Jean-Cyrille Hierso’s research while affiliated with French National Centre for Scientific Research and other places

... Then N-oxide formation was tested, as such reactivity is characteristic of aromatic amino-heterocycles. 8 In the presence of an excess of trifluoroacetic anhydride and H 2 O 2 , the oxidation of 17 led to the formation of two products in a 50/50 ratio. X-ray diffraction allowed those products to be assigned to the derivatives where the N-oxidation had occurred selectively at N1 (17-O1) and N2 (17-O2) with 35% and 32% isolated yields (Scheme 4). ...

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Molecular Engineering of 3-Arylated Tetrazo[1,2-b]indazoles: Divergent Synthesis and Structure-property Relationships

... The dimethylamino group in the side chain was then converted to a phosphine. The synthetic sequence furnished a prototype of hitherto unexplored ferrocenebased chiral sulfoxide phosphine ligands (14) that are structurally related to the widely used Josiphos diphosphines 55 and feature a sulfur stereocenter in addition to the ferrocene chiral plane and the stereogenic side chain. Moreover, a sequence of a base-promoted amino group exchange with diamine 15 and a reaction with isothiocyanate 16 provided simple entry to thiourea 17. ...

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Construction of sulfur stereocenters by asymmetric geminate recasting

... The deviations between calculated rate constants from Eq. (5) and experimental rate constants have been observed by many authors [41][42][43][44][45]. Necibi and co-workers, for example, have observed a linear correlation between the experimental rate constants (log k exp 1 ) and calculated rate constants (log k calcd 1 ) for reactions of benzoselenadiazolium cation 11 with the nitroalkyl anions 10a-c in methanol (log k exp 1 = − 0.88 + 1.14 log k calcd 1 (R 2 = 0.9875)) [45]. ...

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Electrophilicity, Mechanism and Structure-Reactivity Relationships of Cyclic Secondary Amines Addition to 2-Methoxy-3,5-dinitropyridine

... Suppose a catalyst possesses catalytic activity in both AB hydrolysis and methanolysis with only solvent change and is freely switchable, enabling the convenient application to various working conditions. For instance, Hierso et al. [21] reported that 7%-Ru@Fe 3 O 4 magnetic nanocatalysts exhibited excellent activity for AB hydrolysis and methanolysis at room temperature (298 K) with turnover frequencies (TOF) of 20 and 30 min − 1 , respectively. To our knowledge, this is the only reported bifunctional catalyst with high catalytic activity in both AB hydrolysis and methanolysis. ...

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Rattle-structured CuO/Co3O4@C microspheres, a potent bifunctional catalyst for hydrogen production from ammonia borane hydrolysis and methanolysis

... Thus, EEs could transmit the nuclear spin or electronic information between He and the cage shell, but the transmission is certainly influenced by He-roaming, as evidenced by numerous studies in which the transmission of interaction information between two coupled atomic nuclei occurs through intervening electrons as the through-bond vs through space pathways. 18,32,46,50,57 In particular, the dispersed EEs can enhance the internuclear spin-spin coupling interaction, 18,46 and thus, the He-stirred EEs dynamics inevitably play a unique role in achieving dynamic transmission of the coupling information. We further investigate how the dynamic EEs mediate the J-coupling (J HeC ) between the roaming He and cage shell C in (He, en)@C 60 F 60 . ...

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Helium roaming in excess electrons in C60F60 as dynamic quasi-Matryoshka dolls

... In this context, a vast number of Au(I)-catalyzed reactions bear much attention [20][21][22] because attractive aurophilic interaction between closed-shell d 10 Au(I) atoms facilitates the formation of polyaurated reaction intermediates. [23][24][25][26][27][28][29][30] As gold(I) complexes act as a superior Lewis acid to activate unsaturated p-systems, 31 coordination of a substrate to Au(I) followed by the attack of a nucleophile oen generates isolable organogold intermediates. They are generally believed to undergo a subsequent protodeauration process to output desired organic products and regenerate gold(I) catalytic species. ...

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Divergent catalytic behaviors of assembled organogold(i) clusters derived from enyne cyclization

... The synthesis of the ligand diphenyl(1-pyrenyl)phosphane (L) was reported earlier. 22,27 Cyclometalated complexes 1 and 2 were typically prepared by reaction of the corresponding pentamethylcyclopentadienyl metal dichloride dimer ([Cp*MCl 2 ] 2 ; M = Ir or Rh; Cp* = pentamethylcyclopentadienyl) with two equivalents of ligand L (Scheme 1, top) and four equivalents of sodium acetate, in methanol at room temperature for two hours. The cationic complexes containing an S-coordinated DMSO molecule, i.e. 1·DMSO and 2·DMSO, were also prepared by reaction of respectively 1 and 2 with 10 equivalents of DMSO and 1.1 equivalents of thallium hexafluorophosphate in dichloromethane overnight at room temperature (Scheme 1, bottom). ...

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Cyclometalated half-sandwich iridium(III) and rhodium(III) complexes as efficient agents against cancer stem-cell mammospheres

... We next achieved complexation of the polyaromatic phosphines 18 and 27 to coinage metals with gold(I) chloride and copper(I) chloride salts (Table 1 and Scheme 4). 23,24 For fluoranthenyl diphenylphosphines 18 and 27, the reaction with [(Me 2 S)AuCl] quantitatively led to complexes A and B that were characterized via 31 P NMR spectroscopy (202 MHz, CDCl 3 ), demonstrating singlets at 24.5 ppm and 30.5 ppm, respectively (Scheme 4; see also the XRD of B in Figure 1; the XRD for A is reported in the Supporting Information). The complexation of 18 and 27 with Cu(I)Cl quantitatively led to complexes C and D, respectively, which were obtained in 73% and 76% isolated yields after precipitation, and were characterized by 31 P NMR spectroscopy (202 MHz, CDCl 3 ), showing broad signals at -8.7 ppm and -6.4 ppm, respectively (see Scheme 4; the XRD for C, as a classical cubane structure, is reported in the Supporting Information). ...

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Aryl Triflates in Phosphorus-Directed Rhodium(III)-Catalyzed C–H Activation

... Transition metal nanoparticles find wide applications in various fields, such as microelectronics [1], optical devices [2], catalysis [3], drug delivery [4], as well as hydrogen storage [5]. Among them, metal nanoparticles (Ag, Au, Pd, etc.) have received considerable attention due to their excellent and durable activity as heterogeneous catalysts in numerous liquid-phase catalytic reactions [6][7][8]. ...

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Facile synthesis of Cu, Ag, and Ni ultrafine nanoparticles supported on 3D hydrogel beads for the rapid reduction of 4-nitrophenol

... Here we address these dual challenges, we provide a comprehensive solution that not only operates independently of transgenic expression but also offers precise control of spatial distances, akin to a 'molecular ruler'-a mechanism that enables the accurate measurement of distances between biomolecules. The integration of non-enzymatic and bio-orthogonal ligation chemistries with fluorogenic properties presents a promising solution to fulfill this critical need (10)(11)(12). To this end, we developed and validated a fluorogenic dual-substrate recognition probe. ...

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Detection of protein-protein interactions by bio-orthogonal fluorogenic proximity probes