Current Organic Chemistry - Volume 15, Issue 11, 2011

Covalent pseudohalides (Scheme 1) are versatile tools in various chemical transformations and are widely used in various fields of chemistry as building blocks for synthesizing polymers, precursors, biologically active materials, and natural products. They occur in nature and smaller derivatives have been detected in the interstellar medium. Pseudohalides have a rich chemistry with a long and fascinating history, whic Read More

This review is devoted to organic selenocyanates. In the first part, the preparation of these compounds is reported. Organic selenocyanates have been synthesized by reaction of substrates with potassium selenocyanate, selenium diselenocyanate, diselenocyanate or selenium dicyanate. The reactions of selenenyl halides with cyanide ions or selenolates with cyanogen bromide are also efficient. In the second part, the physicoc Read More

Covalent cyanates are important species in preparative chemistry and widely used as synthetic reagents and building blocks for polymers. Covalent fulminates are hardly studied so far. This review focuses on the synthesis, spectroscopy, structural properties, and synthetic applications of cyanates, X-O-C≡ N, and fulminates, X-O-N+≡ C-, where the X substituent group is covalently linked to the oxygen atom.

Silicon and germanium azides are versatile tools in organic synthesis and widely used for various organic transformations e.g. as nucleophiles, 1,3-dipolarophiles, and azide-group transfer agents. This review article focuses on synthesis, spectroscopy, structural properties, and synthetic applications of silicon and germanium azides.

Small covalent nitrile oxides are important transient species in organic synthesis and widely used especially for dipolar cycloaddition reactions. Due to their instability, their isolation and characterization are challenging. This review focuses on the generation, spectroscopy, structural properties, and synthetic application of small nitrile oxides, XCNO, where the X substituent group is smaller than five atoms, viz. X= hydrogen, halog Read More

Nitrile sulfides, X-C≡N→S, are important transient species in organic synthesis and widely used for dipolar cycloaddition reactions. Nitrile selenides have the potential to become important dipolarophiles in preparative chemistry, however, their chemistry is largely unexplored. This review article focuses on generation, spectroscopic identification, structure, and synthetic applications of nitrile sulfides and nitrile selenides.

Hetero-substituted isocyanates and isothiocyanates RX-NCY (X = R2N, RO, or RS; Y = O or S) and the isomeric cyanates RX-OCN, thiocyanates RX-SCN, nitrile oxides RX-CNO, and nitrile sulfides RX-CNS are highly reactive compounds, often transient at room temperature. The chemistry of these compounds is reviewed. A number of rearrangement reactions is described, particularly [3,3]- sigmatropic shifts, e.g. PhX-NCY → o-HX-C Read More

Nitrogen heterocycles are widespread in nature and their applications in bioactive pharmaceuticals, agrochemicals and functional materials are well known. A number of protocols have been developed for their syntheses. This review article covers an updated (published during 2005-2008) summary of transition metal-catalyzed approaches for the syntheses of five- and six-membered ring heterocycles with one nitrogen ato Read More

The usual synthesis of phosphinates involving the reaction of phosphinic chlorides with alcohols or phenols in the presence of a tertiary amine in an apolar solvent cannot be regarded as “green” and requires expensive P-reagents. We have found that in certain cases phosphinic acids can be esterified by simple alcohols under microwave (MW) conditions. Hence, cyclic phosphinic acids, such as 1-hydroxy-3- and 2-phospholene Read More

The reaction of 3,4-dihydro-β-carboline derivatives with 1,3-dipoles, such as a nitrile imine and a nitrile oxide led to triazolopyridoindole and oxadiazolo-pyridoindole derivatives, respectively, that are novel synthetic alkaloids. Stereostructure, stability and further reactions of the pyridoindoles were also investigated. The oxadiazolo-pyridoindoles underwent reaction with a second unit of nitrile oxide to afford the co Read More

This account is focused on highlighting the recent advances on synthetically-useful organic reactions employing siliconcentered radicals in water, and presenting new reactions in water, mediated by silyl radicals. In doing so, several types of organic radical transformations will be discussed, such as reduction of organic halides utilizing non toxic organosilane reducing agents in water, transformation of azides into amines, synt Read More

With the development of separation materials, more and more complex natural products with poly-stereogenic centers are obtained. However, due to small quantity of the isolated compounds, or no crystal formed, or complex 2D NMR correlation signals, absolute configuration identification for these compounds becomes difficult. Now, computational methods provide researchers many benefits in structural determinations for ch Read More

Molecular imprinted polymers (MIPs) are being developed as a powerful way to achieve molecular recognition via the template- directed synthesis which results in the formation of specific cavities complementary to the molecule in shape and chemical functionality. One of the most successful application areas of MIPs is chromatographic sorbents. The use of MIPs sorbents in capillary electrochromatography (CEC) is attractive i Read More