Ornelio Rosati

Ytterbium triflate promoted synthesis of 1,5-benzodiazepine derivatives

Abstract 2,3-Dihydro-1 H -1,5 benzodiazepines have been synthetized in very good yield in solvent-free conditions from o -phenylendiamine and ketones in the presence of Yb(OTf) 3 as catalyst. The method is applicable to both cyclic or acyclic ketones without significant differences.

Layered zirconium phosphate and phosphonate as heterogeneous catalyst in the preparation of pyrroles

Abstract Pyrroles may be prepared by condensation of alkyl and aryl amines and 1,4-diketones (Paal–Knorr reaction) under potassium exchanged layered Zirconium phosphate and zirconium sulfophenyl phosphonate catalyst in solvent free conditions.

Heterogeneous Catalysis in Trimethylsilylation of Alcohols and Phenols by Zirconium Sulfophenyl Phosphonate

Abstract Layered zirconium sulfophenyl phosphonate was found to be an efficient heterogeneous catalyst for the trimethylsilylation of alcohols and phenols.

Preparation and deprotection of 1,1-diacetates (acylals) using zirconium sulfophenyl phosphonate as catalyst

Layered zirconium sulfophenyl phosphonate was found to be an efficient heterogeneous catalyst for the preparation and deprotection of 1,1-diacetates.

Carbamate synthesis from amines and dimethyl carbonate under ytterbium triflate catalysis

A facile synthesis of carbamates from amines and dimethyl carbonate has been achieved using ytterbium triflate as catalyst.

Zirconium Sulfophenyl Phosphonate as a Heterogeneous Catalyst in the Preparation of β-Amino Alcohols from Epoxides

A convenient method for the ring opening of epoxides by aromatic amines, catalysed by zirconium sulfophenyl phosphonate in solvent-free conditions, is described.

Zirconium sulfophenyl phosphonate as a heterogeneous catalyst in tetrahydropyranylation of alcohols and phenols

Abstract Zirconium Sulfophenyl Phosphonate Zr(O 3 PCH 3 ) 1.2 (O 3 PC 6 H 4 SO 3 H) 0.8 was found to be an efficient heterogeneous catalyst for the tetrahydropyranylation of alcohols and phenols.

Efficient synthesis of cyanohydrin trimethylsilyl ethers via 1,2-chemoselective cyanosilylation of carbonyls

Here we report a sustainable protocol for the cyanosilylation of carbonyl compounds 1a–g and 3a–m using trimethylsilyl cyanide and triphenylphosphine supported on polystyrene as a catalyst under solvent-free conditions. It has been shown that a small amount of the catalyst allows the chemoselective 1,2-addition of trimethylsilyl cyanide to α,β-unsaturated carbonyls 1a–g (5 mol%) and to saturated carbonyls 3a–m (2 mol%). The preparation of cyanohydrin trimethylsilyl ethers 2a–g and 4a–m has been accomplished in good yields (72–99%) and very low E-factor values (5–10). Finally, efficiency has been further improved by setting two different flow procedures that have allowed us to perform the representative preparation of cyanohydrin trimethylsilyl ether 4a on a large scale and with the E-factor of 0.16 or 0.47 consisting in a reduction of 90 or 72% of waste compared to our batch conditions.

Heterogeneous catalysis in acetylation of alcohols and phenols promoted by zirconium sulfophenyl phosphonate.

Abstract Layered zirconium sulfophenyl phosphonate was found to be an efficient heterogeneous catalyst for the acetylation of alcohols and phenols.

Solvent-free chemoselective oxidation of thioethers and thiophenes by mechanical milling

Organosulphur compounds can be easily and selectively oxidized to sulfones using a small excess of Oxone(®) (1.6 eq.) under solventless mechanical milling conditions. This green procedure has been efficiently applied to a series of model compounds and to the desulphurization of medium/high sulphur content paraffins (up to 3000 mg kg(-1)).