25360-32-1Relevant articles and documents
Structure-Based Design, Synthesis and Biological Evaluation of Bis-Tetrahydropyran Furan Acetogenin Mimics Targeting the Trypanosomatid F1 Component of ATP Synthase
Zacharova, Marija K.,Tulloch, Lindsay B.,Gould, Eoin R.,Fraser, Andrew L.,King, Elizabeth F.,Menzies, Stefanie K.,Smith, Terry K.,Florence, Gordon J.
supporting information, p. 5434 - 5440 (2019/06/10)
The protozoan parasites Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. are responsible for the severely debilitating neglected Tropical diseases of African sleeping sickness, Chagas disease and leishmaniasis, respectively. As part of our ongoing programme exploring the potential of simplified analogues of the acetogenin chamuvarinin we identified the T. brucei FoF1-ATP synthase as a target of our earlier triazole analogue series. Using computational docking studies, we hypothesised that the central triazole heterocyclic spacer could be substituted for a central 2,5-substituted furan moiety, thus diversifying the chemical framework for the generation of compounds with greater potency and/or selectivity. Here we report the design, docking, synthesis and biological evaluation of new series of trypanocidal compounds and demonstrate their on-target inhibitory effects. Furthermore, the synthesis of furans by the modular coupling of alkyne- and aldehyde-THPs to bis-THP 1,4-alkyne diols followed by ruthenium/xantphos-catalysed heterocyclisation described here represents the most complex use of this method of heterocyclisation to date.
Insight into the mechanism of decarbonylation of methanol by ruthenium complexes; a deuterium labelling study
Lorusso, Patrizia,Eastham, Graham R.,Cole-Hamilton, David J.
, p. 9411 - 9417 (2018/07/29)
In the reaction of [RuHClP3] (P = PPh3) with NaOMe in methanol, the product is [RuH2(CO)P3]. Short reaction times show that the final product is formed through [RuH4P3] as the major interme
Ring-expanded N-heterocyclic carbene complexes of ruthenium
Armstrong, Robert,Ecott, Christopher,Mas-Marza, Elena,Page, Mkhael J.,Mahon, Mary F.,Whittlesey, Michael K.
, p. 991 - 997 (2010/04/25)
The six-membered N-heterocyclic carbene l,3-bis(2,4,6-trimethylphenyl)-3,4, 5,6-tetrahydropyrimidin2-ylidene (6-Mes) reacts with Ru(PPh3) 3(CO)HF to afford Ru(6-Mes)(PPh3)(CO)HF (1), which is converted to the five-coordinate C-H activated carbene complex Ru(6-Mes)'(PPh3)(CO)H (2) upon treatment with Et3SiH. The hydride chloride precursor Ru(PPh3)3(CO)HCl affords a mixture of products with 6-Mes, but reacts cleanly with 1,3-bis(isopropyl)-3,4, 5,6-tetrahydropyrimidin-2-ylidene (6-1Pr) to give the six-coordinate activated complex Ru(6-1Pr)'(PPh3)2(CO)H (3a), in which the hydride is trans to the methylene arm of the activated NHC. This complex isomerizes in solution with ΔH# and Delta;S# values of 98.2 ± 4.6 kJ mol-1 and 15.5 ± 14.5Jmol -1 K-1.The major product from the isomerization, 3b, in which the hydride ligand is trans to carbene, can be made directly by reaction of 6-1Pr with Ru(PPh3)3(CO)H2.
A new oxidative addition of ruthenium(O) into an aryl halide bond and subsequent intermolecular C-H insertion
Grounds, Helen,Anderson, James C.,Hayter, Barry,Blake, Alexander J.
, p. 5289 - 5292 (2010/01/29)
Summary: An unprecedented oxidative insertion of the activated ruthenium complex Quot;Ru(CO)(PPh3)2" into aryl halide bonds enables a novel preparation of stable five-coordinate 16-electron d(6) o-aryl-Ru(II) complex Ru(CO)(p-C6
Catalytic hydrodefluorination of aromatic fluorocarbons by ruthenium N-heterocyclic carbene complexes
Reade, Steven P.,Mahon, Mary F.,Whittlesey, Michael K.
, p. 1847 - 1861 (2009/08/07)
The catalytic hydrodefluorination (HDF) of hexafluorobenzene, pentafluorobenzene, and pen- tafluoropyridine with alkylsilanes is catalyzed by the ruthenium N-heterocyclic carbene (NHC) complexes Ru(NHC)(PPh 3)2(CO)H2 (NHC = SIMes (1,3-bis(2,4,6-trimethylphenyl) imidazolin-2-ylidene) 13, SIPr (1,3- bis(2,6-diisopropylphenyl)imidazolin-2- ylidene) 14, IPr (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) 15, IMes (1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) 16). Catalytic activity follows the order 15 > 13 > 16 > 14, with 15 able to catalyze the HDF of C6F5H with Et3SiH with a turnover number of up to 200 and a turnover frequency of up to 0.86 h-1. The catalytic reactions reveal (i) a novel selectivity for substitution at the 2-position in C6F5H and C5F5N, (ii) formation of deuterated fluoroarene products when reactions are performed in C 6D6, or C6D5CD3, and (iii) a first-order dependence on [fluoroarene] and zero-order relationship with respect to [R3SiH]. Mechanisms are proposed for HDF of C 6F6 and C6F5H, the principal difference being that the latter occurs by initial C-H rather than C-F activation.
Ruthenium induced C-N bond activation of an N-heterocyclic carbene: Isolation of C- and N-bound tautomers
Burling, Suzanne,Mahon, Mary F.,Powell, Rachael E.,Whittlesey, Michael K.,Williams, Jonathan M. J.
, p. 13702 - 13703 (2007/10/03)
C-N bond activation of the N-heterocyclic carbene 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene occurs with Ru(PPh3)3(CO)HCl to give the C-2 bound 1-isopropyl-4,5-dimethylimidazol-2-ylidene complex Ru(C-IiPrHMe2/sub
Multifunctional ruthenium catalysts: A novel borohydride-stabilized polyhydride complex containing the basic, chelating diphosphine 1,4-bis(dicyclohexylphosphino)butane and its application to hydrogenation and Murai catalysis
Drouin, Samantha D.,Amoroso, Dino,Yap, Glenn P.A.,Fogg, Deryn E.
, p. 1042 - 1049 (2008/10/08)
[RuCl2(dcypb)(CO)]2 2 (dcypb = 1,4-bis(dicyclohexylphosphino)butane) was prepared in high yield via phosphine exchange between dcypb and RuCl2(CO)PPh3)2(DMF) (1). Reaction of 2 with 8 equiv of KBHsBu3 affords [fac-RuH3(CO)(dcypb)]- (3), stabilized by interactions with a K+ counterion and an intact KBHsBu3 molecule in the third coordination sphere. Substantial ion pairing accounts for the stability and high hydrocarbon solubility of 3. Complex 3 effects reduction of benzophenone under unprecedentedly mild conditions, at 1 atm of H2 in refluxing 2-propanol. It is also active for ortho functionalization of benzophenone under 20 atm of ethylene. Stoichiometric experiments reveal facile formation of orthometalated RuH(CO)[OC(C6H4)(Ph)](dcypb) (5), an intermediate proposed in both types of catalysis. The catalytic activity of isolated 5 supports this hypothesis in the case of hydrogenation but not of Murai catalysis. The X-ray crystal structures of 3 and 5 are reported.
Catalytic addition of ferrocenyl ketones to olefins with the aid of Ru(H)2(CO)(PPh3)3
Du, Hongguang,Liu, Qun,Shi, Shujian,Zhang, Shiwei
, p. 127 - 131 (2007/10/03)
The catalytic addition reactions of ferrocenyl ketones with terminal olefins in the presence of Ru(H)2(CO)(PPh3)3 as catalyst have been studied. Benzoylferrocene reacts with triethoxyvinylsilane, styrene and vinylferrocene, respectively, to give 1:1 coupling products I-III in high yields. C-H bond cleavage takes place at the carbon atom of the benzene ring at the ortho position of the carbonyl group and C-C bond formation takes place at the terminal carbon atom of the olefins. 2-Furoylferrocene reacts with vinylferrocene to give a 1:1 coupling product IV and the C-H bond cleavage takes place at the carbon atom of the furan ring at the ortho position of the carbonyl group and the C-C bond formation takes place at the terminal carbon atom of vinylferrocene. The new products I-IV have been characterized by elemental analysis, 1H-NMR and MS. The X-ray crystal structure of IV has been determined.
Synthesis, spectral and electrochemical studies of ruthenium(II)/(III) complexes of alicyclic β-ketamines
Prasanna,Srinivasan,Rajagopal,Athappan
, p. 426 - 429 (2007/10/03)
A series of ruthenium(II)/(III) complexes of alicyclic β-ketamines derived from 2-formylcyclohexanone and 4-X-substituted anilines, HFCA-X (where H is an ionisable enolic hydrogen and X = H, Cl, Br, OMe and NO2), have been prepared and characterized by spectroscopic techniques. The IR spectral data suggest the coordination of enolic oxygen and imino nitrogen to ruthenium. Ruthenium(II) complexes are diamagnetic (low spin d6, S = 0) and in solutions show intense MLCT transition. Their redox behaviours have been studied by cyclic voltammetry. The solid state low temperature ESR spectra of Ru(III) complexes show a low spin symmetry.
Proton transfer in aminocyclopentadienyl ruthenium hydride complexes
Ayllon, José A.,Sayers, Stephen F.,Sabo-Etienne, Sylviane,Donnadieu, Bruno,Chaudret, Bruno,Clot, Eric
, p. 3981 - 3990 (2008/10/08)
A new ruthenium hydride complex of the aminocyclopentadienyl ligand (Cp-N)RuH(PPh3)2 (Cp-N = C5H4CH2CH2NMe2, 1) has been prepared and characterized by X-ray diffraction. Protonation of 1 with excess HPF6 leads to the dicationic derivative [(Cp-NH)RuH2(PPh3)2]-(PF6) 2 (2), in which both the metal and the amino substituent have been protonated. Addition of 1 equiv of HBF4·Et2O to 1 leads to the complex [(Cp-N)Ru(PPh3)2](BF4) (3), containing a chelating amino cyclopentadienyl ligand after elimination of H2. However, using (HNEt3)-(BPh4) or (HPBu3)(BPh4) as protonating agent, it is possible to form [(Cp-NH)RuH(PPh3)2]-(BPh4) (4), which was isolated as yellow crystals of 4·H2O upon addition of undistilled methanol and characterized by X-ray crystallographic analysis. A fluxional process exchanging the ammonium proton and the hydride without changing the thermodynamic state of the system could be established by 1H NMR, and activation energies of 11 kcal·mol-1 were calculated for 4·H2O and the product resulting from in situ addition Of [HNEt3][BPh4] to 1, whereas an activation energy of 10.1 kcal·mol-1 was found for the product resulting from in situ addition of [HPBu3][BPh4] to 1. A density functional study (B3PW91) was carried out, and the dihydrogen bond in the model system for 4 was calculated to be 1.545 A?, in excellent agreement with T1 measurements (1.52 A?). The proposed mechanism for the fluxional process does not involve a proton transfer within the dihydrogen bond.
