Letters in Organic Chemistry - Volume 7, Issue 8, 2010

Environmentally-friendly (green) chemistry is in focus these days. One of the twelve principles of green chemistry recommends the application of catalysts making possible selective synthesis under milder conditions. The six articles of this minireview issue describe novel complexes and/or the use of such compounds in synthesis. The first paper covers the synthesis and application of -SCS- pincer complexes incorporating thioca Read More

The extension in the chemistry of pincer-type complexes over the last decade has led to the creation and detailed investigation of those bearing a wide range of donor coordinating groups fixed on a number of central cores. This review covers the synthesis, reactivity, application in catalysis, and photooptical properties of symmetrical SES-pincer complexes (E = C, N, P) having thiocarbamoyl or thiophosphoryl coordination gro Read More

In the past decade, novel types of carbene complexes have been developed, for which the two substituents at C are P(V) moieties. Different strategies have been devised, relying on the use of the isolable geminal dianion, the monoanion or the neutral ligands. In the two latter cases, the deprotonation (mono and double respectively) in the coordination sphere, yields the desired carbene complex. In this review, such carb Read More

5- and 6-Membered P-heterocycles including phosphines (1H-phospholes, 3-phospholenes, phospholanes, dihydro- and tetrahydrophosphinines), phosphinites (dibenzo[c.e][1,2]oxaphosphorines) and phosphonites (benzo[1,3,2]dioxaphospholanes), as well as, 3-P-substituted species 3-diphenylphosphino-1,2,3,6-tetrahydrophosphinine or 1,2,3,4,5,6-hexahydrophosphinine derivatives are surveyed as potential monodenta Read More

In this minireview, the most important recent results in homogeneous catalytic aminocarbonylations, achieved by the authors during the last 5 years, are surveyed. The widely used palladium catalyst precursors, the in situ formation of palladium(0) catalysts, as well as the reaction mechanism of the palladium-catalysed carbonylations based on the application of carbon monoxide are discussed. The aminocarbonylat Read More

Various carbonyl cobalt complexes were found to be suitable catalyst precursors for the selective transformation of aliphatic primer diazoalkanes into the corresponding ketenes. Stable ketene such as (trimethylsilyl)ketene was isolated from the reaction mixtures in high yield. Highly reactive ketene such as ethoxycarbonylketene was isolated as its dimer or in the presence of proper reactants as in situ addition products in high Read More

One of the practical applications of sugar-based crown ethers involves their use as chiral catalysts in enantioselective phase transfer reactions. Chiral crown ethers incorporating various monosaccharide units in the macrocyclic structure are reviewed which may be efficient enantioselective catalysts in certain asymmetric reactions, such as Michael addition, epoxidation of α,β-enones and Darzens condensation.

The synthesis of C21-C26 fragment of superstolide A, starting from D-glucose diacetonide, involving regioselective ring opening of epoxide by Grignard reagent and regioselective stereospecefic hydroboration oxidation has been described.

A highly efficient route to substituted furans from readily available 5-hydroxymethyl-substituted Δ2- isoxazolines is described. The transformation involves sequential reduction/hydrolysis/cyclocondensation in a one-pot reaction using iron as reducing agent under mild conditions.

An efficient, metal-free and chemo-selective Friedel-Crafts allylation of indoles in 2,2,2-trifluoroethanol (TFE) is developed. A possible mechanism has also been discussed to explain the observed competitive pathways in this reaction system.