct: synthesis and crystal structures

Abstract

Dirhodium tetraoctanoate (1), without any exogenous axial ligands, has been obtained in crystalline form by slow evaporation from ethanol. The molecules are linked by axially ligating each other to form infinite chains, which is similar to the only other two structurally characterized rhodium(II) carboxylates, Rh 2 (O 2 CCF 3 ) 4 and Rh 2 (O 2 CC 3 H 7 ) 4 , which also lack exogenous axial ligands. The infinite chains of 1 are cleaved by strong donor solvents such as pyridine to produce the corresponding pyridine adduct (2). Both the complexes were characterized by elemental analysis, MS, IR and NMR spectra.

Synthesis, crystal structures and catalytic activity of tetrakis(acetato)dirhodium(II) complexes with axial picoline ligands

“…It is noteworthy that no complexes show M + peaks, presumably due to the low stability of their axial ligands under electron spray ionization, which are Symmetry code: A: Àx + 1, Ày + 1, Àz + 2. Symmetry code: A: Àx, Ày, Àz + 2. consistent with our previous observation for bis(pyridine) adducts of dirhodium tetraoctanoate [24]. The UV-Vis spectra of 1-3 in three different solvents are showed in Fig.…”

Crystal structure of tetrakis(acetato)bis(4-pyridinemethanol)dirhodium, Rh2(C2H3O2)4(C6H7NO)2

“…However, compared to Rh 2 (O 2 CCH 3 ) 4 (py) 2 ,n ot only the Rh-Rh bond lengths in the title complex slightly increase from 2.3963(2) to 2.4030 (7) Å,but the Rh-Ndistances also increase by 0.016 Å,which is opposite to that expected for trans-effect influences in respect to the Rh-Rh bond. The pyridyl rings in the title complex are parallel to each other with adistance of 3.615 Å between the nearest neighbors, and the distance between their centroids is 4.103 Å,which indicates p-p packing interactions [9]. The crystal packing of the title complex is further stabilized by hydrogen bonds formed between Oatoms of 4-pyridinemethanol and that of the acetates with d(O···O) of 2.881(3) Å.…”

Ring-Strain-Driven Catalytic Carbene Formation–Cyclopropanation–Aza-Cope Rearrangement Cascade: A Facile Entry to Fused Dihydroazepines from 1,3-Dienyltriazoles

“…Commercially available reagents were used without further purification. TsN 3 , 7 TcCu, 8 Rh 2 (Ooct) 4 , 9 Rh 2 (S-PTTL) 4 •2EtOAc, 10 Rh 2 (esp) 2 11 were prepared according to reported methods. 1 H and 13 C NMR spectra were recorded in deuterated solvents on Bruker AV-400/AV-500 spectrometers at r.t. High-resolution mass spectra were acquired on an Agilent 6230 spectrometer and were obtained by peak matching with a Finnigan MAT 8430 spectrometer.…”