Tjøstil Vlaar

• Vrije Universiteit Amsterdam

Cyanohydrins are versatile intermediates toward valuable organic compounds like α-hydroxy carboxylic acids, α-amino acids, and β-amino alcohols. Numerous protocols are available for synthesis of (O-protected) cyanohydrins, but all procedures invariably rely on the use of toxic cyanide sources. A novel cyanide-free synthesis of O-trityl protected cy...

Multiple applications of isothioureas as fine chemicals (or their precursors) are known, but a general sustainable method for their synthesis was hitherto unavailable. We report a novel general approach towards S-alkyl and S-aryl isothioureas through a copper(I)-catalyzed three-component reaction between amines, isocyanides, and thiosulfonates. The...

Multiple applications of isothioureas as fine chemicals (or their precursors) are known, but a general sustainable method for their synthesis was hitherto unavailable. We report a novel general approach towards S-alkyl and S-aryl isothioureas through a copper(I)-catalyzed three-component reaction between amines, isocyanides, and thiosulfonates. The...

We report the palladium(II)‐catalyzed aerobic oxidative coupling of isocyanides with various (2‐aminophenyl)azoles using air as the stoichiometric oxidant. A diverse range of medicinally valuable azolo[ c ]quinazolines was obtained by this new approach. magnified image

An unprecedented aerobic oxidative Pd-catalyzed imidoylative coupling of two C–H fragments furnishing medicinally valuable 4-aminoquinolines is reported. Optimization studies are described and several analogs were successfully prepared.

A new synthetic approach to 4-aminopyrido[2,3-d]pyrimidines and 4-aminopyrido[3,2-d]pyrimidines based on palladium-catalyzed reaction of isocyanides with readily available N-(bromopyridyl)amidines is reported. The target heterocycles were obtained in generally good to excellent yield. For the two regioisomeric pyrimidopyrimidines, we compared our a...

Isocyanides have been important building blocks in organic synthesis since the discovery of the Ugi reaction and related isocyanide-based multicomponent reactions. In the past decade isocyanides have found a new application as versatile C1 building blocks in palladium catalysis. Palladium-catalyzed reactions involving isocyanide insertion offer a v...

Isocyanides have emerged as valuable C1 building blocks in palladium catalysis. Their potential has, however, mainly been exploited for the synthesis of amidines and amidine-containing heterocycles. To illustrate the broader applicability of isocyanides, we have recently developed a novel oxidative coupling of diamines and isocyanides furnishing va...

Seit der Entdeckung der Ugi-Reaktion und ähnlicher Isocyanid- basierter Mehrkomponentenreaktionen sind Isocyanide wichtige Bausteine für die organische Synthese. In den letzten zehn Jahren fanden Isocyanide als vielseitige C1-Bausteine in der Palladiumkatalyse eine neue Anwendung. Palladiumkatalysierte Reaktionen, die unter Isocyanidinsertion ablau...

4-Aminophthalazin-1(2H)-ones (APOs) are underexplored heterocyclic compounds with promising and diverse biological activities. The classical synthesis of these compounds is tedious and does not allow the regioselective introduction of substituents. Here, we present our full studies on the Pd-catalyzed cross-coupling of substituted o-(pseudo)haloben...

Heterocycles containing a guanidine moiety are of great importance in medicinal chemistry (Scheme 1).[1] As a result, several methods for the synthesis of these "privileged scaffolds" have been reported.[2, 3] Classical approaches, such as the addition of diamines to isothiocyanates followed by condensation and the coupling of diamines with cyanoge...

Palladium-catalyzed cross-coupling of a wide range of substituted o-(pseudo)halobenzoates and hydrazines with isocyanide insertion followed by lactamization efficiently affords 4-aminophthalazin-1(2H)-ones that are difficult to obtain regioselectively by classical methods.

The importance of palladium-catalyzed cross coupling reactions in contemporary organic synthesis is undisputed and underlined by the Nobel Prize for Chemistry in 2010. In addition to the highly efficient cross coupling reactions for single CC bond construction, palladium-catalyzed cascade processes involving multiple bond formations have emerged in...