Niobium pentachloride or Niobium(V) chloride is the chloride of niobium and yellow fine crystalline powder. This inorganic compound is used in organic chemistry as a Lewis acid in activating alkenes for the carbonyl-ene reaction and the Diels-Alder reaction. Niobium chloride can also generate N-acyliminium compounds from certain pyrrolidines which are substrates for nucleophiles such as allyltrimethylsilane, the silyl enol ether of benzophenone and indole ^[1]. IUPAC nomenclature is a systematic way of naming organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC). ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... The molecular mass of a substance (less accurately called molecular weight and abbreviated as MW) is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The boiling point of a substance is the temperature at which it can change state from a liquid to a gas throughout the bulk of the liquid. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII alpha-numeric strings. ... General Name, Symbol, Number Niobium, Nb, 41 Chemical series Transition metals Group, Period, Block 5, 5, d Density, Hardness 8570 kg/m3, 6 Appearance grey metallic Atomic properties Atomic weight 92. ... Organic chemistry is the scientific study of the structure, properties, composition, reactions, and synthesis of organic compounds. ... In chemistry, a Lewis acid is any acid that can accept a pair of electrons and form a coordinate covalent bond, after the American chemist Gilbert Lewis. ... An alkene is an unsaturated hydrocarbon containing at least one carbon-carbon double bond. ... The Diels-Alder reaction is an organic chemical reaction (specifically, a cycloaddition) between a conjugated diene and a substituted alkene (commonly termed the dienophile) to form a substituted cyclohexene system. ... Pyrrolidine is a nearly colorless liquid pyrrole to which four hydrogen atoms have been added. ... In chemistry, a nucleophile (literally nucleus lover) is a reagent which is attracted to centres of positive charge. ... Benzophenone, also known as diphenylmethanone, phenyl ketone, diphenyl ketone, or benzoylbenzene. ... Indole is an aromatic heterocyclic organic compound. ...

External links

• MSDS http://www.chemexper.com [2]
• MSDS http://www.acros.be [3]

A material safety data sheet or MSDS is a form containing data regarding the properties of a particular substance. ... A material safety data sheet or MSDS is a form containing data regarding the properties of a particular substance. ...

References

• ^[4] Studies on the Niobium Pentachloride-Mediated Nucleophilic Additions to an Enantiopure Cyclic N-acyliminium Ion Derived from (S)-malic acid Carlos Kleber Z. Andrade,a, Rafael O. Rochaa, Dennis Russowskyb and Marla N. Godoy J. Braz. Chem. Soc., Vol. 16, No. 3B, 535-539, 2005. Online Article open access publication