Aldol Condensation of Cycloalkanones with Aromatic Aldehydes Catalysed with TiCl3(SO3CF3)

Abstract

Efficient cross-aldol condensation of cyclopentanone, cyclohexanone and 1-indanone with various aromatic aldehydes is catalysed with TiCl 3 SO 3 CF 3 at room temperature in excellent yields.

Silica sulfuric acid as an efficient and reusable reagent for crossed-aldol condensation of ketones with aromatic aldehydes under solvent-free conditions

“…The results are summarized in the Table 1. The reactions were completed within 2-3.5 h and high yields of α,α'-bis(substituted benzylidene and cinnamylidene) cyclopentanones and cyclohexanones were obtained (entries [1][2][3][4][5][6][7][8][9][10][11][12]. Under these conditions, no self-condensation of the starting materials was J. Braz.…”

“…6,7 Anhydrous RuCl 3 and TiCl 3 (SO 3 CF 3 ) have also been used for this purpose under solvent-free conditions. 8,9 The use of expensive and toxic reagents, long reaction times, low yields, and formation of a mixture of products are among the drawbacks of the reported methods. Recently, more attention has been paid to the synthesis of α,α'-bis(substituted benzylidene)cycloalkanones.…”

Synthesis of some 4-bromo-1-naphthyl chalcones using silica-sulfuric acid reagent under solvent free conditions

“…14 Anhydrous RuCl 3 and TiCl 3 (SO 3 CF 3 ) have also been applied for aldol condensation reactions under solvent-free conditions. 15 Now more attention has been paid to synthesis of acyclic and cyclic chalcones by chemists. 16 Balakrishna Kalluraya 17 et al reported that they obtained 60-70% yield of sydnone chalcones under solvent free condition by aldol condensation reaction by grinding of ketones and aldehydes with sodium hydroxide.…”

A Highly Efficient Method for Synthesis of Bisarylmethylidenes of Cyclic Ketones in [BMIm]Cl/NaOH System as New and Recyclable Catalyst

“…Subsequently, improved by utilization of gentle catalysts methodologies have been reported. The most successful catalyst used there was: different organometallic complexes 14 34 , Ti(OR) 4 35 etc. However, in the most cases, process suffers from high cost and difficult catalyst preparation, uses of toxic or stoichiometric amounts of catalyst, hydrolyzing of catalyst in the presence of water which may result in the aldol-condensation reactions, not recyclability of that catalysts, long reaction time or high reaction temperature, unwanted side reactions, involving complicated or tedious purification operations, generation of large amount of wastes, low yields and peculiar reaction conditions.…”