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Silver-Telluride 2D organometallic nanofibers using diphenyl ditelluride (DPDT) as a precursor were synthesized. The synthesis was carried out by reacting DPDT with AgNO3 in acetonitrile at room temperature (RT) under an inert atmosphere. The resulting material was fully characterized using various techniques, including UV-VIS-NIR spectroscopy, steady-state and excited-state fluorescent spectroscopy, IR-FTIR-ATR spectroscopy, HR ESI MS spectrometry, high-resolution transmission electron microscopy (HRTEM), BF-STEM or HAADF-STEM, and confocal fluorescence microscopy images and conductivity measurements. Initially, the nanofibers were almost non-emissive. However, a remarkable modification was observed after treating the nanofibers with oleylamine under ultrasound treatment. This methodology induced an aggregation emission effect (AIE) in the solution and in the solid state, resulting in the formation of a highly red emissive fluorescent nanomaterial. This research provides valuable insights for developing new fluorescent materials with potential applications in various optical fields. Initially, the nanofibers were almost non-emissive. However, we observed a remarkable modification after treating the nanofibers with oleylamine under ultrasound treatment. This treatment induced an aggregation emissive effect (AIE) in the solution and solid state, resulting in the formation of a highly red emissive fluorescent material. Overall, our findings demonstrate the successful synthesis of 2D Silver-Telluride 2D organometallic nanofibers and the induction of AIE in the resulting material through oleylamine treatment. This research provides valuable insights for developing new fluorescent materials with potential applications in various fields.

Recently, selenium and tellurium atoms have been incorporated in various fluorophores such as rhodamine, cyanine, fluorescein, BODIPY, coumarin, and BOPHY for the detection and quantification of different analytes of biochemical and environmental interest by fluorescence measurements. The relevance of the insertion of chalcogen atoms in fluorescent compounds refers to their excellent redox characteristics, conferring unique properties to the resulting compounds, as analytical/biochemical probes. Additionally, selenium plays pivotal roles in biochemical events interacting selectively with endogenous sulfur-based biomolecules. About tellurium, there are only rare reports of its occurrence in certain fungi when exposed to tellurium-rich environments. Besides that, contrary to certain comments, generically, tellurium (and many organic tellurides) present low or no toxicity. This chapter provides a summary of all reported organic chalcogenated (Se and Te) fluorescent sensors, focusing on those containing selenium or tellurium in their structure, used in the detection of important analytes from a biological and environmental point of view, including metallic ions, reactive oxygen species (ROS), reactive nitrogen species (RNS), and biothiols.

Combined computational–experimental study to elucidate the mechanism of HTIB-promoted ring expansion reaction of bicyclic heterocycles bearing an exocyclic double bond.

Background: The most current reported methods of chalcogen insertion into BODIPY’s nuclei are based on nucleophilic substitution reactions of halogenated derivatives, metal-catalyzed cross-coupling reactions, or assistance by radical mechanisms. Recent reports describe Oxidative Nucleophilic Hydrogen Substitution (ONHS) reactions involving the functionalization of BODIPY nuclei by thiols, but the generalities of the strategy for other chalcogens was not yet demonstrated. Herein we report our contribution on the selenium-functionalization of BODIPY by ONHS in high yield. Objective: Aryl-Se-functionalization of 2,6-brominated BODIPY’s nuclei by ONHS reaction. Method: The procedure consists of a direct reaction of 2,6-brominated BODIPYs with in situ generated PhSeH in THF, at room temperature, under a nitrogen atmosphere. The corresponding products were isolated and purified by conventional flash column chromatography. Full structure characterization was performed by 1H, 13C, 19F, and 77Se NMR and DFT calculation. Results: Densely functionalized 2,6-dibrominated/3,5-diseleno-BODIPYs were obtained as corresponding products, leading to versatile molecular scaffolds. Their structural features were contrary to those initially expected by the original experimental applied conditions. A mechanistic investigation was performed to conclude that ONHS reaction is governing the transformation, thereby damaging the nucleophilic substitution of the halogen atoms. Conclusion: To sum up, new densely functionalized BODIPY derivatives were synthesized by a highly selective, simple, fast, metal-free, and efficient insertion of PhSe- residues into the 3,5-positions, governed by an Oxidative Nucleophilic Hydrogen Substitution (ONHS) reaction in high yields. It was observed that the presence of halogen (Br) into the 2,6-positions of the BODIPY core is mandatory for the ONHS reaction, which is completely inert when the 2,6-hydrogenated analogues are used in the same experimental conditions.

Made available in DSpace on 2021-06-25T10:44:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-30 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). The persistent inflammation is being mainly attributed to local oxidative stress and inflammasome activation implicated in the ensuing demyelination and axonal damage. Since new control measures remain necessary, we evaluated the preventive and therapeutic potential of a beta-selenium-lactic acid derivative (LAD-βSe), which is a source of organic selenium under development, to control experimental autoimmune encephalomyelitis (EAE) that is an animal model for MS. Two EAE murine models: C57BL/6 and SJL/J immunized with myelin oligodendrocyte glycoprotein and proteolipid protein, respectively, and a model of neurodegeneration induced by LPS in male C57BL/6 mice were used. The preventive potential of LAD-βSe was initially tested in C57BL/6 mice, the chronic MS model, by three different protocols that were started 14 days before or 1 or 7 days after EAE induction and were extended until the acute disease phase. These three procedures were denominated preventive therapy −14 days, 1 day, and 7 days, respectively. LAD-βSe administration significantly controlled clinical EAE development without triggering overt hepatic and renal dysfunction. In addition of a tolerogenic profile in dendritic cells from the mesenteric lymph nodes, LAD-βSe also downregulated cell amount, activation status of macrophages and microglia, NLRP3 (NOD-like receptors) inflammasome activation and other pro-inflammatory parameters in the CNS. The high Se levels found in the CNS suggested that the product crossed the blood-brain barrier having a possible local effect. The hypothesis that LAD-βSe was acting locally was then confirmed by using the LPS-induced neurodegeneration model that also displayed Se accumulation and downmodulation of pro-inflammatory parameters in the CNS. Remarkably, therapy with LAD-βSe soon after the first remitting episode in SJL/J mice, also significantly downmodulated local inflammation and clinical disease severity. This study indicates that LAD-βSe, and possibly other derivatives containing Se, are able to reach the CNS and have the potential to be used as preventive and therapeutic measures in distinct clinical forms of MS. Department of Chemical and Biological Sciences Institute of Biosciences São Paulo State University (UNESP) Department of Structural and Functional Biology São Paulo State University (UNESP) Institute of Biosciences Veterinary Clinical Laboratory School of Veterinary Medicine and Animal Science (FMVZ) São Paulo State University (UNESP) Department of Research and Development Biorigin Company LabSSeTe Department of Fundamental Chemistry Institute of Chemistry University of São Paulo (USP) Department of Chemical and Biological Sciences Institute of Biosciences São Paulo State University (UNESP) Department of Structural and Functional Biology São Paulo State University (UNESP) Institute of Biosciences Veterinary Clinical Laboratory School of Veterinary Medicine and Animal Science (FMVZ) São Paulo State University (UNESP) FAPESP: 2016/23318-8

This study describes a single step, high yield and purity, ecofriendly and scalable procedure to prepare a selenium derivative (diethyl selenodiglycolate). Diethyl selenodiglycolate rapidly reduces hypochlorous acid (HOCl, second-order rate constant of 7 × 107 M−1 s−1) to generate its corresponding selenoxide. In activated HL-60 cells, diethyl selenodiglycolate selectively reacted with HOCl (half maximal inhibitory concentration (IC50) = 23.07 µM) but not with superoxide anion radical or hydrogen peroxide without any cytotoxicity. These results show that this synthetically simple selenide reacts in a very efficient and specific way with the harmful pro-oxidant HOCl being a promising compound to be applied in oxidative inflammatory-related conditions.

A new fluorescent probe based on Tellurium-Rhodamine (TR) was designed, synthetized and fully characterized by 1H NMR, 13C NMR, 125Te NMR, HRMS, IR and single crystal X-ray diffraction. A mechanism of Hg2+ detection, based on the oxidation of tellurium by Hg2+ was observed and fully understood. The new monomer chemosensor TR shows a high fluorescent quantum yield Φ = 0.41, excellent selectivity and good sensibility towards Hg2+, with a limit of detection of 2.95 μmol/L.

A new chemosensor based on tellurium-rhodamine B (TRB) for the fast and selective detection of Hg2+ in aqueous medium was designed and synthetized in only two steps from a symmetrical organic telluride and rhodamine B. The structure of TRB was determined by RMN, HRMS and IR and its photophysical properties were determined in MeCN/H2O 75:25 v/v. TRB is able to detect Hg2+ in solutions diluted until 1.71 μmol/L and containing until 75% of water in it. In the presence of Hg2+, TRB presents an intense pink color with maximum absorption in 558 nm (log e = 4.93) and a strong fluorescence emission with maximum intensity in 582 nm (Φ = 0.17). The detection of Hg2+ by TRB occurs by the oxidation of the tellurium promoted by Hg2+, where a redox mechanism was proposed. Even the detection of Hg2+ occurring by the oxidation of tellurium, TRB presented a high selectivity for Hg2+, even when several ROS (H2O2, KNO2, NaOCl, NaONOO e KO2) were submitted to the screening.

FAPESP CNPq CAPES NAP-CatSinQ Hypervalent tellurium compounds (telluranes) are promising therapeutical agents with negligible toxicities for some diseases in animal models. The C-Te bond of organotellurium compounds is commonly considered unstable, disfavoring their applicability in biological studies. In this study, the stability of a set of telluranes composed of an inorganic derivative and noncharged and charged organic derivatives was monitored in aqueous media with H-1, C-13, and Te-125 NMR spectroscopy and high-resolution mass spectrometry. Organic telluranes were found to be remarkably resistant and stable to hydrolysis, whereas the inorganic tellurane AS101 is totally converted to the hydrolysis product, trichlorooxytellurate, [TeOCl3](-), which was also observed in the hydrolysis of TeCl4. The noteworthy stability of organotelluranes in aqueous media makes them prone to further structure-activity relationship studies and to be considered for broad biological investigations. Univ São Paulo, Inst Quim, BR-05508020 São Paulo, SP, Brazil Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre, SP, Brazil Univ Fed São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-04021001 Diadema, SP, Brazil Univ Fed São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, BR-04021001 Diadema, SP, Brazil FAPESP: 2014/15962-5 FAPESP: 2015/08539-1 CNPq: 487012/2012-7 Web of Science

Tuning laccase/TEMPO-catalyzed aerobic oxidation of secondary propargylic alcohols in aqueous media was accomplished in order to efficiently synthesize ynones. This study led to the formulation of an effective and sustainable catalytic method for the preparation of mono- and bis-substituted ynones compared with traditional oxidative methods.

A novel reversible fluorescent probe for Pd2+ based on a rhodamine-containing selenide (Rh–Se) was designed, synthesized and fully characterized. The probe Rh–Se showed a high selectivity and sensitivity with a detection limit of 32 nM for Pd2+ ions. The formation of a complex Rh–Se/Pd2+ was confirmed by HRMS. DFT calculations revealed that the proposed square planar geometry is the most stable form of the metallic complex Rh–Se/Pd2+. The probe Rh–Se showed to have high potential for the detection of residual Pd2+ in synthetic cross-coupling products and simulated pharmaceutical Pd2+- contaminated products.

Metals capped with organochalcogenides have attracted considerable interest due to their practical applications, which include catalysis, sensing, and biosensing, due to their optical, magnetic, electrochemical, adhesive, lubrication, and antibacterial properties. There are numerous reports of metals capped with organothiol molecules; however, there are few studies on metals capped with organoselenium or organotellurium. Thus, there is a gap to be filled regarding the properties of organochalcogenide systems which can be improved by replacing sulfur with selenium or tellurium. In the last decade, there has been significant development in the synthesis of selenium and tellurium compounds; however, it is difficult to find commercial applications of these compounds because there are few studies showing the feasibility of their synthesis and their advantages compared to organothiol compounds. Stability against oxidation by molecular oxygen under ambient conditions is one of the properties which can be improved by choosing the correct organochalcogenide; this can confer important advantages for many more suitable applications. This paper reports the successful synthesis and characterization of gold nanoparticles functionalized with organochalcogenide molecules (dibutyl-disulfide, dibutyl-diselenide and dibutyl-ditelluride) and evaluates the oxidation stability of the organochalcogenides. Spherical gold nanoparticles with diameters of 24 nm were capped with organochalcogenides and were investigated using X-ray photoelectron spectroscopy (XPS) to show the improved stability of organoselenium compared with organothiol and organotellurium. The results suggest that the organoselenium is a promising candidate to replace organothiol because of its enhanced stability towards oxidation by molecular oxygen under ambient conditions and its slow oxidation rate. The observed difference in the oxidation processes, as discussed, is also in agreement with theoretical calculations.

The nanoscale pH gradients from a charged membrane interface to the bulk solution, determine fundamental properties of chemical and biological systems. We estimated the proton distribution on micelle surfaces experimentally measuring the apparent pKa of a weak acid linked at varying distances to a micelle anchoring moiety and relating these values to the electrical potential at the micellar surface. The pH probes consisted of benzoic acid connected to chains with variable number (1–5) oxyethylene (−OCH2CH2–) units. The methylene of the terminal oxyethylene was connected to a quaternary nitrogen containing a long hydrocarbon chain. We calculated the apparent pKa (pKap) of the benzoic acid derivatives with surfactant micelles by UV spectroscopy. The difference between the pKa in solution and the pKap in micelles (ΔpK) of all probes was very similar with negatively charged sodium dodecyl sulphate (SDS) or zwitterionic N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS) micelles, indicating that the dissociation of the substituted benzoates occurred at the micellar interface in both SDS and HPS. In contrast, the ΔpK of the probes decreased as a function of the benzoate's distance to the micelle interface in hexadecyltrimethylammonium chloride (CTAC) micelles, The variation of ΔpK with distance, from the CTAC micellar interface to bulk solution, was quantitatively correlated to H+ distribution from the interface. The experimental results coincided with independently calculated Poisson Boltzmann H+ distribution. These results demonstrate that that it is possible to experimentally map H+ gradients from a charged interface.

Long-term preservation of the properties of gold nanoparticles in both solution and the dry powder form can be difficult. We have overcome this challenge by using organotellurium derivatives as both reducing agents and stabilizers in the synthesis of gold nanoparticles. This new synthetic protocol takes advantage of the photochemical and oxidative properties of diphenyl ditelluride (Ph2Te2), which, so far, have never been exploited in the synthesis of gold nanoparticles. The Au/Te core/shell (inorganic/organic) hybrid nanomaterial can be obtained in a one-step reaction, using only Ph2Te2 and HAuCl4. By modifying the reaction conditions, different resonance conditions of the gold core are achieved due to the formation of external shells with different thicknesses. The organotellurium shell can be easily removed by resuspension of the nanoparticles in environmentally friendly solvents, such as water or ethanol, making the Au core available for subsequent applications. A mechanism for the formation of core/shell nanoparticles has also been discussed.

A series of optically active helical copolymers of phenylacetylenes are prepared by the rhodium-catalyzed copolymerization of the imidazolidinone-linked, catalytically active achiral phenylacetylenes and catalytically inactive chiral phenylacetylenes. The obtained chiral/achiral copolymers exhibit an induced circular dichroism in the UV-vis regions of the copolymer backbones resulting from a preferred-handed helical conformation biased by the chiral imidazolidinone units incorporated in the copolymers. The copolymers are found to catalyze the asymmetric Diels-Alder reaction and produce the products with a moderate enantioselectivity in spite of the fact that the catalytically active units of the copolymers are achiral, indicating that the observed enantioselectivity totally originates from the helical chirality dynamically induced by the optically active, but catalytically inactive imidazolidinone units incorporated in the copolymers.

Antimicrobial peptides (AMPs) work as a primary defense against pathogenic microorganisms. BP100, (KKLFKKILKYL-NH2), a rationally designed short, highly cationic AMP, acts against many bacteria, displaying low toxicity to eukaryotic cells. Previously we found that its mechanism of action depends on membrane surface charge and on peptide-to-lipid ratio. Here we present the synthesis of two BP100 analogs: BP100‑alanyl‑hexadecyl‑1‑amine (BP100-Ala-NH-C16H33) and cyclo(1‑4)‑ d ‑Cys1, Ile2, Leu3, Cys4-BP100 (Cyclo(1‑4)‑cILC-BP100). We examined their binding to large unilamellar vesicles (LUV), conformational and functional properties, and compared with those of BP100. The analogs bound to membranes with higher affinity and a lesser dependence on electrostatic forces than BP100. In the presence of LUV, BP100 and BP100-Ala-NH-C16H33 acquired α-helical conformation, while Cyclo(1‑4)‑cILC-BP100) was partly α-helical and partly β-turn. Taking in conjunction: 1. particle sizes and zeta potential, 2. effects on lipid flip-flop, 3. leakage of LUVs internal contents, and 4. optical microscopy of giant unilamellar vesicles, we concluded that at high concentrations, all three peptides acted by a carpet mechanism, while at low concentrations the peptides acted by disorganizing the lipid bilayer, probably causing membrane thinning. The higher activity and lesser membrane surface charge dependence of the analogs was probably due to their greater hydrophobicity. The MIC values of both analogs towards Gram-positive and Gram-negative bacteria were similar to those of BP100 but both analogues were more hemolytic. Confocal microscopy showed Gram-positive B. subtilis killing with concomitant extensive membrane damage suggestive of lipid clustering, or peptide-lipid aggregation. These results were in agreement with those found in model membranes.

A new process to produce magnetite partially coated with strawberry-like gold nanoparticles in aqueous media is reported. The fast response to magnetic fields and optical properties of gold nanoparticle-based colloidal systems are the two main advantages of this new Fe@Au nanomaterial. These advantages allow for the use of this new colloidal nanomaterial for various purposes in proteomics and biomedicine, as proteins can bind to the surface, and the surface can also be functionalized. As proof-of-concept, the new Fe@Au nanoparticles have been assessed in biomarker discovery as a tool for pre-concentration and separation of proteins from complex proteomes. To this end, sera from healthy people were compared with sera from patients diagnosed with multiple myeloma. The application of this new Fe@Au nanomaterial combined with mass spectrometry has allowed for the identification of 53 proteins, and it has also shown that the heat shock protein HSP75 and the plasma protease C1 inhibitor are potential biomarkers for diagnostics and control of multiple myeloma progression.

This account covers the synthesis and biological applications of organoseleno- and organotelluro-based molecular dyes. The most relevant applications for photodynamic therapy (PDT), fluorescent probes for the detection of endogenous reactive oxygen species (ROS), natural bioreductors like glutathione (GSH) and metals present in physiological systems will be discussed. This manuscript covers only dyes bearing small selenium- and tellurium-containing heterocycles.

A mild solvent-free protocol for the promotion of the Diels–Alder reactions of simple dienes and p -benzoquinones, catalyzed by a mixture of iron(III) chloride on Aerosil ® silica is reported.

We described herein a total synthesis of 1,4-dideoxy-1,4-imino-l-arabinitol [(2S,3S,4S)-2-(hydroxymethyl)pyrrolidine-3,4-diol, LAB-1], a polyhydroxylated pyrrolidine, which has been demonstrated to be a selective and potent α-glycosidase inhibitor. The main features of our approach are its shortness, efficiency, and simplicity. The total synthesis was accomplished in 6 steps with an overall yield of 12%, starting from a chiral optically active Morita–Baylis–Hillman (MBH) adduct prepared (without epimerization), from Garner’s aldehyde. As far as we know, this is the first report describing the total synthesis of this biologically active pyrrolidine by exploring the synthetic versatility of a MBH adduct.

Leishmania (Leishmania) infantum chagasi is one of the agents that cause visceral leishmaniasis. This disease occurs more frequently in third world countries, such as Brazil. The treatment is arduous, and is dependent on just a few drugs like the antimonial derivatives and amphotericin B. Moreover, these drugs are not only expensive, but they can also cause severe side effects and require long-term treatment. Therefore, it is very important to find new compounds that are effective against leishmaniasis. In the present work we evaluated a new group of synthetic amides against the promastigote and amastigote forms of L. infantum chagasi. The results showed that one of these amides in particular, presented very effective activity against the promastigotes and amastigotes of L. infantum chagasi at low concentrations and it also presented low toxicity for mammal cells, which makes this synthetic amide a promising drug for combating leishmaniasis.

A new fluorescent molecular probe (compound 7 ) assembled from the amide bond between the 1-pyrenecarboxylic acid ( 6 ) and 2-(butylselenyl)ethanamine ( 5 ) was designed, synthesized and its structure accurately characterized. The photophysical properties of 7 were evaluated among a wide range of metallic cations (Na + , K + , Ca 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Pb 2+ , Hg 2+ , Ag + , Al 3+ , Fe 3+ , Ga 3+ and Cr 3+ ) in water and in acetonitrile, which showed selective interaction with Hg 2+ . However, the sensing mechanism was found to be different in each solvent. Dynamic light scattering (DLS) studies revealed that compound 7 organizes itself as monodisperse aggregates in aqueous solution, nonetheless, as Hg 2+ was added to the aqueous solution, disruption of aggregates was observed, resulting in a coordination complex under strong CHEQ (Chelation-Enhanced Fluorescent Quenching). Conversely, in acetonitrile solution, 7 exhibited monomeric pyrene emissive pattern and, as the addition of Hg 2+ proceeded, a coordination compound of excimer-type fluorescence emission was observed. UV–vis absorption, steady state, and time-resolved emission spectroscopy were employed. The stoichiometry of the 7 -Hg 2+ complexes was found to be 1:1 for both aqueous ( log β = 6.19 ± 0.009) and acetonitrile (log β = 8.59 ± 0.04) solutions. The lowest value of a detectable amount of 0.15 μmol/L for Hg 2+ was achieved for fluorescence measurements in aqueous solution. The aqueous system was applied for the detection of Hg 2+ in real samples of spring water, where the added amounts of the analyte could be detected and quantified.

A range of hydroxypropargylpiperidones were efficiently obtained by a one-pot three-component coupling reaction of aldehydes, alkynols, and a primary amine equivalent (4-piperidone hydrochloride hydrate) in ethyl acetate using copper(I) chloride as a catalyst. The developed protocol proved to be equally efficient using a range of aliphatic aldehydes, including paraformaldehyde, and using protected and unprotected alkynols.

This paper describes a surface-enhanced Raman scattering (SERS) systematic investigation regarding the functionalization of gold (Au) and silver (Ag) nanoparticles with diphenyl dichalcogenides, i.e. diphenyl disulfide, diphenyl diselenide, and diphenyl ditelluride. Our results showed that, in all cases, functionalization took place with the cleavage of the chalcogen–chalcogen bond on the surface of the metal. According to our density functional theory calculations, the molecules assumed a tilted orientation with respect to the metal surface for both Au and Ag, in which the angle of the phenyl ring relative to the metallic surface decreased as the mass of the chalcogen atom increased. The detected differences in the ordinary Raman and SERS spectra were assigned to the distinct stretching frequencies of the carbon–chalcogen bond and its relative contribution to the ring vibrational modes. In addition, the SERS spectra showed that there was no significant interaction between the phenyl ring and the surface, in agreement with the tilted orientation observed from our density functional theory calculations. The results described herein indicate that diphenyl dichalcogenides can be successfully employed as starting materials for the functionalization of Au nanoparticles with organosulfur, organoselenium, and organotellurium compounds. On the other hand, diphenyl disulfide and diphenyl diselenide could be employed for the functionalization of Ag nanoparticles, while the partial oxidation of the organotellurium unit could be detected on the Ag surface. Copyright © 2011 John Wiley & Sons, Ltd.

The total synthesis of (−)-Blastmycinolactol, (+)-Blastmycinone, (−)-NFX-2, and (+)-Antimycinone was accomplished in few steps in high yields and ee, starting from enantiomerically enriched ( S )- Z -vinylic hydroxytellurides.

Enantiomerically pure (R)- and (S)-γ-hydroxy-organochalcogenides are prepared using poly-[R]-3-hydroxybutanoate (PHB) as the starting material.

Lithium and magnesium organotellurolates were reacted with lactones producing the corresponding tellurocarboxylic acids. Treatment of the reaction mixture with lithium aluminum hydride allowed the isolation of the corresponding hydroxytellurides in a one-pot operation.

A C–O-dianionic zincate was generated by a Te/Li exchange reaction of an alkyltelluride, followed by Li/Zn transmetallation and reaction with methyllithium. The reaction between the enantiomerically pure (99% ee) (R)-dianionic zincate and benzoyl chloride led to 3-hydroxy-1-phenyl pentanone with total retention of the carbon configuration (99% ee). Similar results were obtained using the corresponding Lipshutz cyanocuprates.