Stabilised sulfur ylides are synthetically appealing compounds, which reactivity under Brønsted acid catalysis has been poorly explored. Herein, we report a new catalyst- and substrate- dependent chemodivergent reaction between stabilised salicylaldehydes, leading to the (suprising) formation of 2H-chromenes or dihydrobenzofurans products. Particular attention was set on unusual mechanisms invo...

Grignard reagents (R-Mg-X) are commercial carbon nucleophiles commonly used in organic synthesis, but their stability becomes a limitation for the least-reactive electrophiles. A bulky magnesium anilide additive (in purple) generates new organometallic reagent (R−Mg-NHAr) situ that boosts nucleophilicity and selectivity of ligand green). In Research Article by A. Mendoza co-workers (DOI: 10.100...

Allylboronic esters react readily with carbonyls and imines (π-electrophiles), but are unreactive toward a range of other electrophiles. By addition of an aryllithium, the corresponding allylboronate complexes display enhanced nucleophilicity, enabling addition to a range of electrophiles (tropylium, benzodithiolylium, activated pyridines, Eschenmoser's salt, Togni's reagent, Selectfluor, diiso...

Weinreb amidation of ethyl 4-oxo-3,4-dihydroquinazoline-2-carboxylate with aromatic amines provides a significantly improved route to anilide-type key intermediates for the synthesis of the anticancer alkaloid, luotonin A, and new A-ring-modified derivatives thereof. This method has advantages concerning overall yield, brevity, and versatility with regard to the aromatic amine component, even i...

Compared to conventional molecular solvents, the ionic liquid [b-3C-im][NTf(2)] was found to promote transimination reactions with up to ∼100-fold rate enhancement. This rate effect observed at ambient temperature might be explained by the fact that the ionic liquid displays weak Lewis acidity with very low, if any, nucleophilicity and its imidazolium cation is expected to interact by associati...

We have investigated the oxidative behaviour of natural compounds such as methyl abietate (1), farnesyl acetate (2), α-ionone (3), β-ionone (4), methyl linolelaidate (5), methyl linolenate (6) and bergamottin (7) with the oxidant system methyltrioxo-rhenium/ H2O2/pyridine. The reactions, performed in CH2Cl2/H2O at 25 °C, have shown good regio- and stereoselectivity. The oxidation products were ...

The very low basicity and nucleophilicity of the phosphorus donor in phosphinines can be drastically increased by introducing strongly σ-donating Me3Si substituents to aromatic heterocycle. highest gas-phase was found for 2,3,5,6-tetrakis(trimethylsilyl)phosphinine, which is even more basic gas phase than pyridine. This finding led first quantitative synthesis a phosphinine selenide treating re...

The cleavage of silicon–hydrogen bonds to generate silicon-containing metal complexes has played an essential role in the preparation organosilicon compounds. Herein, we report reaction cyclopentadienone iridium complex 1 with hydrosilanes afford hydroxycyclopentadienyl silyl 4 via umpolung Si–H bond. nucleophilicity Ir–Si bond resulting was demonstrated allyl halide and ethyl acrylate. Further...