P‑Directed Borylation of Phenols

Internal borylation occurs upon activation of aryl di-isopropylphosphinite boranes with HNTf₂ to give heterocyclic intermediates that can be reductively quenched to afford <b>6</b> or treated with KHF₂ to give the phenolic potassium aryl trifluoroborate salts <b>10</b>. The latter salts are useful for Pd-catalyzed coupling with aryl iodides under Molander conditions, provided that precautions are taken to remove the KNTf₂ byproduct from the preceding KHF₂ step

P‑Directed Borylation of Phenols

Internal borylation occurs upon activation of aryl di-isopropylphosphinite boranes with HNTf₂ to give heterocyclic intermediates that can be reductively quenched to afford <b>6</b> or treated with KHF₂ to give the phenolic potassium aryl trifluoroborate salts <b>10</b>. The latter salts are useful for Pd-catalyzed coupling with aryl iodides under Molander conditions, provided that precautions are taken to remove the KNTf₂ byproduct from the preceding KHF₂ step

Selective Pinacol-Coupling Reaction using a Continuous Flow System

The first continuous flow pinacol coupling reaction of carbonyl compounds was successfully achieved within only 2 min during a single pass through a cartridge filled with zinc(0). The optimized method allowed the efficient production of gram-scale value-added compounds with high productivity. The developed methodology is efficient for aromatic or α,β-unsaturated aldehydes but gives moderate results for more stable acetophenone derivatives. Moreover, the flow method displayed better results in terms of yield and selectivity in comparison to the corresponding batch methodology

Toward the Sustainable Synthesis of Biosourced Divinylglycol from Glycerol

Two high yielding protocols for the dehydration of glycerol to acrolein have been designed using strong Brönsted acid immobilized on silica gels. Acrolein is obtained with yield ranging from 91 to 95% in organic solvent or under solvent free conditions. The optimized solventless protocol has been then adapted for the direct formation of divinylglycol from glycerol. Neo-formed acrolein is directly coupled to divinylglycol by a double addition process giving 72% of the target divinylglycol in 1 h at a 10 g scale. This process could be referred as a two-chamber reactor with no accumulation of acrolein. Moreover, the reaction rate can be monitored by the rate of glycerol addition, which allows securing the whole system