Facile Synthesis of Isochromanones and Isoquinolones by AuCl3 Catalyzed Cascade Triggered by an Internal Nucleophile

Rhodium-catalyzed synthesis of substituted isoquinolones via a selective decarbonylation/alkyne insertion cascade of phthalimides

A rhodium-catalyzed decarbonylation/alkyne insertion cascade of phthalimides has been established. The reaction can be carried out in an operationally simple manner and provides expedient access to a series of isoquinolones in moderate to good yields. This reaction proceeded through a sequential decarbonylation/alkyne insertion/intramolecular annulation procedure and featured good functional group tolerance, ample substrate scope, and the construction of C-C and C-N bonds in one pot.

Palladium-catalysed stereoselective synthesis of 4-(diarylmethylidene)-3,4-dihydroisoquinolin-1(2H)-ones: expedient access to 4-substituted isoquinolin-1(2H)-ones and isoquinolines

Palladium-catalysed stereoselective synthesis of 4-(diarylmethylidene)-3,4-dihydroisoquinolin-1(2H)-ones and their straightforward transformations to 4-substituted isoquinolin-1(2H)-ones and isoquinolines are described.

AgOTf-catalyzed sequential synthesis of 4-isoquinolones via oxidative ring opening of aziridines and aza-Michael addition

An efficient AgOTf-catalyzed sequential reaction involving the oxidative ring-opening of aziridines by DMSO and aza-Michael addition has been developed. A series of 2,3-dihydro-4(1H)-isoquinolones were afforded in moderate to good yields by the formation of one new C[double bond, length as m-dash]O bond and one new C-N bond. The features of this sequential reaction include high bonding efficiency, use of a catalytic amount of catalysts, a broad substrate scope and mild conditions. This methodology provides a good choice for constructing the libraries of 2,3-dihydro-4(1H)-isoquinolones.

Gold-catalysed reactions of diynes

In this critical review the reactivity patterns observed with different types of diyne substrates in gold catalysis are discussed. Apart from the many examples from homogeneous catalysis, the few examples from heterogeneous gold catalysis are also included. With a proper arrangement of the two alkynes unique and exciting reactivity patterns like 1,3-carbonyl transpositions, carbene transfer reactions, cascade annulations, macrocyclisations or the formation of gold vinylidene intermediates are observed. These reactions are of interest for organic synthesis, for pharmaceutical and medicinal chemistry and for material science.

Gold(I) catalysed sequential dehydrative cyclisation/intermolecular [4 + 2] cycloaddition of alkynyldienols onto activated alkynes/alkenes: a facile route to substituted norbornadienes/norbornenes

One-pot synthesis of highly substituted norbornadienes/norbornenes via gold-catalysed dehydrative cyclisation of alkynyldienols, followed by intermolecular [4 + 2] cycloaddition of in situ generated cyclopentadiene and activated alkynes/alkenes is described. The precursors, alkynyldienols, are obtained via sequential Sonogashira cross-coupling of 3-bromoenals, alkyne addition and reduction. Yields of the enynals and multisubstituted norbornadienes in all the cases are good to excellent.

Gold(i)-catalysed [1,3] O→C rearrangement of allenyl ethers

Gold standard: a simple and rapid access to the α-substituted acryl aldehydes has been provided by developing a gold-catalysed [1,3] rearrangement of the allenyl ethers importantly with a record turnover frequency = 4600 h⁻¹ (at 0.05 mol% of the catalyst concentration) in homogeneous gold(i) catalysis.