Andrea Porcheddu

One-Pot Synthesis of Amides from Aldehydes and Amines via C–H Bond Activation

A one-pot synthesis of amides from aldheydes with N-chloroamines, prepared in situ from amines, has been developed. Both aliphatic and aromatic aldehydes and many types of mono- and disubstituted amines are tolerant in this transformation. This cross-coupling reaction appears simple and convenient, has a wide substrate scope and makes use of cheap, abundant, and easily available reagents.

Some Recent Approaches to the Synthesis of 2-Substituted Benzofurans

In their structural multiplicity and in the extent to which they occur in nature the derivatives of benzofuran are significantly lesser than the isoelectronic analogue indoles. However, these heterocyclic compounds show a variety of pharmacological properties, and change of their structure offers a high degree of diversity that has proven useful for the search of new therapeutic agents. The broad spectrum of pharmacological activity in individual benzofurans indicates that this series of compounds is of an undoubted interest. From this point of view, synthetic methods may be of very useful aid in the production of specific structures characterized by given pharmacological qualities. Moreover from a drug discovery perspective, synthesis of chiral functionalized substituted benzofurans could be more interesting because they might constitute starting materials for the production of biologically active compounds. Taking into account the actual tendency directed toward the development of enantiomerically pure drugs, indeed there is a limited number of papers related to the preparation of enantiomers of benzofuran containing compounds, likely because of difficulties in their preparation with conventional methods. In this context, new approaches seem to expand the potentiality of the synthesis of substituted benzofurans, providing also convenient routes to enantiopure 2-substituted benzofurans.

Iron-catalysed oxidative amidation of alcohols with amines

A new iron-catalysed oxidative amidation of differently substituted benzylic alcohols with mono- and di-substituted amines was developed.

From alcohols to indoles: a tandem Ru catalyzed hydrogen-transfer Fischer indole synthesis.

In a new version of the Fischer indole synthesis, primary and secondary alcohols have been catalytically oxidized in the presence of phenylhydrazines and protic or Lewis acids to give the corresponding indoles. The overall reaction can be accomplished in one step, and the use of alcohols instead of aldehyes or ketones as starting materials has several advantages in terms of a large selection of reagents, easy handling, and safety of the process.

Microwave-Promoted Selective Mono-N-Alkylation of Anilines with Tertiary Amines by Heterogeneous Catalysis

A palladium-catalyzed N-alkylation of anilines with tertiary amines that occurs under heterogeneous transfer-hydrogenation conditions has been developed. This protocol of transamination, which uses a relatively cheap and easily recyclable heterogeneous catalyst, can be efficiently applied to different substrates and is suitable for large-scale preparations.

Synthesis of α , β -unsaturated aldehydes based on a one-pot phase-switch dehydrogenative cross-coupling of primary alcohols

An efficient one-pot ruthenium-catalyzed hydrogen-transfer strategy for a direct access to α,β-unsaturated aldehydes has been developed. The employment of enolates prepared in situ from alcohols avoided handling unstable aldehydes and provided a very appealing route to different cinnamaldehydes substituted in position 2. A silica-grafted amine was used as phase-switch tag leading to a selective one-pot process in favor of cross-dehydrogenative coupling products.

New pyrazole containing bicarboxylic α-amino acids: mimics of the cis amide bond

A series of novel optically active α-amino acids, containing a pyrazole ring, which can be regarded as building blocks for peptidomimetics, have been prepared starting from readily available α-amino acids. The synthetic strategy employed allows the regio- and stereoselective preparation of 1,3- or 1,5-substituted pyrazolyl rings. The pyrazole containing peptidomimetics can be considered as analogues of peptides with a cis amide bond.

New 1,3,5-triazine derivatives as templates for the homogeneous phase synthesis of chemical libraries

Abstract The synthesis of tri-functionalized orthogonally protected CRAB templates based on the triazine skeleton are described together with some protocols for the preparation of families of diversomers using a parallel synthesis approach.

Parallel Synthesis of Trisubstituted Formamidines: A Facile and Versatile Procedure

A focused library of formamidines having several diversity points has been prepared. The use of isocyanate resin as scavenger may offer several practical advantages over conventional procedures, such as the ease of workup and availability. The technique described herein was performed in a parallel synthesis format. The whole protocol has potential use in high throughput synthesis for the preparation and purification of libraries of unsymmetrical formamidines containing sets of different aliphatic substituents.

A fast and efficient one-pot microwave assisted synthesis of variously di-substituted 1,2,4-oxadiazoles

A one-pot two-step microwave assisted synthesis of variously disubstituted 1,2,4-oxadiazoles from carboxylic acids and amidoximes is reported. This methodology is characterized by short reaction times, is versatile, robust and high-yielding and allows for the preparation of heterocycles with a stereocenter with 100% enantiomeric purity.