Ferrocene-containing dendrimers are dendrimers that contain ferrocene substituents. Some ferrocene-containing dendrimers feature ferrocene cores and others do not. All feature with peripheral ferrocene groups. [1] [2]
Ferrocene-containing dendrimers are dendrimers that contain ferrocene substituents. Some ferrocene-containing dendrimers feature ferrocene cores and others do not. All feature with peripheral ferrocene groups. [1] [2]
Ferrocene-containing dendrimers can be synthesized by both convergent and divergent methods. Some of the first dendrimers of this type, were made by attaching ferrocene units to small silicon containing dendrimers. [3]
Dendrimers with peripheral ferrocene groups are usually synthesized by attaching ferrocene to the core by either olefin metathesis or by hydrosilylation. [1] As an example, tetraallylsilane undergoes Pt-catalyzed hydrosilylation to form the core. This core was then reacted with ferrocenyllithium to form 1. [4] Convergent approaches can also be used to make dendrimers with peripheral ferrocene. As an example, figure 1 shows a 54-ferrocene dendrimer which was synthesized by a fast convergent approach. [5]
Dendrimers with ferrocene cores have been synthesized by decorating suitably functionalized ferrocenes, e.g., decaallylferrocene. [1]
synthesis Ferrocene-containing dendrimers can be synthesized by convergence and diffusion methods. By linking ferrocene units to small silicon-containing dendrimers, some of these first-type dendrimers can be made. [3]
Dendritic macromolecules with peripheral ferrocene groups are usually synthesized by linking ferrocene to the core through olefin metathesis or hydrosilylation [1]. For example, tetraallyl silane undergoes Pt-catalyzed hydrosilylation to form a core. The core is then reacted with ferrocenyl lithium to form 1. [4]. The convergence method can also be used to make dendrimers with peripheral ferrocene. en.china.cn is a good place to supply polymer resin
No applications have been identified for ferrocene-containing dendrimers. They exhibit multielectron redox indicating that the ferrocenyl moieties are essentially noninteracting redox centers. [4] [5]
Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkaline, alkaline earth, and transition metals, and sometimes broadened to include metalloids like boron, silicon, and tin, as well. Aside from bonds to organyl fragments or molecules, bonds to 'inorganic' carbon, like carbon monoxide, cyanide, or carbide, are generally considered to be organometallic as well. Some related compounds such as transition metal hydrides and metal phosphine complexes are often included in discussions of organometallic compounds, though strictly speaking, they are not necessarily organometallic. The related but distinct term "metalorganic compound" refers to metal-containing compounds lacking direct metal-carbon bonds but which contain organic ligands. Metal β-diketonates, alkoxides, dialkylamides, and metal phosphine complexes are representative members of this class. The field of organometallic chemistry combines aspects of traditional inorganic and organic chemistry.
Ferrocene is an organometallic compound with the formula Fe(C
5H
5)
2. The molecule consists of two cyclopentadienyl rings bound on opposite sides of a central iron atom. It is an orange solid with a camphor-like odor, that sublimes above room temperature, and is soluble in most organic solvents. It is remarkable for its stability: it is unaffected by air, water, strong bases, and can be heated to 400 °C without decomposition. In oxidizing conditions it can reversibly react with strong acids to form the ferrocenium cation Fe(C
5H
5)+
2.
Dendrimers are repetitively branched molecules. The name comes from the Greek word δένδρον (dendron) which translates to "tree". Synonymous terms for dendrimer include arborols and cascade molecules. However, dendrimer is currently the internationally accepted term. A dendrimer is typically symmetric around the core, and often adopts a spherical three-dimensional morphology. The word dendron is also encountered frequently. A dendron usually contains a single chemically addressable group called the focal point or core. The difference between dendrons and dendrimers is illustrated in the top figure, but the terms are typically encountered interchangeably.
The Bamford–Stevens reaction is a chemical reaction whereby treatment of tosylhydrazones with strong base gives alkenes. It is named for the British chemist William Randall Bamford and the Scottish chemist Thomas Stevens Stevens (1900–2000). The usage of aprotic solvents gives predominantly Z-alkenes, while protic solvent gives a mixture of E- and Z-alkenes. As an alkene-generating transformation, the Bamford–Stevens reaction has broad utility in synthetic methodology and complex molecule synthesis.
Alkane metathesis is a class of chemical reaction in which an alkane is rearranged to give a longer or shorter alkane product. It is similar to olefin metathesis, except that olefin metathesis cleaves and recreates a carbon-carbon double bond, but alkane metathesis operates on a carbon-carbon single bond.
Dihydroxylation is the process by which an alkene is converted into a vicinal diol. Although there are many routes to accomplish this oxidation, the most common and direct processes use a high-oxidation-state transition metal. The metal is often used as a catalyst, with some other stoichiometric oxidant present. In addition, other transition metals and non-transition metal methods have been developed and used to catalyze the reaction.
Ring-closing metathesis (RCM) is a widely used variation of olefin metathesis in organic chemistry for the synthesis of various unsaturated rings via the intramolecular metathesis of two terminal alkenes, which forms the cycloalkene as the E- or Z- isomers and volatile ethylene.
Chloroplatinic acid (also known as hexachloroplatinic acid) is an inorganic compound with the formula [H3O]2[PtCl6](H2O)x (0 ≤ x ≤ 6). A red solid, it is an important commercial source of platinum, usually as an aqueous solution. Although often written in shorthand as H2PtCl6, it is the hydronium (H3O+) salt of the hexachloroplatinate anion (PtCl2−
6). Hexachloroplatinic acid is highly hygroscopic.
The Shell higher olefin process is a chemical process for the production of linear alpha olefins via ethylene oligomerization and olefin metathesis invented and exploited by Royal Dutch Shell. The olefin products are converted to fatty aldehydes and then to fatty alcohols, which are precursors plasticizers and detergents. The annual global production of olefines through this method is over one million tonnes.
Transmetalation (alt. spelling: transmetallation) is a type of organometallic reaction that involves the transfer of ligands from one metal to another. It has the general form:
Hydrosilylation, also called catalytic hydrosilation, describes the addition of Si-H bonds across unsaturated bonds. Ordinarily the reaction is conducted catalytically and usually the substrates are unsaturated organic compounds. Alkenes and alkynes give alkyl and vinyl silanes; aldehydes and ketones give silyl ethers. Hydrosilylation has been called the "most important application of platinum in homogeneous catalysis."
Organoaluminium chemistry is the study of compounds containing bonds between carbon and aluminium bond. It is one of the major themes within organometallic chemistry. Illustrative organoaluminium compounds are the dimer trimethylaluminium, the monomer triisobutylaluminium, and the titanium-aluminium compound called Tebbe's reagent. The behavior of organoaluminium compounds can be understood in terms of the polarity of the C−Al bond and the high Lewis acidity of the three-coordinated species. Industrially, these compounds are mainly used for the production of polyolefins.
Silicon hydrides are organosilicon compounds that contain a silicon–hydrogen bond. Examples include phenylsilane (PhSiH3) and triethoxysilane ((EtO)3SiH).
A silsesquioxane is an organosilicon compound with the chemical formula [RSiO3/2]n. Silsesquioxanes are colorless solids that adopt cage-like or polymeric structures with Si-O-Si linkages and tetrahedral Si vertices. Silsesquioxanes are members of polyoctahedral silsesquioxanes ("POSS"), which have attracted attention as preceramic polymer precursors to ceramic materials and nanocomposites. Diverse substituents (R) can be attached to the Si centers. The molecules are unusual because they feature an inorganic silicate core and an organic exterior. The silica core confers rigidity and thermal stability.
Dehalogenation is a chemical reaction that involves the cleavage of C-halogen bond to form product. Dehalogenation can be divided into two subclasses: reductive dehalogenation and hydro dehalogenation.
Reductions with hydrosilanes are chemical reactions that involve the combination of an hydrosilane (R3SiH) with an organic substrate containing unsaturated or electron-withdrawing functionality. Products in which the electron-withdrawing group has been replaced by hydrogen or the unsaturated group has been hydrogenated result. Reductions with hydrosilanes has only specialized applications. In contrast, the related hydrosilation of alkenes is the basis of major technologies.
Decamethylferrocene or bis(pentamethylcyclopentadienyl)iron(II) is a chemical compound with formula Fe(C
5(CH
3)
5)
2 or C
20H
30Fe. It is a sandwich compound, whose molecule has an iron(II) cation Fe2+ attached by coordination bonds between two pentamethylcyclopentadienyl anions (Cp*−, (CH
3)
5C−
5). It can also be viewed as a derivative of ferrocene, with a methyl group replacing each hydrogen atom of its cyclopentadienyl rings. The name and formula are often abbreviated to DmFc, Me
10Fc or FeCp*
2.
Mesoionic carbenes (MICs) are a type of reactive intermediate that are related to N-heterocyclic carbenes (NHCs) and are used in scientific research in chemistry. Unlike simple NHCs, the canonical resonance structures of these carbenes are mesoionic: an MIC cannot be drawn without adding additional charges to some of the atoms. MICs re also called abnormal N-heterocyclic carbenes (aNHC) or remote N-heterocyclic carbenes (rNHC). A variety of free carbenes can be isolated and are stable at room temperature. Other free carbenes are not stable and are susceptible to intermolecular decomposition pathways. MICs do not dimerize according to Wanzlick equilibrium as do normal NHCs. This results in relaxed steric requirements for mesoionic carbenes as compared to NHCs. There are several mesoionic carbenes that cannot be generated as free compounds, but can be synthesized as a ligand in a transition metal complex. Most MIC transition metal complexes are less sensitive to air and moisture than phosphine or normal NHC complexes. They are also resistant to oxidation. The robust nature of MIC complexes is due to the ligand’s strong σ-donating ability. They are stronger σ-donors than phosphines, as well as normal N-heterocyclic carbenes due to decreased heteroatom stabilization. The strength of carbene ligands is attributed to the electropositive carbon center that forms strong bonds of a covalent nature with the metal. They have been shown to lower the frequency of CO stretching vibrations in metal complexes and exhibit large trans effects.
The Danheiser benzannulation is a chemical reaction used in organic chemistry to generate highly substituted phenols in a single step. It is named after Rick Danheiser who developed the reaction.
A lanthanocene is a type of metallocene compound that contains an element from the lanthanide series. The most common lanthanocene complexes contain two cyclopentadienyl anions and an X type ligand, usually hydride or alkyl ligand.