Current Organic Chemistry - Volume 15, Issue 13, 2011

With the publication of “Fundamentals in Organocatalysis. Past, Present and Future” in Current Organic Chemistry, our fascinating adventure gets to the end. As reflected in recent publications in top journals within the field of Organic Chemistry, the search for novel highly efficient catalytic processes is an active challenge that allows rapid access to complex molecular skeletons. In this respect, during the last decade, metal-f Read More

The umpolung bezoin-type and Stetter-type reactions are valuable synthetic strategies to furnish an ample number of important compounds and asymmetric building blocks. Biocatalysis is contributing to this field with several thiamine-dependent lyases, enzymes that are able to catalyze these reactions under mild reaction conditions with high yields and enantioselectivities. Furthermore, recent developments in that field have le Read More

In the last few years, the new era of organocatalysis opened up an effective and efficient way to high yielding metal free, enantio- and diastereoselective reactions leading to six-membered heterocycles. This review provides an overview of the current achievements in the organocatalytic synthesis of these crucial building blocks. Ranging from hetero-Diels-Alder to cycloadditions, from one step cyclizations t Read More

Chiral compounds, bearing closely positioned Bronsted base and Bronsted acid groups, are usefully exploited as bifunctional organocatalysts in a wide array of asymmetric processes. These compounds operate via the generation of a more active nucleophilic species through general base catalysis, whereas the electrophile is activated via hydrogen bonding by the Bronsted acidic group. In this review, we illustrate the achie Read More

Activation of imines by hydrogen bonding is a very powerful way of promoting the synthesis of a variety of nitrogencontaining compounds of interest. Such a useful approach typically involves mild reaction conditions, simple experimental operations and metal-free reagents. The present review focuses on the recent development of new organocatalytic methods involving imines and related compounds as substrates in wh Read More

Organocatalytic, asymmetric Mannich reactions giving β3-amino acid derivatives have been reviewed. The Mannich-type addition of an acetate anion to an imine represents in fact one of the most direct routes to this particular class of β-amino acids. However, due to the low acidity of simple acetates, synthetic equivalents of acetate anions had to be used. These include preformed enolates (silylketeneacetals), carbonylic com Read More

Chiral phosphoric acids derived from axially chiral biaryls and analogous chiral Bronsted acids have emerged as an attractive and widely applicable class of enantioselective organocatalysts for a variety of organic transformations. In this account article, we review our recent achievements and related works in the development of enantioselective carbon-carbon bond forming reactions using these axially chiral phosphoric acids Read More

Organocatalyzed reactions can often be advantageously performed in non-traditional reaction media. Use of ionic liquids, water or brine often leads to improved yields and selectivities of organocatalytic transformations. In terms of energy source, organocatalyzed reactions can be significantly accelerated by microwave irradiation, ultrasound or high pressure. Reactions without solvent and performed in ball mills are Read More

Lewis and Bronsted base catalysis are rapidly growing areas in organocatalysis. Numerous binaphthyl-derived chiral base catalysts has been developed over the last years. Recent progress in the chiral Lewis and Bronsted base catalysis has been reviewed with a focus being placed on mono-functional catalysts, including primary and secondary diamines, guanidines, phosphines and phosphineoxides; bi- and multifunctio Read More

The synthesis of complex active molecules has afforded the search for new methods and new processes in organic synthesis. In this context, organic metal free catalysis has appeared as a powerful tool being complementary to metal catalysis in the field of asymmetric synthesis. The success of this methodology has been increasing in the last decade and the research for new organocatalytic systems as well as new ap Read More