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Menthol is a monocyclic monoterpene with a distinct flavor that is frequently utilized in a variety of food and medicinal items. In this study, a sensitive method based on quartz crystal microbalance (QCM) with gold nanoparticles amplification was developed. A gold chip was initially modified with mono(6-mercapto-6-deoxy)-β-cyclodextrin (SH-β-CD) through Au-S affinity binding. When menthol is absent, the host–guest interaction brings ferrocene (Fc) labeled-ssDNA (Fc-ssDNA) to enter the SH-β-CD cavity. The hybridization between Au nanoparticles functionalized-ssDNA (AuNPs-ssDNA) and Fc-ssDNA produces a significant frequency shift. However, in the presence of menthol, the inclusion competition between Fc and menthol reduces AuNPs-ssDNA modification on the chip surface. In this case, the change of QCM frequency is greatly reduced by menthol. Thus, menthol determination is accomplished by measuring the change in QCM frequency with a linear range from 10−8 M to 10−2 M and a limit of detection of 7.81 nM, which is superior to previously reported results. The method has also been applied in real samples such as mint and essential oil with satisfactory results. [ABSTRACT FROM AUTHOR]

AbstractSmart wormlike micelles (WLMs) that respond to environmental stimuli and display tunable rheological properties have attracted considerable interest. However, the responsive surfactants in the smart WLMs are always commercially unavailable. Herein, we report the preparation of CO2/N2 and redox dual-stimuli responsive wormlike micelles (WLMs) using sodium ferrocenecarboxylic acid (FA), hexadecyl trimethyl ammonium bromide (CTAB), and N,N-dimethylhexadecylamine (CDA), which are all commercially available compounds. The ferrocene group in FA can be reversibly switched between its oxidized and reduced forms by redox reactions, which would alter the hydrophilic properties of FA. Consequently, by alternately adding H2O2 and NaBH4, WLMs can be reversibly destoryed and reformed because of the redox-responsiveness of FA. Moreover, WLMs can also be switched on and off by cyclically bubbling CO2 and N2, resulting from the reversible protonation of CDA. The multi-stimuli responsive WLMs (CTAB-FA-CDA) may have potential applications in oil recovery and fluid drag reducers. [ABSTRACT FROM AUTHOR]

We investigated how the post-synthesis treatment of tetradecylphosphonic acid-capped CdTe (TDPA-CdTe) QDs with CdCl2 and oleylamine (OAm) affected subsequent ligand-exchange reactions with ferrocenylhexanethiol (FcC6SH) and the dynamics and yield of photoinduced hole transfer from CdTe to adsorbed ferrocenylhexanethiolate (FcC6S-). CdCl2/OAm treatment promoted an 8-fold increase of the average number of adsorbed FcC6S- ligands ( N FcC 6 S − ) per CdTe QD; N FcC 6 S − increased with the concentration of FcC6SH and reached a maximum of 198 ± 5. Higher per-QD loadings of FcC6S- increased the overall ensemble rate constant of CdTe-to-FcC6S- hole transfer (kNht), which reached (3.0 ± 0.4) × 109 s−1, and the efficiency of hole transfer (ηht), which reached (98.2 ± 0.3)%. Values of kNht increased monotonically with N FcC 6 S − ; at relatively low loadings of FcC6S−, kNht varied linearly with N FcC 6 S − , indicating that hole-transfer pathways were additive. The intrinsic rate constant of hole transfer per adsorbed FcC6S− (kht), (2.75 ± 0.19) × 107 s−1, was 10-fold higher for CdCl2/OAm-treated CdTe QDs than for TDPA-CdTe QDs. Surface-anchoring thiolates did not trap photogenerated holes; instead, holes were transferred to the Fe(II) center of FcC6S−. Treatment of CdTe QDs with CdCl2 and OAm thus promoted ligand-exchange with FcC6S−, accelerated excited-state hole transfer, and afforded tunability of charge-transfer dynamics. [ABSTRACT FROM AUTHOR]

With the interest and knowing the importance of ferrocenyl conjugates, a direct amidation of ferrocenyl aldehyde has been developed under feasible conditions. Varieties of amines has been oxidatively coupled with ferrocene aldehyde in the presence of highly economical and robustly stable iron chalcogenide ironcarbonyl clusters [Fe3E2(CO)9, E= S, Se, and Te] and TBHP. The reaction worked in greener solvent water at a moderate temperature of 70 °C and the ferrocenyl‐amides in just 30 minutes. All the varieties of amines were found to be well tolerated for the present method, and due to the high medicinal importance of ferrocenyl‐amides, sole focus of this report was concentrates on the synthesis of various new ferrocenyl‐amides in good to excellent amounts. [ABSTRACT FROM AUTHOR]

2,8-Dithia-5-aza-2,6-pyridinophane (L1) has been used as a receptor unit in the construction of the conjugated redox chemosensor 5-ferrocenylmethyl-2,8-dithia-5-aza-2,6-pyridinophane (L3). In order to further explore the coordination chemistry of L1, and comparatively, that of its structural analogue 2,11-dithia-5,8-diaza-2,6-pyridinophane (L2), featuring two secondary nitrogen atoms in the macrocyclic unit, the crystal structures of the new synthesised complexes [Pb(L1)(ClO4)2]·½CH3CN, [Cu(L2)](ClO4)2·CH3CN and [Cd(L2)(NO3)]NO3 were determined by X-ray diffraction analysis. The electrochemical response of L3 towards the metal ions Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+ was investigated by cyclic voltammetry (CV) in CH2Cl2/CH3CN 0.25:1 (v/v) mixture. Upon addition to L3 of increasing amounts of the aforementioned metal cations, the wave corresponding to the Fc+/Fc redox couple of the un-complexed L3 was gradually replaced by a new reversible wave at more positive potentials and corresponding to the Fc+/Fc redox couple of the complexed ligand. The maximum anodic shift of the ferrocene oxidation wave is observed in the presence of Pb2+ (230 mV), to which corresponds a reaction coupling efficiency (RCE) value as large as 7.9 × 103. The response selectivity of L3 is discussed in reference to the optical selectivity observed for conjugated chemosensors featuring L1 as receptor unit and different fluorogenic fragments as signalling units. [ABSTRACT FROM AUTHOR]

In this paper, the clean high yielding, synthesis, and structure of the tetraphosphine ligand, 1,1′,2,2′-tetrakis-(di-isopropyl-phosphino)ferrocene, (tdipf), is described. In addition, improved synthesis methods for 1,1′,2,2′-tetrakis(diphenylphosphino)ferrocene, (tppf), and 2,2′-bis-(diphenylphosphino)-1,1′-dibromoferrocene are also reported, and the synthetic method is generalised to include the synthesis of 3,3′-bis-(diphenylphosphino)-1,1′,2,2′-tetrabromoferrocene. The related ligands 2,2′-bis-(iso-propylphosphino)-1,1′-bis-diphenylphosphinoferrocene (diprdppf) and 2,2′-bis-(di-isopropylphosphino)-dibromoferrocene have also been prepared and characterised. The crystal structure of the square planar bimetallic nickel (II) dichloride of tdipf is also described, together with a brief NMR study investigating the synthesis of this and related metal complexes. The crystal structures of the palladium and platinum dichloride complexes of 2,2′-bis-(di-isopropylphosphino)-1,1′-dibromoferrocene, bpdbf, are also discussed in the context of comparison with previously known crystal structures in the same general family. A general discussion on the synthetic methodology is given, along with indications for future research that other researchers might explore. [ABSTRACT FROM AUTHOR]

Ferrocene (Fc) has long been celebrated for its remarkable redox properties and structural versatility, making it a cornerstone of electrochemical sensor development. While extensive research has focused on cation detection using Fc-based systems, the equally critical recognition of neutral and anionic molecules remains underexplored despite their significance in biological, environmental, and industrial contexts. This review addresses this gap by exploring the latest advancements in Fc-based electrochemical sensors designed to overcome the unique challenges posed by these species—including diverse geometries, high hydration enthalpies, and the absence of formal charge. Molecular architectures such as amide-functionalised receptors, urea derivatives, Lewis acid-containing receptors, triazolium, and carboxylic acid-containing systems are examined, highlighting how these sensors achieve high selectivity and sensitivity. Furthermore, the influence of solvent environments on sensor performance is discussed, providing a critical analysis of how different receptor functionalities and solvents affect sensor behaviour. Emphasising the advantages of redox-based detection, this review aims to inspire further innovation in developing Fc-based technologies for detecting neutral and anionic species. [ABSTRACT FROM AUTHOR]

Background/Objectives: New drugs are required for the treatment of liver cancers and protozoal parasite infections. Analogs of the known anticancer active and antileishmanial 2′,4′,6′-trimethoxychalcone SU086 were prepared and investigated. Methods: The chalcones were prepared according to the Claisen–Schmidt condensation protocol and analyzed. They were tested for activity against two liver cancer cell lines (HepG2 and HuH-7) and protozoal parasites (Toxoplasma gondii and Leishmania major). Unspecific toxicity and expression of Hsp90 and Hsp70 upon treatment were analyzed in liver cancer cells. Results: A new chalcone, 2′,4′,6′-trimethoxy-3-pentafluorosulfanylchalcone (246TMP-3SF5), with a pentafluorosulfanyl (SF5) substituent showed pronounced activities against liver cancer cells and T. gondii parasites which were superior to the activities of the parent chalcone SU086 in these models. In contrast, SU086 and its anthracene analog 2′,4′,6′-trimethoxy-9-anthracenylchalcone (246TMP-Anth) were most active against L. major promastigotes. The new SF5-substituted chalcone behaved like the known Hsp90 inhibitor 17-AAG and upregulated Hsp70 expression in liver cancer cells. Conclusions: The SF5-substituted SU086 analog has potential to become a new drug for the therapy of hepatoma and toxoplasmosis. [ABSTRACT FROM AUTHOR]

Trypanosomatids are the etiologic agents of numerous parasitic diseases that cause significant morbidity and mortality in millions of people and animals around the world. Approved antitrypanosomatid agents are limited by several drawbacks, such as severe toxicity, lengthy treatment, need for hospitalization, and susceptibility to drug resistance. Consequently, parasitic diseases remain a substantial public health problem, and new drugs are required, especially drugs suitable for rural health systems that have limited resources. In an attempt to find antitrypanosomatid agents to address this problem, we report here on the synthesis and biological efficacy of ferrocene derivatives of nifuroxazide and nitrofurazone, which were designed by replacing the nitrofuran scaffold within their structures with the ferrocene moiety. The 1,2‐disubstituted ferrocene intermediates 8 and 9, featuring amine and carboxaldehyde groups, exhibited the best in vitro antiamastigote activity against Leishmania major strain NIH S and Leishmania donovani strain 9515, respectively. Ferroxazide derivative 15 was revealed as a mammalian cell nontoxic hit compound against Trypanosoma congolense strain IL3000 trypomastigotes; however, no in vivo treatment efficacy was observed against T. congolense strain IL3000‐infected BALB/c mice during a preliminary animal study. The synthesized ferrocene derivatives were poorly soluble in the in vitro and in vivo testing media, hindering uniform sampling and dosing. This study's outcome indicates that replacing the 5‐nitrofuran moiety with ferrocene did not increase antitrypanosomatid activity compared to the nitrofuran parent drugs nifuroxazide and nitrofurazone. [ABSTRACT FROM AUTHOR]

The effect of calcination temperature in air of finely dispersed boehmite powders with ferrocene adsorbed at room temperature from n-hexane solution on X-ray diffraction patterns and EPR spectra of calcined samples was studied. It has been shown that calcination in air of boehmite samples with adsorbed ferrocene leads to the decomposition of ferrocene molecules, stabilization of two types of magnetic centers in the structure of boehmite (at 200 and 400°C) and aluminum oxide (at 600°C) caused by two types of magnetic centers -Fe3+ ions with g-factor values, equal to 4.3 and 2.0. The signal at g = 4.3 is attributed to isolated Fe3+ ions in the structure of boehmite and aluminum oxide in a local field of oxygen anions with a rhombic environment. The signal at g = 2.0 is most likely due to Fe3+ ions bound by dipole interaction for samples with a low concentration of supported ferrocene (<0.1 wt.%) and superpara/ferromagnetic FeOx particles for samples of the calcination product of boehmite with a high content (>0.1 wt.%) of ferrocene. With increasing content of adsorbeded ferrocene, concentrations of Fe3+ ions with g-factor values equal to 4.3 and 2.0 grow disproportionately, and mainly the growth of the concentration of superpara/ferromagnetic FeOx particles on the oxide surface is observed. [ABSTRACT FROM AUTHOR]

By highly efficient ligand‐exchange strategy, atomically precise Au8Pd1(PPh3)82+ (PPh3=triphenylphosphine) cluster can be transformed into a Au8Pd1(DPPF)42+ (DPPF=1,1′‐bis(diphenylphosphino)ferrocene) cluster that can maintain the atomic‐packing structure but overcome the lability of Au8Pd1(PPh3)82+. Catalytic evaluation for the CO2 hydrogenation coupled with o‐phenylenediamine demonstrates that the Au8Pd1(DPPF)42+ catalyst can remarkably enhance both activity and stability compared to the Au8Pd1(PPh3)82+ catalyst. More notably, the direct construction of a two‐dimensional metal–organic framework (2D MOF) can be elaborately accomplished in the formylation process of o‐phenylenediamine, CO2 and H2 with zinc nitrate enabled by the Au8Pd1(DPPF)42+ catalyst. The 2D MOF further enables the capture and transformation of CO2 to combine in the organic synthesis with epoxides under mild conditions. This work provides opportunities for creating highly active cluster sites for the chemical recycling of CO2. [ABSTRACT FROM AUTHOR]

The reversible modulation of chirality has gained significant attention not only for fundamental stereochemical studies but also for numerous applications ranging from liquid crystals (LCs) to molecular motors and machines. This requires the construction of switchable molecules with (multiple) chiral elements in a highly enantioselective manner, which is often a significant synthetic challenge. Here, we show that the dimerization of an easily accessible enantiopure planar chiral ferrocene‐indanone building block affords a multi‐stimuli‐responsive dimer (FcD) with pre‐determined double bond geometry, helical chirality, and relative orientation of the two ferrocene motifs in high yield. This intrinsically planar chiral switch can not only undergo thermal or photochemical E/Z isomerization but can also be reversibly and quantitatively oxidized to both a monocationic and a dicationic state which is associated with significant changes in its (chir)optical properties. Specifically, FcD acts as a chiral dopant for cholesteric LCs with a helical twisting power (HTP) of 13 μm−1 which, upon oxidation, drops to near zero, resulting in an unprecedently large redox‐tuning of the LC reflection color by up to 84 nm. Due to the straightforward stereoselective synthesis, FcD, and related chiral switches, are envisioned to be powerful building blocks for multi‐stimuli‐responsive molecular machines and in LC‐based materials. [ABSTRACT FROM AUTHOR]

A biosensor for the determination of the phenol index in water bodies has been developed using enzymes immobilized on the redox-active polymer surface of a graphite paste electrode. Tyrosinase, laccase, and bacterial cell membrane fractions were used as biological materials. Redox polymers based on bovine serum albumin (BSA) and various electron transport mediators were synthesized for immobilization. It has been shown that a redox polymer based on ferrocene (FC) combined with single-walled carbon nanotubes (SWCNTs) is more promising for use in biosensors than a polymer based on safranin (SAF) based on electrochemical and analytical parameters. The best results were obtained with the "BSA-FC-SWCNT-tyrosinase" bioanalytical system, which has a lower limit of detectable concentrations of 1 × 10⁻³ mg/L, indicating the possibility of monitoring water environments with a phenol concentration corresponding to the maximum permissible concentration (MPC). The maximum analytical signal was generated at a temperature of 30 °С and a pH of 6.8. The biosensor was stable at concentrations of heavy metal ions up to 100 times the MPC, as well as at NaCl concentrations up to 5%. The system was tested on river water samples containing phenol. A statistical analysis of the results showed no significant difference between the biosensor results and those of standard analytical methods. The proposed approach will significantly reduce the analysis time, its labor intensity and cost. [ABSTRACT FROM AUTHOR]

The poor prognosis of glioblastoma multiforme, inadequate treatment options, and growing drug resistance urge the need to find new effective agents. Due to the significant anti-cancer potential of harmicens, hybrid compounds which comprise harmine/β-carboline and ferrocene moiety, we investigated their antiglioblastoma potential in vitro and mechanism of action (inhibition of DYRK1A, Hsp90, anti-oxidative activity). The results have shown that triazole-type harmicens, namely ., with a ferrocene moiety in C-3 position of the β-carboline ring (IC50 = 3.7 ± 0.1 µmol L–1, SI = 12.6) and ., the C-6 substituted harmicene (IC50 = 7.4 ± 0.5 µmol L–1, SI = 5.8) exert remarkable activity and selectivity against human malignant glioblastoma cell line (U251) in vitro. On the other hand, amide-type harmicens 10, 12, and 14 exhibited strong, but non-selective activity, in the low micro-molar range. Mechanistic studies revealed that among active compounds, amide-type harmicens 12 and 14 inhibit DYRK1A and Hsp90 CTD, whereas compound 14 showed pronounced antioxidative activity. Therefore, the antiproliferative activity of harmicens might be a combination of complex molecular interactions.

Chemical modification of carbonaceous materials is a convenient and reliable approach for the permanent fabrication of functional moieties. Among different linkers, diazirines offer a photogenerated reactive carbene that can insert into X–H (X; O, N) and add to π bonds to tether a variety of moieties on the surface of carbonaceous materials. Explicitly, 3‐phenyl‐3‐(trifluoromethyl)‐3H‐diazirine is more thermally and chemically stable within the diazirine family. Here, we synthesized 3‐(ferrocenylalkyloxy)‐3‐(trifluoromethyl)‐diazirine derivatives and utilized them to covalently modify the surface of glassy carbon (GC). The photogenerated carbene enabled the tethering of the ferrocene (Fc) to the surface of a GC electrode (GCE). The modified surface properties were investigated using different electrochemical techniques, ellipsometry spectroscopy, and scanning electron microscopy. Electrochemical surface responses in KCl and Ru(NH3)63+ solutions clearly exhibited ferrocene redox behavior and surface blocking during modification, respectively. Surface analysis results revealed a clear correlation between the thickness and capacitance current of the modified surface. More importantly, the obtained electrochemistry data show substantial chemical stability of the covalently tethered Fc on the GCE surface in both aqueous and nonaqueous media. The presented work offers an approach for the on‐demand photochemical formation of carbene from diazirines to add functionality for applications of modified electrodes in electrocatalysis and sensing. [ABSTRACT FROM AUTHOR]

This study presents the development of a novel planar chiral ferrocene‐based NHC ligand and its corresponding metal complexes. The key unit of the imidazolium backbone, planar chiral ortho‐isopropyl ferrocenyl amine, was synthesized starting from (S)‐Ugi's amine. Imidazolium was obtained through the sequential condensation of glyoxal with ferrocenyl amine, followed by the ring‐closure of 1,3‐diferrocenyldiimine with chloromethylethyl ether. Chiral imidazolylidene NHC (IFcPr) metal complexes were prepared by treating imidazolium with silver oxide or base followed by transmetalation with appropriate metal salts. The steric and electronic properties of the IFcPr ligand were assessed using %Vbur and TEP, respectively. These assessments indicated that the ligand was as bulky as the adamantyl NHC ligand and exhibited strong donor ability similar to that of a triazolylidene NHC ligand. The catalytic performance of the copper and palladium complexes was evaluated in the asymmetric borylation of ethyl cinnamate and Suzuki–Miyaura coupling reactions, respectively. The IFcPr−Cu complex catalyzed the borylation of ethyl cinnamate with bis(pinacolato) diboron, followed by oxidation to yield the hydroxy ester with 58 % yield and 30 % ee. In contrast, the IFcPr−Pd‐PEPPSI complex provided the axial chiral binaphthyl compound with 59 % yield and 51 % ee at a low catalyst loading (0.1 mol %, TON=590). [ABSTRACT FROM AUTHOR]

A multi‐gram scale synthesis of ferrocenetriflone was optimised from ferrocenesulfonyl fluoride and Me3SiCF3 (Ruppert reagent). Enantioselective deprotolithiations were then optimised using alkyllithiums in the presence of catalytic (+)‐sparteine to afford 2‐substituted ferrocene triflones in 79–84% ee. The use of chiral lithium amides in the presence of in situ traps was also optimised and was found to outperform alkyllithium⋅chiral diamine chelates for the first time in the ferrocene series, with 89–93% ee. Crystallisation of derivatives afforded enantiopure compounds that were engaged in deprotolithiation‐electrophilic trapping sequences, a halogen 'dance' reaction and transition metal‐promoted coupling to afford a wide range of variously polysubstituted ferrocene triflones. [ABSTRACT FROM AUTHOR]

Lead halide perovskite nanocrystals (NCs) rapidly emerge as promising materials for photovoltaics. However, to fully harness their potential, efficient charge extraction is crucial. Despite rapid advancements, the specific active sites where acceptor molecules interact remain inadequately understood. Surface chemistry and interfacial properties are pivotal, as they directly impact charge transfer efficiency and overall device performance. This study identifies and maps binding sites for hole transporters, examining their influence on charge transfer dynamics through ligand engineering with 2,3‐dimercaptopropanol (DMP), a compound with a strong affinity for lead (Pb). DMP effectively passivates Pb sites in CsPbBr3 (CPB) NCs, enhancing photoluminescence (PL) by forming stable chelating bonds. DMP‐modified CPB nearly completely suppresses hole transfer to ─COOH‐functionalized ferrocene (FcA) and partially suppresses transfer to ─NMe2‐functionalized ferrocene (FcAm), suggesting an alternative hole extraction pathway for FcAm. This is further supported by enhanced hole transfer in bromine‐excess CPB (CPB‐Br(XS)) synthesized via SOBr2 treatment. The distinct binding interactions and charge transfer dynamics are validated through steady‐state and time‐resolved PL, along with transient absorption spectroscopy. These findings underscore the role of strategic ligand engineering in enhancing perovskite NC‐charge acceptor interactions, enabling better charge extraction, higher solar cell efficiency, and reduced lead toxicity through strong Pb binding. [ABSTRACT FROM AUTHOR]

An efficient method has been developed for the synthesis of siloxane aerogels with a hybrid structure built into the polymer structure. At the initial stage, a gel was obtained by polycondensation of tetraethoxysilane and ferrocene-containing alkoxysilanes, catalyzed by BF3 ⋅ Et2O in acetone. The transformation of gels into aerogels was performed using supercritical carbon dioxide (SC-CO2). The aerogel samples were characterized in detail by Mössbauer spectroscopy and nitrogen adsorption methods, and the density of the materials was determined. The iron content in the resulting aerogels varied from 3.6 to 8.7 wt % (or 11.9–28.7 wt % ferrocene units). [ABSTRACT FROM AUTHOR]

The integration of organometallic compounds with metal nanoparticles can, in principle, generate hybrid nanocatalysts endowed with augmented functionality, presenting substantial promise for catalytic applications. Herein, we synthesize an atomically precise metal cluster (Ag9Cu6) catalyst integrated with alkynylferrocene molecules (Ag9Cu6‐Fc). This hybrid catalyst design facilitates a continuous electron transfer channel via an ethynyl bridge and establishes a distinctive local chemical environment, resulting in remarkably enhanced catalytic activity in CO2 electroreduction. The Ag9Cu6‐Fc catalyst achieves a record‐high product selectivity of CO Faradaic efficiency of 100 % and an industrial‐level CO partial current density of −680 mA/cm2, surpassing the performance of the Ag9Cu6 cluster (62 % and −230 mA/cm2, respectively) without ferrocene functionalization in a membrane electrode assembly cell. Operando experimental and computational findings offer valuable insights into the role of ferrocene functionalization in synergistically improving the catalytic performance of metal clusters, propelling the advancement of metallic‐organometallic hybrid nanoparticles for energy conversion technologies. [ABSTRACT FROM AUTHOR]

Developing new methods to control the size and shape of the helical structures adopted by foldamers is highly important as the secondary structure displayed by these supramolecular scaffolds often dictates their activity and function. Herein, we report on a systematic study demonstrating that the helical pitch of ortho‐azobenzene/2,6‐pyridyldicarboxamide foldamers can be readily controlled through the nature of the terminal functionality. Remarkably, simply through varying the end group of the foldamer, and without modifying any other structural features of the scaffold, the helical pitch can be over doubled in magnitude (from 3.4 Å–7.3 Å). Additionally, crystallographic analysis of a library ten foldamers has identified general trends in the influence of a range of terminal functionalities, including carboxylbenzyl (Cbz), diphenylcarbamyl (N(Ph)2), ferrocene (Fc) and tert‐butyloxycarbonyl (Boc), in controlling the folding behaviour of these supramolecular scaffolds. These studies could prove useful in the future development of functional foldamers which adopt specific sizes and shapes. [ABSTRACT FROM AUTHOR]

Two chiral ferrocenylamine alcohols of (R)-[Fe(η5-C5H5){η5-C5H4CH2NHCH(iPr)(CH2OH)}] (1) and (R)-[Fe(η5-C5H5){η5-C5H4CH2NHCH(C6H5)(CH2OH)}] (2) were synthesized by condensation reaction of ferrocenylformaldehyde and chiral aminoalcohols followed by the reduction with sodium borohydride. The crystal structures of the two compounds were determined by single crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group P21212 with a = 16.600(8) Å, b = 28.990(14) Å, c = 6.531(3) Å, and Z = 8. Compound 21.13H2O crystallizes in the monoclinic space group I2 with a = 22.671(4) Å, b = 6.2481(10) Å, c = 22.112(4) Å, β = 96.763(12)°, and Z = 8. [ABSTRACT FROM AUTHOR]

Surfactants are very important compounds that are ubiquitous in biological systems and detergents. Among them, ferrocene surfactants are a very valuable class of stimuli-responsive materials since the presence of ferrocene moiety discloses the chance to control and even modify their amphiphilic properties via a redox-induced change in the surfactant charge. In this paper, we report a new ferrocene-based surfactant: a ferrocene C-3 derivative of cholic acid, a non-classical surfactant. The title compound of this work was meant to show the significant self-assembly behaviour typical of bile salts, improved by the presence of the aromatic ferrocene subunit. We intended to demonstrate that the presence of the redox mediator should provide the derivative with sensitivity to an oxidative stimulus and control over the aggregation properties. The title compound was prepared in two steps from easily accessible precursors, and its optical properties were investigated through UV-Vis absorption spectroscopy. The determination of its critical micellar concentration and redox potential confirmed this derivative's amphiphilic nature and its tendency to be reversibly oxidized. [ABSTRACT FROM AUTHOR]

Ferrociphenols are anticancer organometallic molecules bearing a ferrocene group linked, at least, to one para-phenol moiety via a double bond. Up to the present, their biological activity has been thought to be linked to their oxidation within cells to form a reactive quinone-methide metabolite with the participation of this central double bond. To prove this assertion, the alkenyl entity of ferrociphenol 1a (1,1-bis-(4-hydroxyphenyl)-2-ferrocenylbut-1-ene) was reduced by triethylsilane in an acidic medium to obtain the alkyl counterpart 1,1-bis(4-hydrophenyl)-2-ferrocenylbutane. 1,1-bis(4-hydrophenyl)-2-ferrocenylbutane was fully characterized by 1H NMR (including COSY), 13C NMR, HRMS, IR, elemental analysis and X-ray diffraction (XRD). Although missing the central double bond, this compound remains biologically active, opening the way to a new family of anticancer ferrocene-containing molecules. [ABSTRACT FROM AUTHOR]

The synthesis and characterisation (UV-Vis, IR, HRESI-MS, 1H and 13C NMR spectroscopies, electrochemistry) is reported of the novel title material (1: alternatively named rac-1-(2′-benzothiazolyl)-2-ferrocenyl-2-propanol): a rare example of a ferrocenyl-benzothiazole hybrid species. Compound 1 is produced by the low temperature reaction of acetylferrocene (3) with a solution of the methyl anion derived via the deprotonation of 2-methyl-1,3-benzothiazole. The yield of 1 is moderate (34%) after purification and is an air and thermally stable solid under ambient conditions. Attempts to sublime 1, however, result in decomposition with one of the products being identified (NMR) as 3. The spectroscopic features of 1 are presented. Attempts to obtain suitable crystalline material of 1 for a single crystal X-ray diffraction study were unfortunately unsuccessful. Compound 1 also does not form stable coordination complexes with various metal salts (e.g., Ni[2+], Co[2+], etc.) under the conditions tested. [ABSTRACT FROM AUTHOR]

The metallocenyl-containing β-diketonato rhodium(I) dicarbonyl complexes of [Rh(FcCOCHCOR)(CO)2] where R = CF3, 10; Fc = ferrocenyl = FeII(C5H5)(C5H4), 11; Rc = ruthenocenyl = RuII(C5H5)(C5H4), 12; and Oc = osmocenyl = OsII(C5H5)(C5H4), 13 were synthesized. Complexes 10–13 were then subjected to an electrochemical study utilizing cyclic voltammetry (CV), square wave voltammetry (SWV), and linear sweep voltammetry (LSV) in the non-coordinating solvent/supporting electrolyte medium CH2Cl2/0.1 mol dm−3 [N(nBu)4][B(C6F5)4]. The formal reduction potential for the electrochemical reversible Fc0/+ couples in 10–13 was identified in the range 0.156 ≤ Eo′ ≤ 0.328 V while the electrochemically irreversible osmocenyl and ruthenocenyl oxidations were observed at peak anodic potentials of Epa = 0.640 V and Epa = 0.751 V, respectively. Resolution between the closely overlapping CV-determined Fc0/+ and RhI/II couples was too poor for unambiguous measurement of the RhI/II redox potential, but square wave voltammetry allowed estimates of Eo′ (RhI/II) in the range 0.156 ≤ Eo′ ≤ 0.398 V. FT-IR spectroelectrochemistry confirmed the one-electron oxidation of RhI by the appearance of CO vibrational bands at stretching frequencies, which are associated with rhodium(II) and not rhodium(III). Cytotoxicity tests on 10 (IC50 = 19.2 µM) showed it to be substantially less cytotoxic than the free β-diketone, FcCOCH2COCF3, and [Rh(FcCOCHCOCF3)(cod)]. [ABSTRACT FROM AUTHOR]