28 research outputs found
Synthesis of Cyclopropanes via Organoiron Methodology: Preparation of \u3cem\u3erac\u3c/em\u3e-Dysibetaine Cpa
The cyclopropane containing betaine, rac-dysibetaine CPa, was prepared from (1-methoxycarbonylpentadienyl)-Fe(CO)2PPh3+ by nucleophilic addition of nitromethane anion followed by oxidatively induced reductive elimination
Synthesis of Some New Fluorinated Hexahydroquinoline and Acridinedione Derivatives in Trifluoroethanol
This article describes one-pot synthesis of new fluorinated hexahydroquinoline derivatives via unsymmetric Hantzsch reaction involving 5-trifluoromethyl-1,3-cyclohexanedione, aldehydes, acetoacetate ester, and ammonium acetate in trifluoroethanol (TFE). The reaction is simple and rapid with high yield
HostâGuest Complex of ÎČ-Cyclodextrin and Disulfide Form of 4-Aminothiophenol
An inclusion complex of ÎČ-cyclodextrin and 4-aminothiophenol was assembled by hydrophobic interaction of the host (ÎČ-cyclodextrin) and guest (4-aminothiophenol). The complex was isolated as crystalline solid and studied by single crystal X-ray diffraction method along with NMR and IR spectroscopy. Two cyclodextrin rings each containing one disulfide form of 4-aminothiophenol were found to pair up by hydrogen bonding of the outer rim -OH groups. The phenyl disulfide moiety of 4-aminophenyl disulfide molecule was found in the core of ÎČ-cyclodextrin, while the amino functional groups were positioned to the exterior of the cyclodextrin ring. Phenyl rings of the guest molecule from each partner of the paired cyclodextrin complex were found parallel to each other, indicating possible Ï-Ï stacking interaction between them
Crystal and molecular structure of bis(8-phenylmenthyl) 2-(2-methyl-5-oxo-3-cyclohexen-1-yl)propandioate, C\u3csub\u3e42\u3c/sub\u3eH\u3csub\u3e54\u3c/sub\u3eO\u3csub\u3e5\u3c/sub\u3eâą CH\u3csub\u3e3\u3c/sub\u3eCN
The X-ray crystal structure of the title compound, as crystallized from acetonitrile-water was determined. The relative stereochemistry of the cyclohexenone ring with respect to the 8-phenylmenthyl esters was determined. The title compound crystallizes in the noncentrosymmetric space group P21, with a=8.9850(10) Ă
, b=15.575(3) Ă
, c=14.478(2) Ă
, ÎČ=94.61(2)°, and D calc=1.118 g cmâ3 for Z=2
Double CarbonâHydrogen Activation of 2-Vinylpyridine: Synthesis of Tri- and Pentanuclear Clusters Containing the ÎŒ-NC\u3csub\u3e5\u3c/sub\u3eH\u3csub\u3e4\u3c/sub\u3eCHâC Ligand
Reactions of 2-vinylpyridine with the triruthenium complexes [Ru3(CO)12] and [Ru3(CO)10(ÎŒ-dppm)] leads to a previously unknown double carbonâhydrogen bond activation of the ÎČ-carbon of the vinyl group to afford the pentaruthenium and triruthenium complexes [Ru5(CO)14(ÎŒ4-C5H4CHâC)(ÎŒ-H)2] (1) and [Ru3Cl(CO)5(ÎŒ-CO)(ÎŒ-dppm)(ÎŒ3-NC5H4CHâC)(ÎŒ-H)] (2), respectively. Crystal structures reveal two different forms of bridging of the dimetalated 2-vinylpyridyl ligand, capping a square face in 1 and a triangular face in 2
Reactions of Rhenium and Manganese Carbonyl Complexes with 1,8-bis(diphenylphosphino)naphthalene: Ligand Chelation, CâH and CâP bond-cleavage Reactions
Reaction of [Re2(CO)8(MeCN)2] with 1,8-bis(diphenylphosphino)naphthalene (dppn) afforded three mono-rhenium complexes fac-[Re(CO)3(Îș1:η1-PPh2C10H6)(PPh2H)] (1), fac-[Re(CO)3{Îș1:Îș1:η1-(O)PPh2C10H6(O)PPh(C6H4)}] (2) and fac-[ReCl(CO)3(Îș2-PPh2C10H6PPh2)] (3). Compounds 1â3 are formed by ReâRe bond cleavage and PâC and CâH bond activation of the dppn ligand. Each of these three complexes have three CO groups arranged in facial fashion. Compound 1 contains a chelating cyclometalated diphenylnaphthylphosphine ligand and a terminally coordinated PPh2H ligand. Compound 2 consists of an orthometalated dppn-dioxide ligand coordinated in a Îș1:Îș1:η1-fashion via both the oxygen atoms and ortho-carbon atom of one of the phenyl rings. Compound 3 consists of an unchanged chelating dppn ligand and a terminal Cl ligand. Treatment of [Mn2(CO)8(MeCN)2] with a slight excess of dppn in refluxing toluene at 72 °C, gave the previously reported [Mn2(CO)8(ÎŒ-PPh2)2] (4), formed by cleavage of CâP bonds, and the new compound fac-[MnCl(CO)3(Îș2-PPh2C10H6PPh2)] (5), which has an unaltered chelating dppn and a terminal Cl ligand. In sharp contrast, reaction of [Mn2(CO)8(MeCN)2] with slight excess of dppn at room temperature yielded the dimanganese [Mn2(CO)9{Îș1-PPh2(C10H7)}] (6) in which the diphenylnaphthylphosphine ligand, formed by facile cleavage of one of the PâC bonds, is axially coordinated to one Mn atom. Compound 6 was also obtained from the reaction of [Mn2(CO)9(MeCN)] with dppn at room temperature. The XRD structures of complexes 1â3, 5, 6 are reported
X-ray Structure of \u3cem\u3emer\u3c/em\u3e-[Mo(CO)\u3csub\u3e3\u3c/sub\u3e(PPh\u3csub\u3e3\u3c/sub\u3e)(\u3cem\u3eÎș\u3c/em\u3e\u3csup\u3e2\u3c/sup\u3e-dppm)]
Treatment of [Mo(CO)3(NCMe)3] with bis(diphenylphosphino)methane (dppm) and triphenylphosphine (PPh3) at 50 °C afforded mer-[Mo(CO)3(PPh3)(Îș2-dppm)] (1) in 55% yield which has been characterized by single crystal X-ray diffraction studies and spectroscopic measurements. Compound 1 crystallizes in the triclinic space group Pâ1 with a = 10.3449(6), b = 11.1570(6), c = 17.8961(10) Ă
, ÎČ = 80.8400(10)°, Z = 2 and V = 1959.8(2) Ă
3
Reactivity of phenyldi(2-thienyl)phosphine towards Group 7 Metal Carbonyls: Carbonâphosphorus Bond Activation
Addition of phenyldi(2-thienyl)phosphine (PPhTh2) to [Re2(CO)10ân(NCMe)n] (n = 1, 2) affords the substitution products [Re2(CO)10ân(PhPTh2)n] (1, 2) together with small amounts of fac-[ClRe(CO)3(PPhTh2)2] (3) (n = 2). Reaction of [Re2(CO)10] with PPhTh2in refluxing xylene affords a mixture which includes 2, [Re2(CO)7(PPhTh2)(ÎŒ-PPhTh)(ÎŒ-H)] (4), [Re2(CO)7(PPhTh2)(ÎŒ-PPhTh)(ÎŒ-η1,Îș1(S)-C4H3S)] (5) and mer-[HRe(CO)3(PPhTh2)2] (6). Phosphido-bridged 4 and 5 are formed by the carbonâphosphorus bond cleavage of the coordinated PPhTh2 ligand, the cleaved thienyl group being retained in the latter. Reaction of [Mn2(CO)10] with PPhTh2 in refluxing toluene affords [Mn2(CO)9(PPhTh2)] (7) and the carbonâphosphorus bond cleavage products [Mn2(CO)6(ÎŒ-PPhTh)(ÎŒ-η1,η5-C4H3S)] (8) and [Mn2(CO)5(PPhTh2)(ÎŒ-PPhTh)(ÎŒ-η1,η5-C4H3S)] (9). Both 8 and 9 contain a bridging thienyl ligand which is bonded to one manganese atom in a η5-fashion
2,9-Bis(5-sulfanylidene-4,5-dihydro-1,3,4-oxadiazol-2-yl)-1,10-phenanthroline dimethyl sulfoxide disolvate
In the title compound, C16H8N6O2S2·2C2H6OS, the phenanthroline molecule resides on a twofold axis, and the asymmetric unit also contains a slightly disordered [occupancy ratio for S atom of 0.95â
(3):0.047â
(3)] molecule of dimethyl sulfoxide. The O atoms of the solvent molecule accept hydrogen bonds from the NâH groups of the five-membered 2,3-dihydro-1,3,4-oxadiazole-2-thione ring. This ring is nearly coplanar with the phenanthroline ring, with a dihedral angle between their least-squares planes of 8.86â
(6)°. In the crystal, the molecules are linked by CâH...O interactions
Coordination Nature of 4-Mercaptoaniline to Sn(II) Ion: Formation of a One Dimensional Coordination Polymer and Its Decomposition to a Mono Nuclear Sn(IV) Complex
The coordination of the bifunctional ligand 4-mercaptoaniline with aqueo us tin(II) metal ion was studied. A coordination polymer was synthesized when an aqueous solution of SnCl2 was treated with 4-MA. The crystalline material is stable under atmospheric conditions retaining its oxidation state. However, when submerged in a solution saturated with oxygen, the compound oxidizes to a mononuclear tin(IV) complex. Both the compounds were characterized by single crystal X-ray diffraction studies. Although the structure of the tin(IV) complex was previously reported, crystal structure of this compound was redetermined