The preparation and crystal structures of some tricarbonylmanganese(I) octahedral complexes containing the 1,1-dimethylamino-2,2-diphenylphosphinoethane ligand

Four new complexes of (pn) the titled ligand have been prepared and characterized: (CO)₃Mn(pn)Br, 1; (CO)₃Mn(pn)N₃, 2; the triazalato (tz) complex, (CO)₃Mn(pn)(tz), 3 and [(CO)₄Mn(pn)]BF₄, 4. Crystal structures for the first three of these were determined. Crystal data for 1, monoclinic crystal system, space group = C2, a = 17.8587(6) Å, b = 7.9611(3) Å, c = 14.2349(4) Å, = 90.281(1)°, V = 2023.82(12) ų, Z = 4; for 2, monoclinic crystal system, space group = P2₁/c, a = 8.8933(14) Å, b = 13.844(2) Å, c = 16.361(3) Å, = 95.712(3)°, V = 2004.4(6) ų, Z = 4; for 3, orthorhombic crystal system, space group = Pbca, a = 17.9097(4) Å, b = 13.1308(4) Å, c = 21.2838(6) Å, V = 5005.3(2) ų, Z = 8.     

The crystal and molecular structures of 9,10-dihydro-9, 10-ethano- and etheno-anthracenes

As part of our investigation on histamine receptor antagonists, the structures of two 9-10-dihydroanthracene derivatives are reported: 4: C₂₂H₂₈N₂; hexagonal, P6₁; a = 10.014(1), c = 34.556(7) Å; V = 3001.0(7)ų; and Z = 6; 9:C₁₉H₁₉N: triclinic, P-1; a = 8.427(2), b = 12.806(3), c = 15.292(3) Å, = 70.27(3), = 80.83(3), = 72.98(3)°; V = 1482.0(6) ų; and Z = 4. All non-aromatic rings in both molecules adopt a similar conformation. However, the three six-membered rings in the etheno-anthracene structure adopt a more regular boat form in spite of two sp² carbon bridged atoms.     

Pseudoacids. III: formation and structures of new cyclic oxocarboxylic acids

Crystal and molecular structures for aryl- and benzyl-substituted 3-hydroxy-3,4-dihydroisobenzopyran-1-one are described. For the 4,4-dimethyl derivative, two monoclinic modifications are produced on sublimation: (1) P2₁/c, a = 23.668(6) Å b = 11.749(4) Å c = 7.215(2) Å = 96.70(2); V = 1992.6(10) ų; (2) P2₁/c, a = 11.509(4) Å, b = 12.429(4) Å, c = 6.933(2) Å, = 91.12(3), V = 991.6(6) Å. In both, hydroxy groups are pseudoaxial, and molecules form dimeric complementary but noncooperative hydrogen bonds. In the 6-methoxy derivative (3), P2₁/c; a = 14.185(7) Å b = 4.105(4) Å c = 15.598(13) Å = 98.59(6); V = 898.1(10) ų, the hydroxy group is pseudoequatorial, and the intermolecular hydrogen bonding forms infinite chains. In the 4,4-dimethyl-7-nitro derivative (4), C2/c, a = 19.365(4), b = 8.425(2), c = 13.464(4), = 92.62(2), V = 2194.2(7) ų, the hydroxy group is pseudoaxial, and the intermolecular hydrogen bonding forms chains. Compared to the unmethylated compounds, the interbond angles within the ring at the dimethylated carbon are contracted.     

Crystal structures of the cobalt(III), nickel(II), copper(II), and zinc(II) complexes of 2-thio-6-picoline N-oxide

Structures of the following compounds have been solved: tris(2-thio-6-picoline N-oxide)cobalt(III), [Co(6MOS)₃], orthorhombic, Pca2₁, a = 17.871(3), b = 14.061(2), c = 15.964(2) Å, V = 4011(1) ų, Z = 8, and = 1.193 mm^–1; bis (2-thio-6-picoline N-oxide)nickel(II), [Ni(6MOS)₂], orthorhombic, Pbca, a = 15.602(8), b = 13.606(4), c = 13.348(8) Å, V = 2833(4) ų, Z = 8, and = 1.655 mm^–1; bis(2-thio-6-picoline N-oxide)copper(II), [Cu(6MOS)₂], orthorhombic, Pbca, a = 13.914(5), b = 12.984(5), c = 15.663(6) Å, V = 2830(2) ų, Z = 8, and = 1.836 mm^–1; and bis(2-thio-6-picoline N-oxide)zinc(II), [Zn(6MOS)₂], triclinic, P – 1, a = 7.9737(8), b = 11.7786(9), c = 7.9206(8) Å, = 104.502(7), = 104.495(8), = 93.445(8)°, V = 691.3(1) ų, Z = 2, and = 2.106 mm^–1. The steric effect of the methyl group in the six-position of the N-oxide ring is considered in comparing these structures to complexes of 2-thiopyridine N-oxide.     

Crystal structures of diphosphinated group 6 Fischer alkoxy carbenes

The crystal structures of four diphosphinated Group 6 Fischer alkoxy carbenes with the compositions fac-(dppe)(CO)₃M–C(OR)(R) (R = Me, R = Et, M = Cr, 1; R = Ph, R = Me, M = Cr, 2; R = Me, R = Me, M = W, 3; R/OR = 3-methyl-2-oxacyclopentylidenyl, M = Cr, 4) have been determined at 243 K. Compound 1 crystallizes in the monoclinic system, space group P2₁/c with a = 11.2243(11) Å, b = 18.5998(18) Å, c = 15.1260(15) Å, = 107.056(4), V = 3019.0(5) ų, and Z = 4. Compound 2 crystallizes in the monoclinic system, space group P2₁/c with a = 11.8102(9) Å, b = 18.3152(14) Å, c = 15.0262(12) Å, = 93.753(3), V = 3243.3(4) ų, and Z = 4. Compound 3 crystallizes in the monoclinic system, space group P2₁/c with a = 11.3458(6) Å, b = 18.5772(9) Å, c = 15.3883(8) Å, = 108.576(6), V = 3074.5(3) ų, and Z = 4. Compound 4 crystallizes in the orthorhombic system, space group Pna2₁ with a = 22.6509(14) Å, b = 9.8118(6) Å, c = 13.7507(8) Å, V = 3056.0(3) ų, and Z = 4. Steric repulsions with the dppe ligand favor a conformation with the alkoxy moiety directed toward the dppe backbone, in an E geometry, in 1–4.     

Structural studies of N-2-(6-picolyl)-N′-tolylthioureas

Reaction of 2-amino-6-picoline with 2-, 3-, and 4-tolyl isothiocyanates produces the three N-2-(6-picolyl)-N-tolylthioureas, 6PicTu2T, 6PicTu3T, and 6PicTu4T. 6PicTu2T is mono-clinic, space group P2₁/n with a = 8.1700(3) Å, b = 25.5840(6) Å, c = 12.6840(5) Å, = 98.8750(16)°, and V = 2619.5(2) ų with Z = 8, for d _calc = 1.305 g/cm³. 6PicTu3T is monoclinic, space group C2/c with a = 23.879(3) Å, b = 6.744(3) Å, c = 17.116(10) Å, = 99.26(4)°, and V = 2720(3) ų with Z = 8, for d _calc = 1.257 g/cm³. 6PicTu4T is triclinic, space group P-1 with a = 8.829(6) Å, b = 8.8950(15) Å, c = 10.495(3) Å, = 68.63(3)°, = 72.19(4)°, = 63.06(4)°, and V = 681.2(5) ų with Z = 2, for d _calc = 1.255 g/cm³. Intermolecular hydrogen bonding involving the thione sulfur and the NH hydrogen and the planarity of the thiourea are affected by the position of substitution on the aryl ring. ¹H NMR studies in CDCl₃ show the NH hydrogen resonance considerably downfield from other signals in the spectrum of each thiourea. The enthalpies of fusion of the present thioureas reflect the extent of intermolecular hydrogen bonding and are compared to other heterocyclic thioureas.     

Structures of divalent transition metal salts of 4-aminonaphthalene-1-sulfonate: unexpected variations in layering pattern

Salts of 4-aminonaphthalene-1-sulfonate with divalent Mg, Mn, Co, and Ni cations have been crystallized and their structures determined by single crystal X-ray methods. The Mg and Mn salts are isostructural. Crystal data for hexa-aquamagnesium(II) 4-aminonaphthalene-1-sulfonate dihydrate, [Mg(H₂O)₆](H₂NC₁₀H₆SO₃)₂ 2H ₂O: monoclinic, P2₁/c, Z = 2, a = 8.622(3), b = 7.043(3), c = 23.178(3) Å, =93.78(2)°, V = 1404.3(7) ų; hexa-aquamanganese(II) 4-aminonaphthalene-1-sulfonate dihydrate, [Mn(H₂O)₆](H₂NC₁₀H₆SO₃)₂ 2H ₂O: monoclinic, P2₁/c, Z = 2, a = 8.652(3), b = 7.031(4), c = 23.402(2) Å, =93.09(2)°, V = 1421.5(9) ų. The structures are composed of alternating layers of octahedral metal–aqua complexes and sulfonate anions linked by an extensive network of hydrogen bonds. The extra water molecules of crystallization are located in the hexa-aquametal cation layers. The repeat unit along the c axis is a double layer. The Co and Ni compounds are isostructural with each other, but compared to the Mg and Mn compounds, have a strikingly different structure. Crystal data for hexa-aquacobalt(II) 4-aminonaphthalene-1-sulfonate trihydrate, [Co(H₂O)₆](H₂NC₁₀H₆SO₃)₂ 3H ₂O: orthorhombic, Pbca, Z = 8, a = 8.518(1), b = 14.327(2), c = 45.367(6) Å, V = 5536(1) ų; hexa-aquanickel(II) 4-aminonaphthalene-1-sulfonate trihydrate, [Ni(H₂O)₆](H₂NC₁₀H₆SO₃)₂ 3H ₂O: orthorhombic, Pbca, Z = 8, a = 8.4976(6), b = 14.288(1), c = 45.076(3) Å, V = 5472.9(7) ų. These structures also contain layers of octahedral hexa-aquametal complexes and additional water molecules of crystallization sandwiched by layers of sulfonate anions, however the stacking pattern is more complex with a quadruple layer repeat unit and two different types of anion layers.     

Synthesis, spectroscopy, and X-ray structures of fac-(CO)3(dppe)MnSC(S)H, fac-(CO)3(dppe)ReSC(S)H, fac-(CO)3(dppp)ReSC(S)H, and fac-(CO)3(dppb)ReSC(S)H

The monodentate dithioformato complexes, fac-(CO)₃(dppe)MnSC(S)H (1), fac- (CO)₃(dppe)ReSC(S)H (2), fac-(CO)₃(dppp)ReSC(S)H (3), and fac-(CO)₃ (dppb)ReSC(S)H (4), where dppe is 1,2-bis(diphenylphosphino)ethane, dppp is 1,3-bis(diphenylphosphino)propane, and dppb is 1,4-bis(diphenylphosphino)butane, were synthesized from the treatment of the corresponding hydrides, fac-(CO)₃ (P-P)MSC(S)H with CS₂. Compounds 1–4 crystallize in the monoclinic crystal system: for 1, space group = P2₁/c, a = 15.3139(3) Å, b = 9.7297(4) Å, c = 19.0991(6) Å, = 105.928(1), V = 2736.5 ų, Z = 4; for 2, space group = P2₁/c, a = 15.6395(8) Å, b = 9.8182(5) Å, c = 19.4153(11) Å, = 106.741(1), V = 2854.9(3) ų, Z = 4; for 3, space group = P2₁/n, a = 11.3570(10) Å, b = 19.465(2) Å, c = 15.5702(14) Å, = 104.776(2), V = 3328.3(5) ų, Z = 4; and for 4, space group = C2/c, a = 32.078(2) Å, b = 10.4741(6) Å, c = 19.0608(9) Å, = 94.315(2), V = 6386.1(6) ų, Z = 8.     

Di- and triindolylmethanes: molecular structures and spectroscopic characterization of potentially bidentate and tridentate ligands

4-Bromophenyldi(3-methylindol-2-yl)methane (2) and 2-methoxyphenyldi(3-methylindol-2-yl)methane (3) were prepared by sulfuric-acid-catalyzed reactions of 3-methylindole with 4-bromobenzaldehyde and o-anisaldehyde, respectively. Di(3-methylindol-2-yl)phenylmethane (1) and tri(3-methylindol-2-yl)methane (4) were similarly prepared as described previously. Spectroscopic data (¹H, ¹³C NMR) and the X-ray crystal structures for 1 C₂H₅OH and 2–4 are reported. The molecular structure of 1 C₂H₅OH shows hydrogen bonding of both indolyl NH protons to the oxygen of an ethanol molecule. Crystal data for 1 C₂H₅OH: Orthorhombic, Pca2₁, a = 23.9782(17) Å, b = 8.4437(7) Å, c = 11.3029(9) Å, V = 2288.4(3) ų, R ₁ = 0.0597. Crystal data for 2: Orthorhombic, P2₁2₁2₁, a = 8.911(3) Å, b = 9.584(4) Å, c = 24.040(11) Å, V = 2053.0(14) ų, R ₁ = 0.0454. Crystal data for 3: Monoclinic, P2₁/c, a = 9.737(2) Å, b = 25.035(6) Å, c = 9.359(2) Å, = 114.853(4), V = 2070.2(8) ų, R ₁ = 0.0511. Crystal data for 4: Trigonal, R3, a = 14.2214(10) Å, c = 9.6190(10) Å, V = 1684.8(2) ų, R ₁ = 0.0425.     

Stereochemistry of racemic hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-dienenickel(II) thiocyanate,C16H32N4Ni(SCN)2 · H2O

The diamagnetictrans-diene thiocyanate salt of the macrocyclic hexamethyl-1,4,8,11-tetraazacyclotetradecadienenickel(II) complex crystallizes in the triclinic system with unit cell dimensions:a = 7·334(4),b = 8·808(6),c = 21·04(2) Å; = 63·7(0·9), = 103·8(1·4), = 110·2(1·3) °; space groupP¯1;Z = 2. The positions of all 62 atoms of the formula unit C₁₆H₃₂N₄Ni(SCN)₂.H₂O have been determined and refined by least-squares methods toR= 0·071 for 3536 X-ray diffractometric reflections. The optical activity of the two amine groups yields a racemic isomer. The only local symmetry element of the macrocyclic complex is the twofold rotation axis with the N-H bonds oriented on the same side of the approximate ligand plane. Both the C(CH₃)₂ and the imine groups are in atrans-configuration in the ring. The space group ensures that the crystal is a racemate, containing equal numbers of both enantiomers. One of the (SCN)^– groups is at a distance Ni-S 3·28 Å, the other one is 4·65 Å. No rotational disorder of the CH₃ groups has been observed. The three C-H bonds of the CH₃ groups are in approximately antiprismatic orientations with respect to the three -bonds in the case of bonding to a C(sp³) atom. The average of the C(sp³)-C(sp²) bond lengths is 1·53 Å, and the mean value for the C(sp³)-C(sp²) bonds is 1·50 Å, with 3 = 0·03 to 0·04 Å. The distances N(sp²)-C(sp³) 1·47 Å and 1·48 Å are significantly longer than the bond lengths N(sp²)=C(sp²) of 1·28 and 1·30 Å.     

Design, synthesis, and structure of novel cesium receptors

The podand, bis(2-methoxyphenoxy)m-xylene (1), was designed and synthesized as a potential host for the cesium ion. Its structure was determined by single crystal X-ray diffraction. It crystallizes in P2₁/c with cell dimensions: a = 8.5723(7) Å, b = 8.3931(14) Å, c = 25.2879(26) Å, = 96.224(9), and V = 1808.7(4) ų. A crown derivative, tribenzo-21-crown-6 (2), was also prepared and structurally characterized. It also crystallizes in P2₁/c with cell dimensions: a = 15.5825(13) Å, b = 15.8648(16) Å, c = 8.8266(7) Å, = 95.247(6), and V = 2172.9(3) ų. The structures exhibit hydrogen bonding, and are evaluated in terms of complementarity and preorganization for cesium binding.     

Cage-annulated thiacrown ethers and thiacryptands

A series of cage-annulated sulfur-containing crown ethers and cryptands have been synthesized as possible specific metal host systems. The synthesis and structures of seven compounds are described, including a thiacryptand complex with Hg(II). The trishomocubane cage is essentially spherical except for a methylene group, which imparts no steric restrictions, and two disordered superimposed orientations occur in most structures. This superposition of four- and five-membered rings usually cannot be resolved into separate entities, resulting in distorted distances, angles, and thermal parameters for the cage. (3) I4₁ cd, a = 13.207(3) Å, b = 13.207(3) Å, c = 35.876(12) Å; (10) C2, a = 14.551(2) Å, b = 10.028(1) Å, c = 10.491(1) Å, = 107.108(2)°; (14) P2₁/n, a = 10.6277(8) Å, b = 9.8488(7) Å, c = 21.822(2) Å, = 97.945(2)°; (19) P2₁/c, a = 15.381(3) Å, b = 6.667(1) Å, c = 18.158(3) Å, = 94.838(4)°; (25) C2/c, a = 34.386(4) Å, b = 11.318(1) Å, c = 13.409(2) Å, = 110.044(2)°; (28) , a = 10.4487(8) Å, b = 11.5677(9) Å, c = 13.354(1) Å, = 71.042(1)°, = 87.344(1)°, = 65.839(1)°; (29) P2₁/c, a = 10.8138(5) Å, b = 16.4949(8) Å, c = 22.054(1) Å, = 96.087(1)°.     

Structural studies of N(4)-substituted thiosemicarbazones prepared from 4-formylantipyrine and a thiourea derived from 4-aminoantipyrine

Reaction of 4-formylantipyrine with N(4)-dimethylthiosemicarbazide and 3-piperidylthiosemicarbazide produces the N(4)-dimethylthiosemicarbazone (1), and the 3-piperidyl-thiosemicarbazone (2), respectively. Compound 1 is triclinic, space group P-1 with a = 6.329(1) Å, b = 11.699(1) Å, c = 11.943(1) Å, = 65.83(1)°, = 80.83(1)°, = 84.90(1)°, and V = 796.1(1) ų with Z = 2, for D _calc = 1.324 g/cm³. Compound 2 is triclinic, space group P-1 with a = 6.784(1) Å, b = 10.485(2) Å, c = 13.462(3) Å, = 102.05(2)°, = 98.61(2)°, = 101.32(2)°, and V = 899.8(5) ų with Z = 2, for D _calc = 1.319 g/cm³. Reaction of 4-aminoantipyrine with phenyl isothiocyanate produced N-antipyrine-N-phenylthiourea (3). Compound 3 is monoclinic, space group P2₁/n with a = 6.863(7) Å, b = 15.361(3) Å, c = 16.332(5) Å, = 90.35(6)°, and V = 1720.7(18) ų with Z = 4, for D _calc = 1.306 g/cm³. Compounds 1 and 2 have intermolecular hydrogen bonding between the carbonyl oxygen of the antipyrine moiety and the NH hydrogen of the thiosemicarbazone moiety. In 3 the two unique molecules are held together as a dimer by interactions of the two thiourea NH's and the antipyrine moiety's\break oxygen.     

Regiospecific ligand addition to the donor–acceptor compound Ru2(CO)6(bpcd): syntheses and X-ray diffraction structures of Ru2(CO)5L(bpcd) and Ru2(CO)5L[μ-C=C(PPh2)C(O)CH2C}(O)](μ2-PPh2) (where L = PMe3 and tBuNC)

Thermal and Me₃NO-assisted activation of the donor–acceptor complex Ru₂(CO)₆(bpcd) (1) [where bpcd = 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] with PMe₃ or ^tBuNC affords the mono-substituted complexes Ru₂(CO)₅L(bpcd), as a result of regiospecific ligand attack at the diphosphine-substituted ruthenium center. Solution NMR measurements (¹H and ³¹P) reveal that the PMe₃ derivative exists as a noninterconverting mixture of axial (3a) and equatorial (3e) isomers, with the only the equatorial isomer being observed for Ru₂(CO)₅(^tBuNC)(bpcd) (5). Near-UV irradiation of 1 in the presence of added ligand yields Ru₂(CO)₅L(bpcd), in addition to the known ₂-phosphido complex Ru²(CO)⁶ [-C=C(PPh₂)C(O)CH₂C(O)](₂-PPh₂) (2) and the corresponding phosphido-substituted complexes Ru²(CO)_5L[-{C =C(PPh₂)C(O)CH₂C}(O)]₂-PPh₂)[4 (L = PMe₃); 6 (L = ^tBuNC)]. As with compounds 3a, 3e, and 5, both 4 and 6 exhibit ligand attachment at the diphosphine-substituted ruthenium center. The molecular structures of 3e, 4, 5, and 6 were determined by X-ray crystallography. 3e, as the 1/2 C₆H₆ solvate, crystallizes in the monoclinic space group C2/c: a = 40.573(3) Å, b = 10.2663(9) Å, c = 18.347(1) Å, = 95.371(6)°, V = 7609(1) ų and Z = 8; 4, crystallizes in the monoclinic space group P2₁/n: a = 10.8241(8) Å, b = 18.074(1) Å, c = 19.194(1) Å, = 96.968(6)°, V = 3727.3(5) ų, and Z = 4; 5, as the 1/2CH₂Cl₂ solvate, crystallizes in the monoclinic space group C2/c: a = 40.955(3) Å, b = 9.7230(6) Å, c = 20.542(1) Å, = 106.596(5)°, V = 7839.2(9) ų, and Z = 8; 6, as the 1/2C₅H₁₂ solvate, crystallizes in the monoclinic space group P2₁/c: a = 21.773(2) Å, b = 10.907(3) Å, c = 18.744(4) Å, = 114.68(1)°, V = 4045(1) ų, and Z = 4. The site occupied by the PMe₃ and ^tBuNC ligands in these compounds is discussed relative to the steric size/electronic properties of the ancillary ligand and its interaction with the bpcd ligand.     

Influence of the spectator cation on the structure of anionic pyridine-2,6-dicarboxylato complexes of cobalt(II), nickel(II), and copper(II)

The structures of anionic pyridine-2,6-dicarboxylato (pdc^2–) complexes of cobalt, nickel, and copper have been studied. The stoichiometries and structures are very much dependent on whether KOH, Et₄NOH, or NaOH is used in the synthesis to deprotonate the H₂pdc ligand. Crystallographic results are: (1) K₂[Co(pdc)₂] · 7H₂O, orthorhombic, Pnna, Z = 4, a = 20.637(2)Å, b = 13.480(1)Å, c = 8.200(1)Å (2) K₂[Ni(pdc)₂] · 7H₂O, orthorhombic, Pnna, Z = 4, a = 20.648(1)Å, b = 13.375(1)Å, c = 8.2393(8)Å (3) [Co₂(H₂O)₅(pdc)₂] · 2H₂O, monoclinic, P2₁/c, Z = 4, a = 8.3880(6)Å, b = 27.384(2)Å, c = 9.6110(8)Å, = 98.271(6)° (4) [Ni(Hpdc)₂] · 3H₂O, monoclinic, P2₁/c, Z = 4, a = 13.679(1)Å, b = 10.0450(9)Å, c = 13.767(2)Å, = 115.184(7)° (5) Na₆[Co(H₂O)₆][Co(pdc)₂]₄ · 28H₂O, monoclinic, P2₁/n, Z = 2, a = 13.363(1)Å, b = 8.437(1)Å, c = 40.689(3)Å, = 91.288(5)° (6) Na[Ni(Hpdc)(pdc)] · 11.5H₂O, monoclinic, C2/m, Z = 4, a = 15.200(2)Å, b = 22.299(2)Å, c = 8.3596(7)Å, = 118.894(7)° (7) Na[Cu(Hpdc)(pdc)] · 3H₂O, monoclinic, P2₁/n, Z = 4, a = 9.516(4)Å, b = 14.917(6)Å, c = 12.247(5)Å, = 92.00(5)°. The potassium and sodium complexes have extensive K⁺—H₂O and Na⁺—H₂O networks. The fact the Et₄N⁺ ion does not appear in any of the complexes is likely due to the fact that it is incapable of forming the intricate cation—water and hydrogen-bonding networks observed in all of the other structures.     

Synthesis of a new dibenzo-14-crown-4 lariat ether and structure of its sodium perrhenate complex

A dibenzo-14-crown-4 ether with a novel monooxyacetone sidearm is prepared and its structure with sodium perrhenate is determined. The structure crystallizes in P2₁/c with cell dimensions: a = 8.107(2) Å, b = 28.138(3) Å, c = 10.293(2) Å, and = 104.173(9)°; giving a volume of 2276.6(7) ų. This structure is compared to other sodium complexes of dibenzo-14-crown-4 lariat ethers and is found to be the only one with intramolecular bonding between the sidearm and the cation. Possible reasons for this observation are discussed.     

X-ray crystal structures of twocis-Mo(CO)4{(Ph2PO)2P(O)R} (R=Me,MeO-p-C6H4) complexes with unusual Mo-PPh2-O-P(O)R-O-PPh2 chelate rings

The X-ray crystal structures of twocis-Mo(CO)₄{(Ph₂PO)₂P(O)R} (I:R=Me; II: R=C₆H₄-p-OMe) complexes are presented. Complex I crystallizes in the monoclinic space groupP2₁/n (a=11.566(1),b=10.045(2),c=25.959(4)Å;=97.64(1)°;V=2989.0 ų;Z=4). Complex II crystallizes in the triclinic space group P¯1 (a=8.868(2),b=11.552(2),c=16.818(3)Å,=78.32(1)°,=93.70(2)°, =86.59(2)°,V=1679.0 ų,Z=2). The coordination geometry of the molybdenum in each of these complexes is a slightly distorted octahedron. The six-membered chelate rings in these complexes have twist boat configurations with both ends flattened. The two rings differ in the degree of twisting in the boat and in the degree to which both ends of the boat are distorted from the ideal configurations. The twisting is greater in II, but the distortion is greater in I. Both appear to be due to the differing sizes of the substituent on the phosphonate phosphorus with larger substituents giving less twisting and flattening.     

Diphosphine ring expansion and π-bond reduction in the reaction between 1,2-bis(diphenylphosphino) cyclobutenedione (bpcbd) and Ru3(CO)10(MeCN)2: X-ray diffraction structures of Ru3(CO)10[2,3- bis(diphenylphosphino)succinic anhydride] and Ru2(CO)6(bma)

Replacement of the acetonitrile ligands in Ru₃(CO)₁₀(MeCN)₂ by the diphosphine ligand 1,2-bis(diphenylphosphino)cyclobutenedione (bpcbd) initially gives the unstable bpcbd-bridged cluster Ru₃(CO)₁₀(bpcbd) (1), followed by its subsequent transformation to the triruthenium cluster Ru₃(CO)₁₀(bma) (2). The decomposition of cluster 2 serves to produce the ruthenium compounds Ru₃(CO)₁₀[2,3-bis(diphenylphosphino)succinic anhydride] (3) and Ru₂(CO)₆(bma) (4). Compounds 2–4 provide the experimental evidence for the ring expansion of the cyclobutenedione ring via the formal insertion of an oxygen atom into the four-membered ring and hydrogen addition to the bond upon exposure to the atmosphere and/or moisture. Both 3 and 4 have been isolated and characterized in solution by IR and ³1P NMR spectroscopies, and the molecular structure of each product has been verified by X-ray crystallography. Ru₃(CO)₁₀[2,3-bis(diphenylphosphino)succinic anhydride] crystallizes, as the CH₂Cl₂ solvate, in the monoclinic space group P2₁/c, a = 12.178(2)Å, b = 15.988(2)Å, c = 22.472(3)Å, = 95.115(2)°, V = 4358(1)ų, Z = 4, and d_calc = 1.732 Mg/m³; R = 0.0344, R_w = 0.0931 for 5683 reflections with I > 2(I). The dinuclear compound Ru₂(CO)₆(bma) crystallizes in the triclinic space group P-1, a = 9.298(3)Å, b = 12.020(3)Å, c = 30.858(8)Å, = 81.774(5)°, = 89.276(5)°, = 83.545(4)°, V = 3391(1)ų, Z = 4, and d_calc = 1.730 Mg/m³; R = 0.0670, R_w = 0.1444 for 8766 reflections with I > 2a(I).     

Nonpreorganized neutral acyclic anion receptors: Structural investigations of N,N′-diphenyl-1, 3-benzenedisulfonamide and N,N′bis(4-t-butylphenyl)-1, 3-benzenedisulfonamide

The structure of N,N-diphenyl-1,3-benzenedisulfonamide (1) was determined by single crystal X-ray diffraction. It crystallizes in P2₁/n with cell dimensions: a = 11.8390(6) Å, b = 12.3950(10) Å, c = 12.1184(10) Å, = 94.388(6)°, and V = 1773.1(2) ų. Its di-t-butyl derivative, N,N-bis(4-t-butylphenyl)-1,3-benzenedisulfonamide (2), was prepared and structurally characterized as two solvated structures. Both crystallize in P with cell dimensions: 2 CF₃CH₂OH, a = 9.469(2) Å, b = 10.0039(18) Å, c = 16.385(3) Å, = 85.561(16)°, = 83.035(18)°, = 72.459(16), and V = 1467.7(5) ų; 2 ClCH₂CH₂Cl, a = 9.559(2) Å, b = 9.8125(12) Å, c = 17.100(6) Å, = 82.495(19)°, = 83.47(2)°, = 70.100(15), and V = 1491.1(6) ų. The structures exhibit hydrogen-bonding, and are evaluated in terms of preorganization for anion binding.     

Copper(II) complexes 1-phenylpropane-1,2-dione- and benzil bis(3-piperidylthiosemicarbazone): A structural study

The crystal and molecular structure of copper(II) complexes of benzil bis(3-piperidylthiosemicarbazone), [Cu(Bnzpip)] and 1-phenylpropane-1,2-dione bis(3-piperidylthiosemicarbazone), [Cu(Pmpip)] have been determined. [Cu(Bnzpip)] is monoclinic, space group P2₁/n with a = 13.9375(10) Å, b = 11.6621(4) Å, c = 16.4710(10) Å, = 100.667(2)°, and V = 2630.9(3) ų with Z = 4, for d _calc = 1.399 g/cm³. [Cu(Pmpip)] is also monoclinic, space group P2₁/n with a = 11.292(6) Å, b = 10.219(5) Å, c = 20.292(6) Å, = 101.50(3)°, and V = 2295(2) ų with Z = 4, for d _calc = 1.525 g/cm³. Both complexes involve N₂S₂ coordination, are relatively planar except for the phenyl rings and have similar bond distances and angles to copper(II) complexes of other 3-piperidylthiosemicarbazones.