Bildung Siliciumorganischer Verbindungen. 103. Bildung und Struktur von cis- und trans-2,4-Dichloro-2,4-bis(trimethyl-silyl)-1,1,3,3-tetramethyl-1,3-disilacyclobutan

Formation of Organosilicon Compounds. 103. Formation and Structure of cis and trans 2,4-Dichloro-2,4-bis(trimethylsilyl)-1,1,3,3-tetramethyl-1,3-disilacyclobutane The reaction of Me₃Si? CCl₂? SiMe₂Cl with LiBu in THF yields 1,1,3,3-Tetramethyl-2,4-bis(trimethylsilyl) 1,3-disilabicyclo[1.1.0]butane. The product of the first reaction stage is Me₃Si? CCl(Li)-SiMe₂Cl. The 1,3-Disilacyclobutane 2 and 3 were isolated, when Me₃Si? CCl₂? SiMe₂Cl was treated with LiBu in Et₂O. This way the proof is given that 2 and 3 are intermediates of the formation of product 1 . The further products are 4 and 5 (CCl in 2 and 3 substituted by CH) and Me₃Si? CH₂? C(SiMeCl)₂SiMe₃. 2 crystallizes orthorhombically in the space group Fdd 2 (no. 43) with a = 2149.1 pm, b = 2229.2 pm, c = 1763.6 pm and Z = 16 molecules per cell. The central ring of disilacyclobutane is slightly folded (17.9°). The configuration of the C-Atoms in this four membered ring gets closer to a sp² configuration built up by three Si? C bonds. The Cl-atoms approximately have orthogonal positions to these CSi₃ arrangements. The extension of the C? Cl bonds (184.6 pm) and the mutual approximations of the Cl-atoms in the cis-position indicate a high reactivity of the molecule.     

Bildung siliciumorganischer Verbindungen. 112. Über den Einfluß der Reaktionsbedingungen auf die Umsetzung von (Cl3Si)2CCl2 mit Silicium. Die Struktur von 2,2,3,3,5,5,6,6-Octachlor-1,4-bis(trichlorsilyl)-2,3,5,6-tetrasilabicyclo[2.1.1]hexan und 1,1,3,4,6,6-Hexakis(trichlorsilyl)hexatetraen

Formation of Organosilicon Compounds. 112. The Influence of Reaction Conditions on the Reaction of (Cl₃Si)₂CCl₂ with Silicon. The Structures of 2,2,3,3,5,5,6,6-Octachloro-1,4-bis(trichlorosilyl)-2,3,5,6-tetrasilabicyclo[2.1.1]-hexane and 1,1,3,4,6,6-Hexakis(trichlorosilyl)hexatetraene While reactions of (Cl₃Si)₂CCl₂ 1 with Si(Cu) in a fluid bed at 320°C exclusively yield products by silylation of the CCl₂ group in 1 does the reaction in a stirred bed preferrably give rize to chlorosilanes containing C? C double and triple bonds. Compounds 5, 6, 7, 8 and 9 in Tab. 1 belong to the first group, whereas 3 and 4 belong to the second one. The reaction of 1 with elemental copper under dehalogenation at carbon produces 3, 4 and 11 . In the reaction of 1 with CaSi₂ no additional Si? C bonds are formed, exclusively chlorosilanes with multiple C? C bonds as 3, 4 and 10 were found besides of SiCl₄. The bicyclo[2.1.1]hexane 6 (Tab. 1) crystallizes monoclinically in the space group C2/c (no. 15) with a = 1557.8, b = 857.4, c = 1727.3 pm, β = 104.34° und Z = 4 molecules per unit cell; the hexatetraene 10 (Tab. 1) crystallizes monoclinically in the space group C2/m (no. 12) with a = 1189.6, b = 1433.8, c = 983.5 pm, β = 98.75° pm, and Z = 2 molecules per unit cell. The skeleton of 6 is a system of high bond stress with 2-C₂ symmetry. The strongly folded (138.8°) four-membered ring (sum of angles = 344.2°) and the presence of both a Si? Si bond length of 238.2 pm and a Si? Si non-bonding distance of 255.1 pm are remarkable aspects of this feature. The mean bond lengths in the bicyclic compound were found to be d(Si? C) = 190.9 pm and d(Si? C) = 185.1 pm for exo- and endocyclic bonds, respectively. The skeleton of 10 is of the symmetry 2/m-C_2h. The six-membered chain is plane. The central C? C single bond length and the mean distance of the cumulated double bonds are 148.6 pm and 130.5 pm, respectively.     

Bildung siliciumorganischer Verbindungen. 94. Die Kristallstruktur des Hexaphenyltrisilacyclohexans Si3C39H36

Formation of Organosilicon Compounds. 94. Crystal Structure of Hexaphenyltrisilacyclohexane Si₃C₃₉H₃₆ 1.1.3.3.5.5-Hexaphenyl-1.3.5-trisilacyclohexane crystallizes monoclinically in the space group P2₁/n (No. 14) with a = 1718.3 pm, b = 1769.2 pm, c = 1091.4 pm, β = 90.72° and Z = 4 molecules per unit cell. The trisilacyclohexane sceleton is present in a flattened twist boat conformation with mean bond angles of 110.0° at the Si atoms and 117.9° at the C atoms, respectively. The mean bond lengths are d(Si? C) = 187.1 pm in the six membered ring and 187.9 pm to the substituents.     

Iridium‐Catalyzed Silylation of Five‐Membered Heteroarenes: High Sterically Derived Selectivity from a Pyridyl‐Imidazoline Ligand

The steric effects of substituents on five‐membered rings are less pronounced than those on six‐membered rings because of the difference in bond angles. Thus, the regioselectivities of reactions of five‐membered heteroarenes that occur with selectivities dictated by steric effects, such as the borylation of C?H bonds, have been poor in many cases. We report that the silylation of five‐membered‐ring heteroarenes occurs with high sterically derived regioselectivity when catalyzed by the combination of [Ir(cod)(OMe)]₂ (cod=1,5‐cyclooctadiene) and a phenanthroline ligand or a new pyridyl‐imidazoline ligand that further increases the regioselectivity. The silylation reactions with these catalysts produce high yields of heteroarylsilanes from functionalization at the most sterically accessible C?H bonds of these rings under conditions that the borylation of C?H bonds with previously reported catalysts formed mixtures of products or products that are unstable. The heteroarylsilane products undergo cross‐coupling reactions and substitution reactions with ipso selectivity to generate heteroarenes that bear halogen, aryl, and perfluoroalkyl substituents.     

(3R,4aS,5R)‐3‐Hydro­xy‐5‐isopropenyl‐3,8‐di­methyl‐4,4a,5,6‐tetra­hydro‐2(3H)‐naphthalenone

In the crystal structure of C₁₅H₂₀O₂, mol­ecules are associated by intermolecular hydrogen bonds between the hydroxy function and a keto group [O?O 2.770 (2) Å], forming chains along the [100] direction in the crystal. Both six‐membered rings in the decalin unit adopt envelope conformations; one section of the mol­ecule, encompassing the extended conjugation of a C=C double bond with an enone functionality [C=C—C=O = 175.6 (2)° and C=C—C=C = 176.6 (2)°], is flat, whilst the rest of the mol­ecule is folded relative to the constrained part. The stereochemistry was determined from the R‐(–)‐carvone starting material.     

Cycloadditionsreaktionen von Trifluormethylisocyanid an Diphosphene. Synthese und Struktur des neuartigen 2-Phosphiniden-1, 3-azaphospholidins

Cycloaddition Reactions of Trifluoromethyl Isocyanide with Diphosphenes. Synthesis and Structure of the new 2-Phosphinidene-1,3-azaphospholidine Derivative [2 + 1] Cycloaddition reactions of trifluoromethyl isocyanide 1 and methylisocyanide 2 with the diphosphene R? P?P? R 3a ( a R ? C[Si(CH₃)₃]₃) yield the three membered heterocyclic diphosphirane imines 4 and 5 , respectively. Whereas the trifluoromethyl substituted compound 4 is thermally very stable, the methylsubstitued derivative 5 slowly looses methyl isocyanide reforming the diphosphene 3a . In the reaction of 1 with R? P?P? R 3b [ b R = 2,4,6-(t-Bu)₃C₆H₂] no evidence for the formation of a three membered ring compound could be obtained. The five membered heterocycle 3-(2,4,6-Tri-t-butylphenyl)-2-[2,4,6-tri-t-butylphenyl)-phosphinidene]-1-trifluoromethyl-4, 5-bis(trifluoromethylimin)-1,3-azaphospholidine 6 was isolated as the only product together with unreacted 3b . The structure of 6 , triclinic, P1 , a = 1081.1(8), b = 1463.1(11), c = 1643.6(5)pm, α = 64.01(6), β = 81.22(4), γ = 74.04(5)°, Z = 2, R = 0.080, R_w = 0.085, has been elucidated by X-ray diffraction.     

Building up Strain in One Step: Synthesis of an Edge‐Fused Double Silacyclobutene from an Extensively Trichlorosilylated Butadiene Dianion

The exhaustive trichlorosilylation of hexachloro‐1,3‐butadiene was achieved in one step by using a mixture of Si₂Cl₆ and [nBu₄N]Cl (7:2 equiv) as the silylation reagent. The corresponding butadiene dianion salt [nBu₄N]₂[ 1 ] was isolated in 36 % yield after recrystallization. The negative charges of [ 1 ]^2? are mainly delocalized across its two carbanionic (Cl₃Si)₂C termini (α‐effect of silicon) such that the central bond possesses largely C=C double‐bond character. Upon treatment with 4 equiv of HCl, [ 1 ]^2? is converted into neutral 1,2,3,4‐tetrakis(trichlorosilyl)but‐2‐ene, 3 . The Cl^? acceptor AlCl₃, induces a twofold ring‐closure reaction of [ 1 ]^2? to form a six‐membered bicycle 4 in which two silacyclobutene rings are fused along a shared C=C double bond (84 %). Compound 4 , which was structurally characterized by X‐ray crystallography, undergoes partial ring opening to a monocyclic silacyclobutene 2 in the presence of HCl, but is thermally stable up to at least 180 °C.     

Beiträge zur Strukturchemie phosphorhaltiger Ketten und Ringe. 11. Die Kristall- und Molekülstrukturen der beiden Konfigurationisomeren des Tetraphospha-silaspiro[2.2]pentans (PBut)2Si(PBut)2

Structural Chemistry of Phosphorus Containing Chains and Rings. 11. Crystal and Molecular Structures of the Two Stereoisomers of Tetraphospha-silaspiro[2.2]pentane (PBu^t)₂Si(PBu^t)₂ The spirocyclic compound 1,2,4,5-tetra-tert-butyl-1,2,4,5-tetraphospha-3-silaspiro[2.2]pentane exists in tow diastereomers of point symmetry 4 and 2. The isomer with symmetry 4 even in the solid crystallizes tetragonally in I4₁/a with a = 1247.0, c = 1505.5 pm and Z = 4. The isomer of fairly exact symmetry 2 crystallizes triclinically in P1 with a = 612.8, b = 996.3, c = 1017.2 pm, α = 75.63, β = 72.38, γ = 88.71° and Z = 1. In this disordered structure the surroundings of Si is slightly distorted due to the influence of the substituents. The (average) bond lengths are (4 , 2): d(Si? P) = 220.09(9), 221.5(5); d(P? P) = 225.5(2), 224.2(5); d(P? C) = 189.4(3), 190(2); d(C? C) = 151.4(4), 152(3) pm. The geometry of the substituents in both isomers is quite normal.     

Reaction of N‐Heterocyclic Silylenes with Thioketone: Formation of Silicon–Sulfur Three (Si‐C‐S)‐ and Five (Si‐C‐C‐C‐S)‐Membered Ring Systems

Three‐ and five‐membered rings that bear the (Si‐C‐S ) and (Si‐C‐C‐C‐S ) unit have been synthesized by the reactions of L SiCl ( 1 ; L =PhC(NtBu)₂) and L′ Si ( 2 ; L′ =CH{(C?CH₂)(CMe)(2,6‐iPr₂C₆H₃N)₂}) with the thioketone 4,4′‐bis(dimethylamino)thiobenzophenone. Treatment of 4,4′‐bis(dimethylamino)thiobenzophenone with L SiCl at room temperature furnished the [1+2]‐cycloaddition product silathiacyclopropane 3 . However, reaction of 4,4′‐bis(dimethylamino)thiobenzophenone with L′ Si at low temperature afforded a [1+4]‐cycloaddition to yield the five‐membered ring product 4 . Compounds 3 and 4 were characterized by NMR spectroscopy, EIMS, and elemental analysis. The molecular structures of 3 and 4 were unambiguously established by single‐crystal X‐ray structural analysis. The room‐temperature reaction of 4,4′‐bis(dimethylamino)thiobenzophenone with L′ Si resulted in products 4 and 5 , in which 4 is the dearomatized product and 5 is formed under the 1,3‐migration of a hydrogen atom from the aromatic phenyl ring to the carbon atom of the C? S unit. Furthermore, the optimized structures of probable products were investigated by using DFT calculations.     

Beiträge zur Strukturchemie phosphorhaltiger Ketten und Ringe. 16. Die Molekül- und Kristallstruktur des Triisopropyl-undecaphosphans P11(i-Pr)3

Structural Chemistry of Phosphorus Containing Chains and Rings. 16. Molecular and Crystal Structure of the Triisopropylundecaphosphane P₁₁(i-Pr)₃ The compound 4,7,11-triisopropyl-pentacyclo[6.3.0.0^2.6.0^3.10.0^5.9]undecaphosphane, C₉H₂₁P₁₁, crystallizes triclinically in the space group P1 with a = 1 045.3 pm, b = 1 057.2 pm, c = 1 075,0 pm, α = 101.00°, β = 98.89°, γ = 112.27° and Z = 2. The main structural feature is a phosphorus skeleton with approximate symmetry D₃ composed of six five-membered rings which are asymmetrically substituted by the isopropyl groups. The (average) bond lengths are d(P? P) = 221.6 pm, d(P? C) = 187.5 pm, d(C? C) = 151.4 pm, d(C? H) = 108 pm with 217.6 ≤ d(P? P) ≤ 226.4 pm. The geometry of the substituents is quite normal.     

Synthese und Kristallstruktur von [Se3N2Cl]+ GaCl4−

Synthesis and Crystal Structure of [Se₃N₂Cl]⁺GaCl₄^? [Se₃N₂Cl]⁺GaCl₄^? has been prepared by the reduction of [Se₂NCl₂]⁺GaC1₄^? with SbPh₃ in CH₂Cl₂ solution, forming red crystals, which were characterized by an X-ray structure determination. Space group P2₁/n, Z = 4, 1640 observed unique reflections, R = 0.050. Lattice dimensions at ? 80 °C: a = 929.4(1), b= 1078.8(1), c = 1135.7(1) pm, β = 92.026(9)°. The cations from nearly planar Se₃N₂ five membered rings with Se? N bond lengths from 170 to 176pm and a Se? Se bond of 242.2 pm. One of the selenium atoms is bonded to the chlorine atom.     

Molekül- und Kristallstruktur des 1,4-Bis[tris(tetrahydrofuran)lithium]-octaphenyltetrasilans

Molecular and Crystal Structure of 1,4-Bis[tris(tetrahydrofuran)lithium]-octaphenyltetrasilane 1,4-Dilithium-octaphenyltetrasilane prepared from octaphenyl-cyclo-tetrasilane and lithium in tetrahydrofuran (THF) [4], can be isolated from tetrahydrofuran/n-pentane as an adduct with six molecules of tetrahydrofuran per formula unit. The orange-red compound crystallizes in the triclinic space group P1 {a = 1159.6(3); b = 1268.4(2); c = 1367.8(3) pm; α = 92,23(2)° β = 113.79(2)° γ = 111.62(2)° at ?5 ± 3°C; Z = 1}. An x-ray structure determination (R_w = 0.046) shows the existence of a centrosymmetric molecule with an extended planar Li? Si₄? Li unit; either lithium atom is bound to silicon and to the oxygen atoms of three molecules of tetrahydrofuran. Characteristic bond lengths and angles are: Li? Si 271; Si? Si 241 and 243; Si? C 190 to 192 pm; Li? Si? Si 126°; Si? Si? Si 127°. ²⁹Si and ⁷Li n.m.r. measurements at low temperatures indicate the presence of three different adducts.     

Beiträge zur Strukturchemie phosphorhaltiger Ketten und Ringe. 1. Die KristallStruktur des Diphosphasilirans (t-BuP)2SiPh2

Structural Chemistry of Phosphorus-containing Chains and Rings. 1. Crystal Structure of the Diphosphasilirane (t-BuP)₂SiPh₂ The three-membered P₂Si-heterocycle 1, 2-di-tert-butyl-3, 3-diphenyl-1, 2, 3-diphosphasilirane (t-BuP)₂SiPh₂ crystallizes monoclinic in the space group P2₁ with a = 1041.2 pm, b = 882.3 pm, c = 1158.1 pm, β = 91.33° and Z = 2 formula units. A special structural feature is the regular triangle built up by two P and one Si. Therefore the endocyclic bond angle at Si is as low as 60°. The average bond lengths are P? P = 222.6 pm, P? Si = 222.5 pm, P? C = 190.8 pm, Si? C = 186.6 pm, (C? C )ph = 139.0 pm, ( C? C )_t-Bu = 151.7 pm. The geometry of the substituents phenyl and tert-butyl is quite normal, the last ones are slightly disordered.     

Chelatkomplexe von Rheniumtetrachlorid. Die Kristallstrukturen von ReCl4(DME) und ReCl4(DPPE) · Tolan

Chelate Complexes of Rhenium Tetrachloride. The Crystal Structures of ReCl₄(DME) and ReCl₄(DPPE) · Tolan Bright green crystals of ReCl₄(DME) have been prepared by the reaction of rhenium pentachloride with dimethoxyethane (DME) in dichloromethane. ReCl₄(DPPE) · tolan was obtained in form of red crystals by the reaction of the alkyne complex [ReCl₄(Ph? C?C? Ph)(POCl₃)] with bis(diphenylphosphino)ethane (DPPE) in dichloromethane. The complexes were characterized by X-ray structure determinations. ReCl₄(DME): Space group I4 2d, Z = 8, 829 observed unique reflexions, R = 0.022. Lattice dimensions at 19.5°C: a = b = 960.60(6), c = 2337.2(6) pm. The complex forms monomeric molecules with DME as chelating ligand; the Re? O bond lengths are 213.1 pm. The chlorine atoms, arranged in trans position to the chelating ligand, have slightly shorter Re? Cl bonds than the chlorine atoms in cis position (232,1 pm). ReCl₄(DPPE) · tolan: Space group P2₁/n, Z = 4,4313 observed unique reflexions, R = 0.040. Lattice dimensions at ?80°C: a = 1095.7(1), b = 1764.2(2), c = 1898.0(2) pm, β = 99.229(8)°. The compound consists in form of monomeric molecules [ReCl₄(DPPE)] and diphenylacetylene molecules, which are incorporated in the lattice. The two phenyl rings of the tolan molecules are twisted towards each other along the C? C axis with a dihedral angle of 21°. The DPPE molecules are bonded to the rhenium atom in a chelating fashion with medium Re? P lengths of 250.4 pm. The chlorine atoms, arranged in trans position to this ligand, with Re? Cl bond lengths of 234.5 pm are slightly longer than the Re? Cl bonds in cis position with 232.3 pm.     

Cyclische Diazastannylene. XXVIII. Anorganische Polycyclen aus der Reaktion eines Bis(amino)-stannylens bzw. eines Iminostannylens mit SnCl2, SnBr2 und tert-Butoxizinn(II)-chlorid bzw. -bromid

Cyclic Diazastannylenes. XXVIII. Inorganic Polycyclic Compounds from the Reaction of Bis(amino)stannylene or Iminostannylene with SnCl₂, SnBr₂, and tert-Butoxitin(II) Chloride or Bromide The cyclic bis(amino)stannylene 1 may react with tert-butoxitin(II) chloride or bromide yielding a Lewis acid-base adduct 4 resp. 5 , in which the two molecules are held together via N→Sn (233.8(3) pm) and O→Sn (215.1(2) pm) bonds. The resulting adduct 4 contains therefore two four membered rings sharing one common edge as found by X-ray structure determination. If 1 is allowed to react with SnCl₂ or SnBr₂, the salts Me₂Si(N^tBu)₂Sn₂Br⁺Sn₂Br₅^? ( 7 ) are formed. Structure analysis reveals the cations in 6 and 7 to be very similar: SnCl⁺ and SnBr⁺ are coordinated by the “trihapto ligand” 1 in a way resulting a polycyclic SiN₂Sn₂X-arrangement. To a central Sn₂N₂ tetrahedron Si and halogen X are added occupying and bridging two opposite edges (mean values: N? Sn = 232(5) ( 6 ), N? Sn = 230(2) ( 7 ), Sn? C1 = 265(1), Sn? Br = 275(1) pm). The reaction intermediate (SnN^tBu)₂ adds to SnCl₂ to form the crystalline polymer ( ^tBuN)₂Sn₃C1₂ (8) . X-ray structure determination reveals the solid to be built up by one-dimensional chains of polycyclic Sn₃(N^tBu)₂C1₃ sharing two chlorine atoms with neighbouring units. The unit Sn₃(N^tBu)₂C1₃ can be visualized as an equilateral triangle of chlorine atoms, on which a smaller triangle of tin atoms is superimposed; the corners of the smaller triangle being located in the middle of the larger triangle's edges. The tin atoms are bipyramidally coordinated by two N? ^tBu-groups thus forming a nearly perfect Sn₃N_2s trigonal bipyramide (Sn? N = 222.7(3) pm). Two chlorine atoms of the triangle are connected to neighbouring units, the chlorine atoms thus attain an unusual nearly square-planar coordination sphere (Sn? Cl(mean) = 308(5) pm). The tertbutyl groups at the nitrogen atoms “screen” the inorganic part of the structure leading to a layer structure.     

Zur Chemie und Strukturchemie der Phosphide und Polyphosphide. 15. Gadoliniumpentaphosphid GdP5

Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 15. Gadoliniumpentaphosphide GdP₅ GdP₅ is formed by heating (550–800°C) of Gadolinium powder and red phosphorus with small amounts of iodine. GdP₅ crystallizes monoclinic in the space group P2₁/m with a = 4.928, b = 9.446, c = 5.370 Å, β = 102.58° and Z = 2 formula units. GdP₅ is isotypic to NdP₅. The bond lengths vary between 2.161 and 2.211 Å for the P? P bonds and 2.947 and 3.014 Å for the Gd? P bonds. The 2-dimensional network of P atoms is related to connected six membered rings (boat conformation) with specific defects. GdP, is paramagnetic with μ = 7.83 B.M.     

Acyl- und Alkylidenphosphane. XXIII [1]. Synthese und Struktur der [Bis(trimethylsilylsulfano)methyliden]phosphane

Acyl- and Alkylidenephosphines. XXIII. Synthesis and Structure of [Bis(trimethylsilylsulfano)methylidene]phosphines Analogous to the phenyl derivative 1a [2] tert-butyl- 1b , mesityl- 1c and methylbis-(trimethylsilyl)phosphine 1 d react with carbon disulfide to give the corresponding [bis(trimethylsilylsulfano)methylidene]phosphines 4 . Only in case of the mesitylphosphine 1 c the intermediate compounds 2 and 3 could be detected by n.m.r. spectroscopic methods; thermally unstable [bis(trimethylsilylsulfano)methylidene]methylphosphine 4 d dimerizes rapidly [1]. [Bis(trimethylsilylsulfano)methylidene]phenylphosphine 4 a crystallizes in the monoclinic centrosymmetric space group P2₁/c with following dimensions of the unit cell determined at ?95 ± 3°C: a = 1386.4(8); b = 1036.0(7); c = 1281.7(8) pm; ß = 101.23(4)°; Z = 4. An X-ray structure determination (R = 0.032) proves the constitution of this compound as already derived from its nmr spectra. Characteristic bond lengths and angles are: P?C 170; P? C(phenyl) 183; C? S 176; S? Si 219 pm; C? P?C 107; P?C? S 124 and 120; S? C? S 116 and C? S? Si 111°.     

Beiträge zur Chemie der Silicium-Schwefel-Verbindungen. XXXIII. Die Struktur des Bis(triphenylsilyl)sulfids

Contributions to the Chemistry of Silicon Sulphur Compounds. XXXIII. Structure of Bis (triphenylsilyl)sulphide The condensation of triphenylsilanethiol yielded bis(triphenylsilyl)sulphide ( 1 ). The compound is remarkable resistent to hydrolysis. 1 crystallizes monoclinically [P2₁/n (No. 14): a = 1707.8 pm; b = 1454.6 pm; c = 1225.0 pm; β = 97.27°; Z = 4; 4470 h k l; R = 0.053]. The molecule is bent with a bond angle Si? S? Si = 112.0°. The mean bond distances Si? S and Si? C are 215.2 pm and 187.4 pm, respectively. Some structural details are discussed.     

N‐Benzoylthiourea

In the title compound, C₈H₈N₂OS, strong intramolecular N—H⋯O hydrogen bonds [N⋯O = 2.669 (3) and 2.618 (3) Å] form almost planar six‐membered rings and enforce the conformation of the mol­ecule. Two kinds of intermolecular N—H⋯S hydrogen bonds [N⋯S = 3.309 (3)–3.456 (2) Å] between two symmetry‐independent mol­ecules form consecutive dimers that expand in ribbons along the [100] direction.     

1,4,4‐Tri­methyl‐9‐phenyl‐8‐oxa‐9‐aza­bi­cyclo­[3.2.2]­non‐6‐en‐2‐one

The structure of the adduct of eucarvone with nitro­so­benzene, C₁₆H₁₉NO₂, is reported. The [3.2.2] bicyclic system corresponds to two seven‐membered rings in boat and distorted chair conformations and a six‐membered ring that adopts a distorted boat conformation. No conjugation is observed between the phenyl group and the N—O system. The packing is directed mainly by a C?O hydrogen bond, C—H?O‐(1 ? x, ?y, z) and by intermolecular C—H?π interactions.