Synthesis of Dipentaerythritol from Pentaerythritol under Acidic Conditions

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Oxidative nucleophilic substitution : transformation of alkylboronic derivatives.

International audienceAn efficient amidation reaction is described in this paper. Potassium alkyltrifluoroborate salts can be transforming to amides from nitriles in the presence of copper acetate and boron trifluoride. An extension of this reaction allowed the formation of amines, ethers, and C–C bond

Reduction of aromatic and aliphatic nitro groups to anilines and amines with hypophosphites associated with Pd/C

International audienceThe reduction of aromatic and aliphatic nitro groups to anilines and amines is performed with good yield and selectivity in short reaction times. A mixture of sodium hypophosphite and phosphinic acid is used in the presence of a heterogeneous catalyst 2.5 mol% of Pd/C (5%) in a biphasic water/2-MeTHF system

Solvent-Free Michael Addition to Non-protected 3-(2-Nitrovinyl)indole by Ultrasound Activation.

International audienceA variety of nucleophiles provided by activated methylenes have been added on 3-(2-nitrovinyl)-1H-indole in very good to excellent yields, under sonication and solvent-free conditions, using solid potassium carbonate or sodium acetate as a base. Direct synthesis avoiding preliminary NH protection is reported and exemplified to 15 molecules

Synthetic applications of hypophosphite derivatives in reduction.

International audienceThe development of new tools for the reduction of organic functions to reach high chemo- and stereo-selectivity is an important research domain. Although, aluminum and boron hydrides are commonly used, they suffer from environmentally and safety issues. In particular, at industrial scale, the search for more specific and efficient reagents with a lower ecological impact remains one of the main objectives of organic chemists. This review captures highlights from literature concerning phosphonic and phosphinic acid derivatives as reducing agents and evaluates their potential as alternatives, in particular to boron and aluminum hydrides

Metal-free electrophilic fluorination of alkyl trifluoroborates and boronic acids.

International audienceSecondary alkyl trifluoroborates undergo facile electrophilic fluorination under mild conditions to afford the corresponding benzylic fluorinated adducts in excellent yield

Biphasic Glycerol/2-MeTHF, Ruthenium-Catalysed Enantioselective Transfer Hydrogenation of Ketones Using Sodium Hypophosphite as Hydrogen Donor

International audienceSodium hypophosphite has been used as an efficient hydrogen donor in the transfer hydrogenation of aliphatic and aromatic ketones in the presence of [RuCl2(p-cymene)]2 and 2,2′-bipyridine in water. The corresponding alcohols were isolated in moderate to excellent yields (39–95 %). Good chemoselectivity was observed with ester, nitrile and halide functionalities in the ketones not being reduced. An enantioselective version of the reaction using [RuCl(p-cymene){(R,R)-TsDPEN}] as catalyst in a glycerol/2-MeTHF biphasic solvent mixture has been developed and allowed the reduction of (hetero)aromatic ketones with excellent chemo- and enantioselectivities (up to 97 % ee)

Synthetic applications of hypophosphite derivatives in reduction.

International audienceThe development of new tools for the reduction of organic functions to reach high chemo- and stereo-selectivity is an important research domain. Although, aluminum and boron hydrides are commonly used, they suffer from environmentally and safety issues. In particular, at industrial scale, the search for more specific and efficient reagents with a lower ecological impact remains one of the main objectives of organic chemists. This review captures highlights from literature concerning phosphonic and phosphinic acid derivatives as reducing agents and evaluates their potential as alternatives, in particular to boron and aluminum hydrides

Ritter-type amidation of alkylboron derivatives with nitriles

International audienceA mild and facile synthesis of amides from alkylboron compounds and nitriles promoted by copper acetate and BF3·OEt2 at room temperature is disclosed

12. La chimie verte

Ce qu’il est convenu d’appeler « chimie verte » ou « durable » ou « écologique » regroupe des concepts et des technologies ayant recours à des matières premières renouvelables. Cet ensemble a conduit à des pratiques industrielles et scientifiques très différentes de celles qui ont fait les immenses succès de la chimie du XXe siècle (amélioration et préservation de la vie) et parfois ses terribles conséquences (accidents, pollutions, contaminations…). La chimie, à la fois science et industrie,..