-When 1-hexene was adsorbed by Cr3+-montmorillonite at room temperature, all evidence of C=C(str) vibrations was lost. Protonation of the alkene occurred, and the secondary carbocation formed was bound at a site on the primary coordination sphere of the interlayer cation. Some of the hydrogen atoms of these primary-sphere water molecules were involved in strong hydrogen bonds to the silicate sh...

In the title compound, C(15)H(12)OS, the cyclo-hexene ring has a twisted boat conformation with the C atom between the ketone and methyl-ene atom and this methyl-ene C atom lying 0.280 (3) and 0.760 (3) Å, respectively, from the plane through the remaining four atoms (r.m.s. deviation = 0.004 Å). The dihedral angle between the benzene and thio-phene rings [21.64 (9)°] indicates an overall twist...

In the title 1,2,4-triazine derivative, C(17)H(19)N(3)O(3), the heterocyclic ring is planar (r.m.s. deviation = 0.040 Å) and effectively coplanar with the adjacent phenyl ring [dihedral angle = 4.5 (2)°] but almost perpendicular to the (cyclo-hex-3-en-1-ylmeth-oxy)methyl residue [N-N-C-O torsion angle = 71.6 (5)°], so that the mol-ecule has an 'L' shape. Supra-molecular chains along [001] are f...

In the title compound, C23H20BrNO2S, disorder was modeled for the outer two C atoms of the cyclo-hexene ring over two sets of sites with an occupancy ratio of 0.580 (11):0.420 (11). Both rings have a half-chair conformation. The dihedral angles between the mean plane of the thio-phene ring and the benzene and phenyl rings are 9.2 (2) and 66.1 (2)°, respectively. The benzene and phenyl rings are...

The title compound, [Sn(CH(3))(3)(C(7)H(9)O(2))](n), forms an extended zigzag chain structure propagating parallel to [010]. The Sn atom is in a slightly distorted trigonal-bipyramidal coordination environment with two carboxyl-ate O atoms in the axial and the three methyl groups in equatorial sites. The cyclo-hexene ring has a distorted half-boat conformation. There is an intra-molecular C-H⋯O...

The title compound, C(23)H(23)NO, is the product of a tandem transformation of the double Mannich base bis-(1-oxo-1,2,3,4-tertrahydro-2-naphtho-ylmeth-yl)amine hydro-chloride in HBr solution upon heating. The tetra-hydro-pyridine ring has a non-symmetrical half-chair conformation, whereas the cyclo-hexa-diene and cyclo-hexene rings adopt non-symmetrical half-boat conformations. The dihedral ang...

The title compound {systematic name: 5,6,10-trihydr-oxy-7-iso-propyl-1,1,4a-trimethyl-2,3,4,4a-tetra-hydro-phenanthren-9(1H)-one}, C(20)H(26)O(4), is a diterpenoid which was isolated from the roots of Premna obtusifolia. The mol-ecule has three fused six-membered rings; the cyclo-hexane ring is in a twisted-boat conformation and the cyclo-hexene ring adopts a sofa form. Intra-molecular O-H⋯O hy...

In the title compound, C(25)H(36)N(2)O(2)S, the cyclo-hexane and morpholine rings adopt chair conformations. The cyclo-hexene and cyclo-hexane rings form a trans ring junction with the two methyl groups in axial positions. The N-H and C=O bonds in the urea group are anti to each other. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.

The title compound, C(22)H(28)O, was isolated from the aerial part of Inula viscosa- (L) Aiton [or Dittrichia viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation being substituted at position 2 by a 3-(4-methyl-phen-yl)prop-2-enoyl group. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules ...