One of the current challenges faced by the scientific community is to reconcile the pressing need to develop efficient and sophisticated chemical processes, to access functionalized and complex molecules, with the limited ability of our planet to absorb pollution. A solution consists in the design of new processes to avoid the use of scarce precious metals, using cheap organic promoters and reagents of low toxicity, high stability to air and moisture, and working in green solvents under mild and less hazardous reaction conditions. In this direction, recently our group reported a mild and convenient protocol for the first direct α-hydroxylation of α-substituted malonates, β-ketoesters, and β-ketoamides via the Rubottom oxidation by cheap and stable oxidant MMPP, which proceeds at room temperature in EtOH as green solvent (Scheme 1). One-pot and tandem methodologies are highly attractive considering their advantages in minimizing waste production while avoiding purification or separation of intermediates. Over the years, our group has been focusing on the development of organocatalytic one-pot methodologies for the stereoselective synthesis of differently functionalized heterocyclic scaffolds. In particular, considering the prominent role played by nitrogen-containing heterocycles in the fields of natural products, market drugs, agrochemicals and dyes, we recently paid attention to the design of one-pot and cascade processes to easily access novel N-unprotected-tetrasubstituted trans-2-pyrrolines 3 and amidines 4 starting from commercially available reagents and exploiting fundamental consecutive organic reactions (5 or 4 steps) in benign solvents. In a similar way, the first enantioselective synthesis of popular drugs benzothiazepines 2 has been realized, minimizing the number of operations despite the number of transformations involved, paving the way for the concise preparation of the antidepressant drug (R)-(-)-thiazesim in an extremely easy and more sustainable way.
XXVII CONGRESSO NAZIONALE DELLA SOCIETÀ CHIMICA ITALIANA
sara meninno
2021
Abstract
One of the current challenges faced by the scientific community is to reconcile the pressing need to develop efficient and sophisticated chemical processes, to access functionalized and complex molecules, with the limited ability of our planet to absorb pollution. A solution consists in the design of new processes to avoid the use of scarce precious metals, using cheap organic promoters and reagents of low toxicity, high stability to air and moisture, and working in green solvents under mild and less hazardous reaction conditions. In this direction, recently our group reported a mild and convenient protocol for the first direct α-hydroxylation of α-substituted malonates, β-ketoesters, and β-ketoamides via the Rubottom oxidation by cheap and stable oxidant MMPP, which proceeds at room temperature in EtOH as green solvent (Scheme 1). One-pot and tandem methodologies are highly attractive considering their advantages in minimizing waste production while avoiding purification or separation of intermediates. Over the years, our group has been focusing on the development of organocatalytic one-pot methodologies for the stereoselective synthesis of differently functionalized heterocyclic scaffolds. In particular, considering the prominent role played by nitrogen-containing heterocycles in the fields of natural products, market drugs, agrochemicals and dyes, we recently paid attention to the design of one-pot and cascade processes to easily access novel N-unprotected-tetrasubstituted trans-2-pyrrolines 3 and amidines 4 starting from commercially available reagents and exploiting fundamental consecutive organic reactions (5 or 4 steps) in benign solvents. In a similar way, the first enantioselective synthesis of popular drugs benzothiazepines 2 has been realized, minimizing the number of operations despite the number of transformations involved, paving the way for the concise preparation of the antidepressant drug (R)-(-)-thiazesim in an extremely easy and more sustainable way.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.