Synthesis of 3-alkylideneisoindolinones and isoindolones by a Horner–Wadsworth–Emmons reaction

Three-component synthesis, utilization and biological activity of phosphinoyl-functionalized isoindolinones

A new method for the synthesis of 3-oxoisoindolin-1-ylphosphine oxides bearing same or different substituents on the phosphorus atom is described. The one-pot three-component reaction of 2-formylbenzoic acid, primary amines and achiral or P-stereogenic secondary phosphine oxides provided the target compounds under catalyst-free, mild conditions and for short reaction times. The deoxygenation of a 3-oxoisoindolin-1-ylphosphine oxide was also studied, and the phosphine obtained could be converted to a sulphide and to a platinum complex. The crystal structures of a selected phosphine oxide and the corresponding platinum species were investigated by X-ray diffraction analysis. The biological activity, such as in vitro cytotoxicity on different cell lines and antibacterial activity of the 3-oxoisoindolin-1-ylphosphine oxides was also investigated. Based on the IC50 values obtained, several derivatives showed moderate activity against the HL-60 cell line and two compounds containing 3,5-dimethylphenyl groups on the phosphorus atom showed promising activity against Bacillus subtilis bacteria.

Study on the Microwave-Assisted Batch and Continuous Flow Synthesis of N-Alkyl-Isoindolin-1-One-3-Phosphonates by a Special Kabachnik-Fields Condensation

A simple and efficient microwave (MW)-assisted method was elaborated for the catalyst-free synthesis of isoindolin-1-one-3-phosphonates by the three-component condensation of 2-formylbenzoic acid, aliphatic primary amines and various dialkyl phosphites. The batch and the continuous flow reactions were optimized in respect of the temperature, the reaction time and the molar ratio of the starting materials. To evaluate the potential of MW irradiation, comparative thermal experiments were also carried out. In order to obtain “real time” information about the condensation, the special Kabachnik–Fields reaction of 2-formylbenzoic acid, butylamine and diethyl phosphite was monitored by in situ FT-IR spectroscopy. The novel title compounds could be prepared in high yields at low temperature under a short reaction time. A suitable method could also be developed for the preparation of the isoindolin-1-one-3-phosphonates at a “few g” scale by using a continuous flow MW reactor.

The photodecarboxylative addition of carboxylates to phthalimides as a key-step in the synthesis of biologically active 3-arylmethylene-2,3-dihydro-1H-isoindolin-1-ones

The synthesis of various 3-arylmethylene-2,3-dihydro-1H-isoindolin-1-ones was realized following a simple three-step process. The protocol utilized the photodecarboxylative addition of readily available carboxylates to N-(bromoalkyl)phthalimides as a versatile and efficient key step. The initially obtained hydroxyphthalimidines were readily converted to the desired N-diaminoalkylated 3-arylmethylene-2,3-dihydro-1H-isoindolin-1-ones via acid-catalyzed dehydration and subsequent nucleophilic substitution with the corresponding secondary amines. The procedure was successfully applied to the synthesis of known local anesthetics (AL-12, AL-12B and AL-5) in their neutral forms.

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given.

Expeditious synthesis of (±)-diethyl 2-alkyl- and 2-aryl-(3-oxoisoindolin-1-yl)phosphonates catalysed by OSU-6

An efficient synthesis of (±)-diethyl 2-alkyl- and 2-aryl-(3-oxoisoindolin-1-yl)phosphonates is reported via condensation of 2-carboxybenzaldehyde with an amine and triethyl phosphite using OSU-6 as the catalyst.