Trimeth­yl(triphenyl­meth­oxy)silane

In the title mol­ecule, C₂₂H₂₄OSi, the Si—O—C angle is 139.79 (11)°, the O—C—C angles of the triphenyl­meth­oxy group are in the range 106.13 (13)–109.22 (14)° and the O—Si—C angles of the trimethyl­sil­yloxy group are in the range 103.08 (10)–113.53 (10)°. In the crystal, face-to-face π–π interactions are observed between the phenyl rings [centroid separation = 4.194 (1) Å, interplanar spacing = 3.474 Å and centroid shift = 2.35 Å]. The three phenyl groups of the triphenyl­methyl substituent are mutually nearly perpendicular, with dihedral angles in the range 80.49 (8)–81.53 (8)°. There are only weak inter­molecular van der Waals inter­actions in the crystal.

2-Methylxanthen-9-one

In the title compound, C₁₄H₁₀O₂, the tricycle is not planar, being bent with a dihedral angle of 4.7 (1)° between the two benzene rings. In the crystal, π–π inter­actions between the six-membered rings of neighbouring mol­ecules [centroid–centroid distances = 3.580 (3) and 3.605 (3) Å] form stacks propagating along [101].

3-(4-Chloro­anilino)-5,5-dimethyl­cyclo­hex-2-en-1-one

The asymmetric unit of the title compound, C₁₄H₁₆ClNO, contains two independent mol­ecules, both with the cyclo­hexene ring in a sofa conformation. In the crystal, N—H...O hydrogen bonds link the mol­ecules related by translation along the a axis into two crystallographically independent chains. Weak C—H...π inter­actions are also observed.

(E)-4-(4-Meth­oxy­phen­yl)but-3-en-2-one

In the title compound, C₁₁H₁₂O₂, the dihedral angle between the benzene ring and the but-3-en-2-one group is 4.04 (5)°. The crystal packing features chains, parallel to [-101], composed of dimers connected by weak C—H...O inter­actions..

Ethyl 2-[4-(2-chloro­benzo­yl)-2,6-di­methyl­phen­oxy]ethano­ate

The asymmetric unit of the title compound, C₁₉H₁₉ClO₄, contains two independent mol­ecules. The dihedral angles between the benzene rings are 63.41 (8) and 61.41 (9)°. Adjacent mol­ecules of different types are inter­connected in pairs through π–π inter­actions between their central benzene rings [centroid–centroid separation = 3.801 (2) Å, inter­planar spacing = 3.605 (2) Å, centroid shift = 1.204 (2) Å]. Finally, C—H...O hydrogen bonds link these dimers into bilayers parallel to (100).

2-Amino-7,7-dimethyl-5-oxo-4-(p-tol­yl)-5,6,7,8-tetra­hydro-4H-chromene-3-carbonitrile

In the title mol­ecule, C₁₉H₂₀N₂O₂, the cyclo­hexene ring adopts a sofa conformation, while the pyran ring adopts a flattened boat conformation. In the crystal, mol­ecules are linked by N—H...N and N—H...O hydrogen bonds, forming a two-dimensional network parallel to (010).