Crystal structure of 1,2,3,4,5-pentamethyl-1,3-cyclopentadiene, C₁₀H₁₆

Abstract

CCDC no.: 1541210The asymmetric unit of the title crystal structure is shown in the figure. Tables 1 and 2 contain details of the measurement method and a list of the atoms including atomic coordinates and displacement parameters. Source of materialsZn 2 (Cp*) 2 (Cp* = pentamethylcyclopentadienyl) was prepared as described in literature [5]. 40 mg Zn 2 (Cp*) 2 were given into a dry Schlenk vessel and ca. 2 ml NH 3 (Westfalen AG, 99.999%, stored over elemental Na) were condensed on this. The formerly colourless complex got spontaneously black. The vessel was stored at −70°C for five months, after this time colourless crystals of the title compound in a yield of about 20 mol% with respect to Zn 2 (Cp*) 2 were found. An

Dominant changes in centre Fe atom of decamethyl-ferrocene from ferrocene in methylation

“…It is then possible that not all C-C bonds in the *Cp ring are equivalent. The C-C and C=C bonds exhibiting sp 3 and sp 2 hybridizations are claimed by a recent crystal structure determination (*CpH) [39]. In low-temperature phase (296 K), the crystal structure of *Fc was ordered with the staggered conformation, using single-crystal X-ray diffraction [24] which was confirmed by single-crystal neutron diffraction techniques (100 K) by Sanjuan-Szklarz et al [40].…”

How Many Molecules Can Fit in a Zeolite Pore? Implications for the Hydrocarbon Pool Mechanism of the Methanol-to-Hydrocarbons Process

“…We used three different methods to determine the molecular volume (see Section 4 as this is not a well-defined parameter. It can be seen that the Molinspiration [12] values (which are calculated as a sum of group contributions) are consistently smaller than those based on experimental values (crystal structure [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] and density [33]). However, while the absolute values differ between the methods, in all three cases the trends are similar and they match chemical intuition, e.g., phenanthrene is larger than toluene.…”

“…This is seen as a sum of group contributions. The data in column 3 of Table 1 (labelled 'Structure') was generated from the crystal structures [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32], which were obtained from the Cambridge Structural Database (CSD) [62]. We define the molecular volume as the unit cell volume divided by the number of molecules in the unit cell.…”

Crystal structure of (1,4,7,10,13,16-hexaoxacyclooctadecane-κ6 O 6) 1,2,3,4,5-pentamethyl-cyclopenta-2,4-dien-1-yl(potassium, rubidium) — ammonia (1/2), [K0.3Rb0.7(18-crown-6)]Cp*⋅2 NH3, C22H45K0.3N2O6Rb0.7

“…Rb is bound to the Cp* ligand via five short Rb-C bonds between 3.055(4) Å and 3.199(3) Å very similar to those observed for the η 5 coordinations in [Rb(18crown-6)]Cp* [12] and [Rb(18-crown-6)]Cp* × thf [14]. All C atoms of the Cp* ligand are in plane and the cyclopentadienyl ring is an almost regular pentagon (C-C bond lengths between 1.394(5) Å and 1.423(5) Å, C-C-C angles between 106.9(3)°and 108.9(3)°), clearly different from the shape of the neutral Cp*-H molecule [15], suggesting that the negative charge is located at Cp*. Confirming this and additionally excluding the presence of possible amide anions instead, for each of the ammonia molecules three H atoms could have been located from the Fourier map.…”