Efficient Pd-catalyzed allene synthesis from alkynes and aryl bromides through an intramolecular base-assisted deprotonation (iBAD) mechanism.

An optimized ligand-controlled palladium-catalyzed allene synthesis starting from alkynes and aryl bromides giving rise to allene products in a simple and direct manner is described. The methodology is performed in an inter- and intramolecular fashion with unprecedented scope and excellent yields. Based on mechanistic investigations and on DFT calculations, the role played by the carboxylic additive (i.

Asymmetric transformations via C-C bond cleavage.

Catalytic asymmetric transformations operating by carbon-carbon (C-C) bonds cleavages have emerged as intriguing strategies to access transient organometallic species from different reaction pathways. The reactions and the applicable substrate range have expanded considerably over the last decade. This overview covers the main developments in this field.

Highly enantioselective rhodium(I)-catalyzed activation of enantiotopic cyclobutanone C-C bonds.

The selective functionalization of carbon-carbon σ bonds is a synthetic strategy that offers uncommon retrosynthetic disconnections. Despite progress in C-C activation and its great importance, the development of asymmetric reactions lags behind. Rhodium(I)-catalyzed selective oxidative additions into enantiotopic C-C bonds in cyclobutanones are reported.

Synthesis and reactivity of furoquinolines bearing an external methylene-bond: access to reduced and spirocyclic structures.

A family of furoquinolines were efficiently obtained through a tandem acetalization/cycloisomerization process catalyzed by (5 mol%) silver imidazolate polymer and triphenylphosphine, and diversity was brought by the use of 7 different alcohol groups. From these furoquinolines, 3 examples of reduced derivatives could be obtained (d.r.

Silver-catalyzed furoquinolines synthesis: from nitrogen effects to the use of silver imidazolate polymer as a new and robust silver catalyst.

Silver-catalyzed tandem acetalization and cycloisomerization reactions were found to lead to various furoquinolines, and a nitrogen effect was noticed for AgOTf reactivity, since the cyclization mode switched from 6-endo-dig to 5-exo-dig; from these observations silver imidazolate polymer is proposed as a stable silver catalyst.