A Palladium Iodide-Catalyzed Carbonylative Approach to Functionalized Pyrrole Derivatives

A Central-to-Axial Chirality Conversion Strategy for the Synthesis of C-N Axially Chiral N-Arylpyrroles

We present a central-to-axial chirality conversion strategy for the construction of C-N axially chiral N-arylpyrroles via a gold(I)-catalyzed 5-endo-dig cyclization/dehydration cascade from amino acid derivatives. The reaction exhibits high efficiency on the central-to-axial chirality conversion. Density functional theory calculations suggest that the stereospecificity during the central-to-axial chirality conversion lies in the stability of the conformations of the amino alcohol and the corresponding low barrier transition state.

PdI2-Based Catalysis for Carbonylation Reactions: A Personal Account

In this account, we review our efforts in the field of carbonylation reactions promoted by palladium iodide-based catalysts, which have proven to be particularly efficient in diverse kinds of carbonylation processes (oxidative carbonylations as well as additive and substitutive carbonylations). Particularly in the case of oxidative carbonylations, more emphasis has been given to the most recent results and applications.

3-Heterosubstituted Benzofurans from Hydroxyphenyl Propargyl Alcohols via ortho-Quinone Methide through a Metal-/Catalyst-Free Conjugate Addition/Oxy-Cyclization

A facile route to 3-sulfonylated and 3-(1-benzotriazolyl)-benzofurans is achieved from readily available o-hydroxyphenyl propargyl alcohols (o-HPPAs) and bench-top sodium sulfonylates and benzotriazoles with no assistance of any reagent or catalyst. Bifunctional o-quinone methides (o-QMs) were the putative reaction intermediates ensued from dehydration of o-HPPA. Our study revealed that the o-QM was so choosy in selection of the nucleophiles for the key Michael addition reaction.

C(sp3)–H dehydrogenation and C(sp2)–H alkoxy carbonylation of inactivated cyclic amines towards functionalized N-heterocycles

A novel and efficient synthesis of tetrahydropyridine-, dihydropyrrole-, and tetrahydroazepine-3-carboxylates via cascade reactions of cyclic amines with CO and alcohols is presented. To our knowledge, this should be the first example in which functionalized N-heterocycles were prepared through Pd-catalyzed C(sp³)–H dehydrogenation and C(sp²)–H carbonylation of cyclic amines.

Recent advances in the synthesis of pyrroles by multicomponent reactions

Pyrrole is one of the most important one-ring heterocycles. The ready availability of suitably substituted and functionalized pyrrole derivatives is essential for the progress of many branches of science, including biology and materials science. Access to this key heterocycle by multicomponent routes is particularly attractive in terms of synthetic efficiency, and also from the environmental point of view. We update here our previous review on this topic by describing the progress made in this area in the period between mid-2009 and the end of 2013.

One-pot synthesis of alkyl pyrrole-2-carboxylates starting from β-nitroacrylates and primary amines

Herein, we present a new, efficient, one-pot synthesis of pyrrole-2-carboxylate derivatives starting from ketal-functionalized β-nitroacrylates in combination with primary amines under acidic heterogeneous conditions.

A mild and efficient AgSbF6-catalyzed synthesis of fully substituted pyrroles through a sequential propargylation/amination/cycloisomerization reaction

Development of an efficient synthesis of fully substituted pyrroles via a sequential as a catalyst. The propargylation/amination/cycloisomerization was accomplished using AgSbF₆ one-pot three-component reaction of propargylic alcohols, 1,3-dicarbonyl compounds, and primary amines proceeds at a mild temperature, which prevents the formation of furan by-product. The reaction was also successfully applied to the more basic aliphatic amines with the addition of 1.1 eq. of acetic acid.