Raimondo Maggi

A revision of the Biginelli reaction under solid acid catalysis. Solvent-free synthesis of dihydropyrimidines over montmorillonite KSF

Abstract The reaction of aldehydes, β-dicarbonyl compounds and urea (Biginelli reaction) has been performed over solid acid catalysis, under solventless conditions or in water affording dihydropyrimidines in good yield and selectivity. Dihydropyrimidines4 were obtained in good yield and selectivity by reacting aldehydes, β-dicarbonyl compounds and ureas in the presence of montmorillonite KSF under solventless conditions. Download : Download full-size image

Cycloaddition of CO2 to epoxides over both homogeneous and silica-supported guanidine catalysts

Abstract The synthesis of cyclic carbonates by CO 2 insertion into epoxides catalysed by both homogeneous MTBD and TDB supported on MCM-41 mesoporous silica is reported.

Three-component process for the synthesis of 2-amino-2-chromenes in aqueous media

Abstract The reaction of an aldehyde, malononitrile and a phenol in water at reflux in the presence of cetyltrimethylammonium chloride (CTACl) as catalyst affords a one-pot synthesis of 2-amino-2-chromenes.

Selected syntheses of ureas through phosgenesubstitutes

Ureas have been traditionally synthesised by methodologies mainly based on the use of dangerous reagents such as phosgene and isocyanates. In the last few years, however, these reagents have been increasingly substituted by cleaner alternative and inherently safer compounds since the goal of the modern environmentally friendly synthetic chemistry is the development and optimisation of reaction conditions to reduce or eliminate the use and production of hazardous materials while maximising energy usage. Thus different and sometimes sophisticated phosgene substitutes such as bis(4-nitrophenyl)carbonate, triphosgene, di-tert-butyl dicarbonate, 1,1-carbonylbisimidazole, 1,1-carbonylbisbenzotriazole, S,S-dimethyldithiocarbonate and trihaloacetylchlorides have been utilised as safer reagents which can be stored and handled without special precautions. Moreover, the large scale production of urea derivatives has been more conveniently performed by using simpler and cheaper raw materials such as CO and CO2 in catalytic processes, avoiding production of large amounts of saline by-products which represent the main constituent of chemical waste.

Zeolite HSZ-360 as a new reusable catalyst for the direct acetylation of alcohols and phenols under solventless conditions

Abstract Alcohols and phenols were efficiently acylated with acetic anhydride without solvent over zeolite HSZ-360. The catalyst can be reused with no activity loss.

Clean synthesis in water. Part 2: Uncatalysed condensation reaction of Meldrum's acid and aldehydes

Abstract The environment-friendly condensation of Meldrums acid and aromatic, heteroaromatic and hindered aliphatic aldehydes is performed carrying out the reaction in water at 75°C for 2 h, avoiding the addition of any catalyst.

Clean synthesis in water: uncatalysed preparation of ylidenemalononitriles

A simple, efficient and environment-friendly procedure is developed for the condensation of malononitrile with aromatic, heteroaromatic and aliphatic aldehydes in water. The ylidenemalononitriles 3 are synthesised in high yields (84–98%) and selectivities (87–98%) in distilled water at 65 °C for 1 h, avoiding the addition of any catalyst.

Supported organic catalysts: synthesis of (E)-nitrostyrenes from nitroalkanes and aromatic aldehydes over propylamine supported on MCM-41 silica as a reusable catalyst

Abstract MCM-41-supported propylamine showed high catalytic efficiency in the nitroaldol condensation between nitroalkanes and aromatic aldehydes.

Update 1 of: Use of Solid Catalysts in Friedel−Crafts Acylation Reactions

Update 1 of: Use of Solid Catalysts in Friedel Crafts Acylation Reactions Giovanni Sartori* and Raimondo Maggi Clean Synthetic Methodologies Group and National Interuniversity Consortium “Chemistry for Environment” (INCA), Unit PR2, Dipartimento di Chimica Organica e Industriale, Universit a degli Studi di Parma, Parco Area delle Scienze 17A, I-43100 Parma, Italy This is a Chemical Reviews Perennial Review. The root paper of this title was published in Chem. Rev. 2006, 106 (3), 1077 1104, DOI: 10.1021/cr040695c; Published (Web) February 14, 2006. Updates to the text appear in red type.

Solvent free synthesis and deprotection of 1,1-diacetates over a commercially available zeolite Y as a reusable catalyst

Abstract Chemoselective synthesis and deprotection of 1,1-diacetates have been performed in good yields and in the absence of any solvent by zeolite HSZ-360 as a new reusable catalyst.