A comparison of the coordination preferences of Zn, Co, and Cd(II) with the heteroscorpionate ligand (2-hydroxy-3-t-butyl-methylphenyl)bis (3,5-dimethylpyrazolyl)methane

Reaction of the Zn, Cd, or Co nitrate salts with the deprotonated ligand (2-hydroxy-3-t-butyl-methylphenyl)bis(3,5-dimethylpyrazolyl)methane (L1O^–) in methanol produced the following complexes: [(L1OH)Zn(NO₃)₂] in two isomorphs, a = 40.983(8) Å, b = 9.571(2) Å, c = 15.667(8) Å, = 90, = 106.38(1), = 90, C2/c, and a = 13.027(3) Å, b = 14.781(4) Å, c = 16.107(3) Å, = 90, = 105.30(1), = 90, P2₁/n; [(L1OH)Cd(pz)(NO₃)₂] a = 14.7476(2) Å, b = 13.5411(2) Å, c = 16.7223(2) Å, = 90, = 110.3840(10), = 90, P2₁/c; and [(L1O)Co(pz)(NO₃)] a = 11.4240(2) Å, b = 13.4498(2) Å, c = 13.8056(2) Å, = 105.2080(10), = 105.8130(10), = 112.7470(10), P . The Zn adopts a pseudotetrahedral four-coordinate geometry where the potentially tridentate ligand is actually bidentate with a protonated and uncoordinated phenoxy arm. The Co complex is pseudooctahedral six-coordinate where the phenoxy arm is deprotonated and coordinated. Finally the Cd complex is seven-coordinate but the metal is not coordinated through the phenoxy group that is again protonated.     

Crystal and molecular structure of: 5-(1-oxoethyl)-1-methyl-2-(5-bromo-6-methoxy-2-naphthyl)-6-oxabicyclo[3.2.1]octan-7-one and 5-(1-oxoethyl)-1-methyl-2-(5-bromo-6-methoxy-2-naphthyl)-6-oxabicyclo[3.2.1]octane

X-ray crystallographic studies of the two title compounds have shown that the molecules crystallize in the same triclinic space group, , with very similar cell dimensions. For C₂₁H₂₁BrO₄,a=12.056(5),b=13.206(5),c=7.595(3)Å, =90.38(3), =106.07(3) and =124.42(3)° and for C₂₁H₂₃BrO₃,a=12.076(6),b=13.090(5),c=7.490(3)Å, =92.65(5), =104.90(5) and =124.55(5)°. Both compounds possess the oxabicyclo[3.2.1]octane bridged ring system and differ only at the carbon to the ring oxygen where the Csp³ in the ether is replaced by Csp²=O in the lactone. Both cyclohexane rings adopt distorted chair conformations and the lactone and ether rings approximate closely to the envelope conformation. The bromine substituent at C(4) results in distortion of the naphthalene ring. Both molecules pack with the naphthalene rings parallel to each other with interplanar spacings of 3.71 Å in the ether and 3.66Å in the lactone.     

Crystal and molecular structure of cesium isothiocyanatotrimethylaluminate,Cs[Al(CH3)3NCS]

The crystal structure of the title compound has been determined from three-dimensional X-ray diffraction data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP2₁/c, witha = 8.849(4),b = 13.798(5),c = 7.943(4) Å, = 102.98(3) °, andD _x = 1.85g cm^–3 forZ = 4. The finalR factor for 1283 observed reflections is 0.046. The aluminum atom is bonded to the nitrogen atom of the thiocyanate ligand, where the Al-N bond length is 1.94(1) Å. The SCN is linear, and the CN-Al angle is 175(1) °. The cesium ion exhibits four contacts less than 3.60 Å: Cs C(thiocyanate) = 3.39(1) Å, Cs C(methyl) = 3.52(1) Å, Cs C.(methyl) = 3.56(1) Å, and Cs N = 3.575(9) Å. The closest Cs S is 3.772(3) Å.     

Synthesis and structural characterization of 2-mercapto-1-tert-butylimidazole and its Group 12 metal derivatives (HmimtBu)2MBr2 (M = Zn, Cd, Hg)

2-Mercapto-1-tert-butylimidazole (Hmim^tBu) and its Group 12 metal complexes (Hmim^tBu)₂ MBr₂ (M = Zn, Cd, Hg) have been readily prepared and structurally characterized. Whereas the former displays a dimeric structure in the solid state with two S H–N interactions linking each pair of molecules, the four-coordinate complexes exhibit distorted tetrahedral geometries with the S–M–S angles in the range 103.2–135.2. The average M–Br bond lengths are 2.401, 2.567, and 2.688 Å for M = Zn, Cd, and Hg, respectively, and the corresponding average M–S bond distances are 2.350, 2.540, and 2.467 Å. The average C–S bond length for all the complexes (1.72 Å) is only ca. 0.02 Å longer than the corresponding value in the free ligand. Hmim^tBu is orthorhombic, space group Pbca, a = 10.1571(5) Å, b = 9.7906(5) Å, c = 17.6616(9) Å, V = 1756.34(15) ų, Z = 8; (Hmim^tBu)₂ZnBr₂ is monoclinic, space group C2/c, a = 17.187(3) Å, b = 8.9908(17) Å, c = 15.560(3) Å, = 117.206(3), V = 2138.3(7) ų, Z = 4; (Hmim^tBu)₂CdBr₂ is triclinic, space group P , a = 7.4625(6) Å, b = 9.6149(9) Å, c = 31.020(3) Å, = 93.485(2), = 94.579(2), = 103.872(2), V = 2146.6(3) ų, Z = 4; (Hmim^tBu)₂HgBr₂ is monoclinic, space group P2₁/c, a = 6.8908(6) Å, b = 10.2397(9) Å, c = 29.859(3) Å, = 94.364(2), V = 2100.7(3) ų, Z = 4.     

Schiff bases and their complexes with metal ions. Part II. Structures of N-n-butyl-2-hydroxy-1-naphthaldimine and bis[N-n-pentyl-2-hydroxy-1-naphthaldiminato]nickel(II)

The Schiff base ligand (1), [C₁₅H₁₇NO] crystallizes in the monoclinic space group P2₁/c witha=10.054(3),b=10.313(3), c=13.173(4)Å, =107.42(4)°,V=1303.2(7)ų,Z=4,Dx=1.159 g cm^–3, and (MoK)=0.674 cm^–1. The C2-O[1.23(1)Å] and C3–C4 [1.33(2)Å] bond lengths are short, due to its quinoidal structure. In the Schiff base nickel complex (2), [Ni(C₁₆H₁₈NO)₂] the asymmetric unit is comprised of two half-complexes. It crystallizes in the triclinic space group witha=5.124(3),b=16.227(3),c=16.886(4)Å, =95.47(8), =96.00(1), =90.71(4)°,V=1389.6(9) ų,Z=2,Dx=1.289 g cm^–3, and (MoK) =12.1 cm^–1. The coordination of the Ni(II) ions are square planar with bond angles between 87.9(1) and 92.1(1)°. The Ni–O and Ni–N distances are 1.819(2), 1.922(2) and 1.823(2), 1.914(3)Å in these two complexes.     

A novel class of naturally occurring halogenated pyrroles, 1,1′-dimethyl-3,3′,4,4′,5,5′-hexabromo-2,2′-bipyrrole, 5,5′-dichloro-1,1′-dimethyl-3,3′,4,4′-tetrabromo-2,2′-bipyrrole, and 1,1′-dimethyl-3,3′,4,4′,5,5′-hexachloro-2,2′-bipyrrole

Crystal structure determinations of the three title hexahalogenated bipyrroles, (I) C₁₀H₆Br₆N₂, (II) C₁₀H₆Br₄Cl₂N₂, and (III) C₁₀H₆Cl₆N₂, reveal essentially planar pyrrole rings having dihedral angles of 64.7, 65.1, and 64.2° between the least-squares planes, favoring in each case a closer methyl–halogen conformation. All three complexes crystallize in the orthorhombic space group Pbcn with the following cell dimensions: (I) a = 12.654(3) Å, b = 8.853(2) Å, c = 13.753(3) Å, = = = 90°, Z = 4; (II) a = 12.438(6) Å, b = 8.753(6) Å, c = 13.696(3) Å, = = = 90°, Z = 4; (III) a = 12.088(6) Å, b = 8.566(4) Å, c = 13.486(8) Å, = = = 90°, Z = 4.     

Hydrogen-bonded networks formed by substituted 2,6-diarylpyrazines

The X-ray crystal structure of 2,6-bis(4-hydroxyphenyl)pyrazine and 2,6-bis(4carboxyphenyl)pyrazine are reported. The structure of the 2,6-bis(4-carboxyphenyl) pyrazine dimethylsulfoxide complex (C₁₈H₁₂N₂O₄)(C₂H₆OS) is triclinic, P-1, with a = 7.9933(8), b = 10.7165(10), c = 12.1337(12) Å, = 66.385(2), = 84.070(2), = 77.219(2). The structure comprises stacked two-dimensional sheets of the hydrogen bonded complex. The two-dimensional sheets comprise hydrogen-bonded ribbons of the (carboxyphenyl)pyrazine that are connected by bridging hydrogen bonds to the dimethylsulfoxide. The structure of 2,6-bis(4-hydroxyphenyl)pyrazine, C₁₆H₁₂N₂O₂, is monoclinic, P2₁/c, with a = 10.6107(13) Å, b = 14.6743(18) Å, c = 8.3772(10) Å and = 104.982(2). The structure reveals that two-dimensional hydrogen-bonded sheets are formed with pyrazine–phenol and phenol–phenol hydrogen bonds.     

N-Arylmaleimide derivatives

Nine phenyl substituted N-phenylmaleimide monomers for photopolymerization studies have been characterized by x-ray crystallography. Structures for N-(2-t-butylphenyl)maleimide (1), P2₁/n, a = 10.197(3) Å, b = 11.904(4) Å, c = 10.496(5) Å, = 100.61(3)° N-(2-trifluoromethylphenyl)maleimide (2), P2₁/c, a = 11.763(8) Å, b = 10.699(9) Å, c = 8.284(5) Å, = 90.02(5)° N-(2,6-diisopropylphenyl)maleimide hemibenzene solvate (3), Pc, a = 16.747(6) Å, b = 8.552(3) Å, c = 12.899(4) Å, = 105.08(3)° N-(2,6-diisopropylphenyl) maleimide (unsolvated) (4), C2/c, a = 28.146(10) Å, b = 8.434(4) Å, c = 12.881(4) Å, = 92.20(4)° N-(2-bromo-3,5-bis(trifluoromethyl)phenyl) maleimide (5), P2₁/n, a = 8.7115(16) Å, b = 16.125(3) Å, c = 9.6707(19) Å, = 99.757(15)° N-(2-phenylphenyl)maleimide (6), P2₁/n, a = 8.519(4) Å, b = 13.742(5) Å, c = 11.147(4) Å, = 92.25(3)° N-(4-methoxyphenyl)maleimide (7), P2₁/n, a = 9.320(3) Å, b = 6.621(2) Å, c = 16.059(6) Å, = 99.58(3)° N-(2-trifluoromethylphenyl)-2-methylmaleimide (8), Fdd2, a = 43.362(12) Å, b = 8.202(2) Å, c = 12.720(4) Å and N-(2-trifluoromethylphenyl)-2-methanosuccinimide (9), Cc, a = 7.708(2) Å, b = 22.191(9) Å, c = 7.137(2) Å, = 115.76(2)° are described. Molecules with bulky 2-substituents show larger rotations between the mean phenyl and maleimide ring planes, and varying degrees of distortion to the imide group.     

Complexation with diol host compounds. Part 3. Molecular inclusion of 4-methylcyclohexanone and 2-methylcyclohexanone by the host,trans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene

The structures of the 12 molecular complexes oftrans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with 4-methylcyclohexanone (1) and with 2-methylcyclohexanone (2) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P2₂/c,a=8.838(2) Å,b=8.92(1) Å,c=20.879(8)=Å,=98.67(2)°,V=1627(2) ų,Z=2 andR=0.062 for 2201 unique MoK reflections; Compound (2):P¯1,a=8.917(3) Å,b=9.900(2) Å,c=11.250(4) Å,a=68.72(2)°,=64.39(3)°, =74.86(2)°,V=828.1(5) ų,Z=1 andR=0.098 for 2563 unique reflections. Both inclusion compounds exhibit O-HO=C hydrogen bonding interactions. The thermal properties of these compounds have been characterized by DTA and TGA thermograms.     

Crystal structures of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes

The crystal and molecular structure of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes (1–5) have been determined by single crystal X-ray diffraction analysis. In all five compounds, the tetraazabicycloundecane portion of the molecule assumes a cage-like, folded structure with the aryltriazene moieties aligned approximately parallel; the structure is held in the folded configuration by either intramolecular or intermolecular – stacking forces. Crystal data: 1 C₁₉H₂₂N₁₀O₄, monoclinic space group P2₁/c, a = 10.1846(7), b = 9.9556(7), c = 20.819(2) Å, = 98.725(1)°, V = 2086.5 (3) ų, Z = 4; 2 C₂₃H₂₈N₈O₄, triclinic, space group P, a = 6.7064(7), b = 12.9662(14), c = 14.054(2) Å, = 94.796(2), = 91.621(2), = 104.836(2)°, V = 1175.7(2) ų, Z = 2; 3 C₁₉H₂₂N₁₀O₄, monoclinic, space group P2₁/c, a = 14.237(2), b = 13.520(2), c = 11.5805(12) Å, = 113.514(2)°, V = 2044.0(4) ų, Z = 4; 4 C₂₁H₂₂N₁₀, monoclinic, space group C2/c, a = 54.247(3), b = 11.5531(7), c = 12.9670(7) Å, = 95.710(1)°, V = 8086.4(8) ų, Z = 16; 5 C₂₅H₃₂N₈ 0₄, monoclinic, space group P2₁/c, a = 10.2908(7), b = 16.5687(12), c = 15.1662(10) Å, = 94,188(1)°, V = 2579.0(3) ų, Z = 4.     

Chemical preparation and crystal structure of 6′-butoxy-2,6-diamino-3,3′azo-dipyridine monohydrate

Chemical preparation, X-ray single crystal, and calorimetric studies of C₁₄H₁₈N₆O·H₂O are described. The compound crystallizes in the triclinic space group, P with unit cell dimensions: a = 6.2640(3), b = 10.9840(4), c = 12.2220(3) Å, = 105.03(2), = 96.96(2), = 101.6(2)°, V = 712.10(5) ų, and Z = 2. The 6-butoxy-2,6-diamino-3,3-azo-dipyridine monohydrate structure is built up from organic layers parallel to the (120) plane linked via O—H···N bond.     

Syntheses and structures of N-phenylmaleimidetriazoles and by-products

The syntheses, properties, and structures of N-phenylmaleimidetriazole derivatives are described. Intermediates and by-products are also discussed. 1b. a = 43.997(7) Å, 5.7610(9) Å, 8.245(1) Å, = 99.339(4), C₂/c; 2a. a = 13.646(4) Å, b = 7.744(2) Å, c = 10.612(3) Å, = 91.979(6), P2₁/c. 3a. a = 22.245(1) Å, b = 22.245(1) Å, 10.010(1) Å, P42/n. 3a. a = 11.727(2) Å, b = 14.075(3) Å, c = 16.080(3) Å, = 105.859(3), = 105.331(3), = 98.187(3), P-1. 3b. a = 8.561(3) Å, b = 14.755(5) Å, c = 22.771(7) Å, = 97.006(5), P2₁/c. 3c. a = 10.500(2) Å, b = 12.189(2) Å, c = 13.040(2) Å, = 109.091(3), = 106.089(3), = 101.022(3), P-1. 8a. a = 16.389(8) Å, b = 5.749(3) Å, c = 19.316(3) Å, = 97.467(9), P2₁/n. 8b. a = 5.822(2) Å, b = 10.114(3) Å, c = 16.705(4) Å, = 84.681(5), = 82.840(5), = 75.769(4), P-1. 9b. a = 11.251(1) Å, 13.335(3) Å, 13.376(3) Å, = 102.456(4), P2₁/n. 9c. a = 15.836(3) Å, b = 8.236(2) Å, c = 5.447(3) Å, = 92.551(3), P2₁/c. 10a. a = 13.177(2) Å, b = 14.597(2) Å, c = 5.5505(8) Å, = 110.979(2), Cc. 11a. a = 14.720(2) Å, b = 13.995(2) Å, c = 38.245(6) Å, = 94.430(3), P2₁/n. 12b. a = 15.067(5) Å, b = 20.378(6) Å, c = 8.669(5) Å, = 99.16(4), = 99.32(3), = 105.23(3), P-1. 13b. a = 8.2824(6) Å, b = 10.5245(7) Å, c = 15.518(1) Å, = 92.305(1), = 100.473(1), = 100.124(1), P-1. 15a. a = 15.357(3) Å, b = 7.778(2) Å, c = 22.957(2) Å, Pbca. 16b. a = 18.0384(4) Å, b = 12.474(3) Å, c = 20.078(5) Å, Pbca.     

Terbium and holmium trans-2,3-dimethylacrylic acid complexes with 1,10-phenanthroline

Novel dinuclear complexes, [REL₃(phen)]₂ (where RE = Tb, Ho; HL = trans-2,3-dimethylacrylic acid; phen = 1,10-phenantheoline), were synthesized and determined by elemental analysis, infrared absorption spectra (IR), thermogravimetric analysis (TGA), and X-ray diffraction. The Tb complex crystallizes in space group P2_1/n with the cell dimensions a = 12.939(2) Å, b = 13.018(2) Å, c = 15.400(3) Å and = 94.72(1)°. The Ho complex crystallizes in P ⁽⁹⁾ with a = 12.406(3) Å, b = 13.280(3) Å, c = 9.823(2) Å, = 110.80(2)°, = 103.42(2)°, = 63.67(1)°. The Tb atom is nine coordinate and the separation of Tb...Tb* is 3.97 Å. The Ho atom is eight coordinate and the separation of Ho...Ho* is 4.01 Å.     

Short H· · ·H distances in norbornene derivatives

A short H···H intramolecular interaction was reported previously for an anhydride of syn-sesquinorbornene. The synthesis and structure of a such an anhydride with an additional five-membered dithiole ring has been investigated. While hydrogen atom positions are not accurately located, the 1.62 Å separation indicates this molecule is a candidate for the shortest H···H interaction. Two cycloadducts of norbornadiene, which literature suggests might exhibit additional short interactions, are reported also; however, the isomers with minimal intramolecular interactions are the isolated products. C₂₂H₂₀O₃S₂, 3, crystallizes in P with a = 10.881(4), b = 13.712(8), C = 6.548(8) Å, = 101.32(6), = 107.49(5), = 90.49(4)°, D _calc = 1.445 g cm^–3, and Z = 2, C₂₁H₂₀O₄Cl₈, 5, in P2₁/n with a = 8.168(2), b = 13.488(4), c = 23.500(6) Å, = 94.72(2)°, D _calc = 1.597 g cm^–3, and Z = 4, C₂₁H₂₈O₄, 6, in P> with a = 12.667(2), b = 12.792(2), c = 12.540(2) Å, = 113.51(1), = 98.18(1), = 74.39(1)°, D _calc = 1.276 g cm^–3, and Z = 4.     

Synthesis and crystal structure of 3,5-di(2-propenyl)-6-phenyl-1,3,5-triazine-2,4-dione and 2-dimethylamino-4-ethoxycarbonylmethoxy-6-phenyl-1,3,5-triazine

The title compound 3,5-di(2-propenyl)-6-phenyl-1,3,5-triazine-2,4-dione has been synthesized by the reaction of 6-phenyl-1,3,5-triazine-2,4-dione with allyl bromide. Its structure was determined by X-ray single crystal diffraction. The crystal belongs to orthorhombic, space group Pbca with the following crystallographic parameters: a = 16.282(4) Å, b = 8.888(2) Å, c = 19.281(5) Å, = 90°, = 90°, = 90°, = 0.088 mm^–1, V = 2790.1(13) ų, z = 8, Dx = 1.282 mg/m³, F(000) = 1136, T = 293(2) K, 2.11° 25.02°, the final R factor: R ₁ = 0.0430, wR₂ = 0.0981. The X-ray results demonstrate that the reaction of 6-phenyl-1,3,5-triazine-2,4-dione with allyl bromide in the presence of N,N-dimethylformamide and potassium carbonate yields the N-alkylated product. The title compound 2-dimethylamino-4-ethoxycarbonylmethoxy-6-phenyl-1,3,5-triazine has been synthesized by a new reaction, in which the solvent N,N-dimethylformamide involves. Its structure was determined by X-ray single crystal diffraction. The crystal belongs to triclinic, space group P-1 with the following crystallographic parameters: a = 7.977(2) Å, b = 10.394(3) Å, c = 10.837(3) Å, = 111.774(5)°, = 104.050(5)°, = 99.446(5)°, = 0.093 mm^–1, V = 776.6(4) ų, z = 2, Dx = 1.293 mg/m³, F(000) = 320, T = 293(2) K, 2.14° 25.03°, the final R factor: R ₁ = 0.0582, wR ₂ = 0.1399. The distance of N(4) C(2) (1.339 Å) is much shorter than the length of normal C N (1.47 Å) and very close to that of C-N (1.33 Å), which is indicative of the significant double bond character.     

Structure of bis(2-amino-5-methylpyridinium) tetrachlorozincate at 298 and 150 K

Reaction of 2-amino-5-methylpyridine with zinc chloride and HCl in aqueous solution yields bis(2-amino-5-methylpyridinium) tetrachlorozincate. The complex crystallizes in the monoclinic space group P2₁/c, with minimal tetrahedral distortion of the ZnCl₄ ^2– ion at both 298 and 150 K; at 298 K, a = 8.090(2) Å, b = 14.795(6) Å, c = 15.850(4) Å, = 101.93 (2); at 150 K, a = 8.0986(2) Å, b = 14.7190(5) Å, c = 15.7684(7) Å, = 102.862(2). The anisotropic cell contraction results in significant changes in nonbonding Cl Cl contacts.     

Structures and nonlinear optical properties of polar 2-amino-1,2,3-triazolequinone derivatives

A series of phenyldialkylamine, dimethoxyphenyl, and nitrothiophene derivatives of 2-amino-1,2,3-triazolequinones was characterized by NMR, IR, mass spectroscopy, cyclic voltammetry, and chemical analyses. The solvatochromic procedure was used to evaluate the potential of nine compounds for nonlinear optical applications, and the possible failure of this model is discussed. The crystal structures of seven compounds were determined: (4) P2₁/c, a = 15.430(3) Å, b = 7.633(2) Å, c = 15.940(3) Å, = 105.19(3)° (5) P2₁/c, a = 20.201(2) Å, b = 9.6579(9) Å , c = 18.517(2) Å, = 95.907(2)° (6) P-1, a = 7.769(2) Å, b = 8.515(3) Å, c = 17.312(5) Å, = 89.347(7)°, = 83.219(6)°, = 86.001(7)° (7) P-1, a = 8.1365(7) Å, b = 8.9605(8) Å, c = 11.630(1) Å, = 79.553(2)°, = 75.048(2)°, = 82.080(2)° (8) P-1, a = 8.298(3) Å, b = 9.720(3) Å, c = 10.033(3) Å, = 84.803(6)°, = 83.735(6)°, = 77.659(5)° (10) P2₁/n, a = 8.4300(7) Å, b = 13.980(1) Å, c = 13.975(1) Å, = 106.590(2)° (12) P2₁/n, a = 7.715(2) Å, b = 14.206(3) Å, c = 12.758(3) Å, = 91.016(5)°.     

Crystal structures of five policyclic compounds related to the natural product forskolin

(3(Z),4,6a,9a,9b)-(±)-3a,4,6a,7,8,9,9a,9b-octahydro-4,7,7, 9b-tetramethyl-3a-[3-(methoxymethyloxy)-3-methyl-1-butenyl]-5H-naphto[1,8-de]-1,3-dioxin-6-one (I), C₂₂H₃₆O₅,M _r=378.51, monoclinic,P2₁/n,a=6.330(1),b=14.576(2),c=22.837(2)Å,=93.04(1)°,V=2104.1(2)ų,Z=4,D _c=1.19 Mg/m³, (MoK)=0.71069Å,=0.8 cm^–1,F(000)=832,T=298 K,R=0.054 for 1971 observed reflections; (7a,10a,10b,12)-(±)-7a,9, 10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6,-de][1,3,2]-benzodioxin-11-one (II), C₂₀H₂₉O₄,M _r=334.5, triclinic,P-1,a=10.595(2),b=12.152(1),c=8.073(1)Å,=106.53(1),=105.65(1), =66.29(1)°,V=897.9(2)ų,Z=2,D _c=1.24 Mg/m³, (MoK)=0.71069Å,=0.8 cm^–1,F(000)=362,T=298 K,R=0.046 for 2848 observed reflections; (7a,10a,10b,12, 12a)-(±)-7a,9,10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6-de][1,3,2]-benzodioxin-11, 12-diol (III), C₂₀H₃₂O₅ (two molecules in the asymmetric unit),M _r=352.2, triclinic,P-1,a=12.948(3),b=13.615(3),c=12.197(4)Å,=101.16(2),=111.88(2), =69.48(2)°,V=1863.8(9)ų,Z=2,D _C=1.26 Mg/m³,(MoK)=0.71069 Å,=0.8 cm^–1,F(000)=768,T=298 K,R=0.060 for 4570 observed reflections; 4-acetoxy-4-[[(4a,5,8a)-(±)-hexahydro-4a,6,6-trimethyl-4H-1,3-benzodioxin-4-one]-5-yl]butan-2-one (IV), C₁₇H₂₆O₆,M _r=326.4, monoclinic,P2₁/c,a=10.495(2),b=12.050(2),c=14.216(2)Å,=108.51(1)°,V=1704.8(5)ų,Z=4,D _c=1.27 Mg/m³,(MoK)=0.71069 Å,=0.9 cm^–1,F(000)=704,T=298 K,R=0.049 for2455 observed reflections; (3a,4,5,6,6a,9a,9b)-(±)-4,5-epoxy-decahydro-3, 3a-dihydroxy-2-ethoxy-4,7,7,9b-tetramethyl-naphto-[1,8-bc]-pyran-6-ol-acetate (V), C₂₀H₃₂O₇,M _r=383.5, monoclinic,C2/c,a=10.353(2),b=17.975(3),c=21.188(3)Å,=91.29(1)°,V=3942(1)ų,Z=8,D _c=1.29 Mg/m³,(MoK)=0.71069 Å,=0.8 cm^–1,F(000)=1664,T=298 K,R=0.051 for 2120 observed reflections. We report here the complete structures of four decalin derivatives (compoundsI, II, III, V) and one related compound (compoundIV) synthetized in order to find an efficient synthetic approach for the natural productforskolin.     

Crystal and molecular structure of a hexaazamacrocycle

The crystal and molecular structure of the hexaazamacrocycle C₂₄H₁₄N₆ has been determined from X-ray diffractometer data. The crystals are monoclinic, space groupP2₁/c witha = 4.416(1),b = 9.972(4),c = 18.955(12) Å, = 95.48(4) °, andZ = 2. The structure was derived from 536 reflections using direct and Fourier methods and was refined by least squares toR = 0.038. The polar molecules form stacks along thea axis with an inclination of 68 ° and an interplanar distance of 3.32 Å. The size of the central hole of the molecule is defined by the diagonal distances N(2) N(2) = 3.681(10) and N(3) N(3) = 3.771(9) Å of theo-phenanthroline nitrogens. This is too small to accommodate Pd²⁺ or Pt²⁺ in the hole.     

Structural characterization of Elisabatin B and Elisabatin C

X-ray structures of Elisabatin B (1) and Elisabatin C (2) have been determined. Crystal data for 1: Triclinic, P (No. 2), a = 7.528(2) Å, b = 9.404(2) Å, c = 11.414(2) Å, = 75.363(3)°, = 86.668(4)°, = 89.683(4)°, and Z = 2. Crystal data for 2: Monoclinic, P2₁/c (No. 14), a = 8.242(2) Å, b = 14.870(2) Å, c = 13.060(2) Å, = 101.458(3)°, and Z = 4. Both compounds are highly unsaturated leading to extended aromatic conjugation. They show different intermolecular O–HO hydrogen bonds, via which 1 forms dimers, and 2 zig-zag polymeric chains.