The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the involvement of electronically excited states, generated upon absorption of photons. This produces transient reactive intermediates and significantly alters the reactivity of a chemical compound. The input of energy provided by light thus offers a means to produce strained and unique target compounds that cannot be assembled using thermal protocols. This review aims at highlighting photochemical transformations as a tool for rapidly accessing structurally and stereochemically diverse scaffolds. Synthetic designs based on photochemical transformations have the potential to afford complex polycyclic carbon skeletons with impressive efficiency, which are of high value in total synthesis.

Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis

Carbon−Carbon Bond Formations Involving Organochromium(III) Reagents

Direct and rapid heating by microwave irradiation in combination with sealed vessel processing in many cases enables reactions to be carried out in a fraction of the time generally required using conventional conditions. This makes microwave chemistry an ideal tool for rapid reaction scouting and optimization of conditions, allowing very rapid progress through hypotheses–experiment–results iterations. The speed at which multiple variations of reaction conditions can be performed allows a morning discussion of “What should we try?” to become an after-lunch discussion of “What were the results” Not surprisingly, therefore, many scientists both in academia and industry have turned to microwave synthesis as a front-line methodology for their projects. In this review, more than 220 published examples of microwave-assisted synthetic organic transformations from the 2004 to 2008 literature are discussed. An additional ca. 500 reaction schemes are presented in the Electronic Supplementary Material, providing the reader with an overall number of ca. 930 references in this fast-moving and exciting field.

Controlled microwave heating in modern organic synthesis: highlights from the 2004–2008 literature

Progress in the development of asymmetric Heck couplings of arenes and acyclic olefins has been limited by a tenuous understanding of the factors that dictate selectivity in migratory insertion and β-hydride elimination. On the basis of key mechanistic insight recently garnered in the exploration of selective Heck reactions, we report here an enantioselective variant that delivers β-, γ-, or δ-aryl carbonyl products from acyclic alkenol substrates. The catalyst system imparts notable regioselectivity during migratory insertion and promotes the migration of the alkene's unsaturation toward the alcohol to ultimately form the ketone product. The reaction uses aryldiazonium salts as the arene source, yields enantiomeric products from opposite starting alkene configurations, and uses a readily accessible ligand. The racemic nature of the alkenol substrate does not bias the enantioselection.

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Enantioselective Heck Arylations of Acyclic Alkenyl Alcohols Using a Redox-Relay Strategy

This review is focused on the analysis of current data on new methods of alkenylation of arenes and heteroarenes with alkynes by transition metal catalyzed reactions, Bronsted/Lewis acid promoted transformations, and others. The synthetic potential, scope, limitations, and mechanistic problems of the alkenylation reactions are discussed. The insertion of an alkenyl group into aromatic and heteroaromatic rings by inter- or intramolecular ways provides a synthetic route to derivatives of styrene, stilbene, chalcone, cinnamic acid, various fused carbo- and heterocycles, etc.

Alkenylation of Arenes and Heteroarenes with Alkynes.

Organic thiocyanates are important synthetic intermediates to access valuable sulfur-containing compounds. In this review the different methods for their preparation and their synthetic applications will be presented. The literature of the last 15 years will be covered, highlighting selected recent advances in the chemistry of this class of compounds. We hope to offer chemists the tools to have a good grasp of this singular functionality and open the door to further progress in this chemistry.

Recent advances in the chemistry of organic thiocyanates

Cyclocarbopalladation: Sequential Cyclization and C−H Activation/Stille Cross-Coupling in the Pd-5-Exo-Dig Reaction

A New Pd-Catalyzed Cascade Reaction for the Synthesis of Strained Aromatic Polycycles

A 4‐exo‐dig Cyclocarbopalladation/8π Electrocyclization Cascade: Expeditious Access to the Tricyclic Core Structures of the Ophiobolins and Aleurodiscal

Jean Suffert

Papers

Recent advances in the chemistry of organic thiocyanates

Cyclocarbopalladation: Sequential Cyclization and C−H Activation/Stille Cross-Coupling in the Pd-5-Exo-Dig Reaction

A New Pd-Catalyzed Cascade Reaction for the Synthesis of Strained Aromatic Polycycles

A 4‐exo‐dig Cyclocarbopalladation/8π Electrocyclization Cascade: Expeditious Access to the Tricyclic Core Structures of the Ophiobolins and Aleurodiscal

An Easy and Useful Preparation of Propynyllithium from (Z/E)-1-Bromopropene