10329-06-3Relevant academic research and scientific papers
Solvent-free selective cross-aldol condensation of ketones with aromatic aldehydes efficiently catalyzed by a reusable supported acidic ionic liquid
Davoodnia, Abolghasem,Yassaghi, Ghazaleh
, p. 1950 - 1957 (2012)
A newly prepared catalyst consisting of acidic ionic liquid 1-(4-sulfonic acid) butylpyridinium hydrogen sulfate supported on silica was used to catalyze the cross-aldol condensation of ketones with aromatic aldehydes under solvent-free conditions. The highly active and selective catalyst gave good to excellent yields of the desired cross-aldol products without the occurrence of any self-condensation reactions. Reaction times were short, the procedure and work-up were simple, and no volatile or hazardous organic solvents were necessary. Moreover, the catalyst could be reused at least four times with only a slight reduction in activity.
Synthesis, characterization, and crystal structures of α, α'-bis(substituted-benzylidene)cycloalkanone derivatives by nano-TiO2/HOAc
Tabrizian, Elham,Amoozadeh, Ali,Rahmani, Salman,Salehi, Mehdi,Kubicki, Maciej
, p. 531 - 544 (2016)
A new and economical synthesis of α, α'-bis(substituted-benzylidene)cycloalkanones has been achieved by the reaction of cycloalkanones with different aromatic aldehydes using nano-TiO2/acetic acid as a catalyst in ethanol under reflux conditions with excellent yields. Five new products and three new single crystal structures are reported.
Novel synthesis and crystal structures of two a, a0-bis-substituted benzylidene cyclohexanones: 2,6-Bis-2-nitro(benzylidene)cyclohexanone and 2,6-Bis-4-methyl(benzylidene)cyclohexanone
Amoozadeh, Ali,Rahmani, Salman,Dutkiewicz, Grzegorz,Salehi, Mehdi,Nemati, Firouzeh,Kubicki, Maciej
, p. 1305 - 1309 (2011)
Two a,a0-bis-substituted benzylidene cycloalkanones have been synthesized in presence of SnCl4 and their crystal structures have been determined by means of X-ray diffraction. The bis(para-methyl) derivative, 2,6-bis- 4-methyl(benzylidene)cyclo
Sulfonated PEG-intercalated montmorillonite [(Mt/PEG)-SO3H] as efficient and ecofriendly nanocatalyst for synthesis of α,α′-bis(substituted benzylidene)cycloalkanones
Dalil Heirati, Seyedeh Zahra,Shirini, Farhad,Fallah Shojaei, Abdollah
, p. 6167 - 6186 (2017/10/05)
(Montmorillonite/PEG)-SO3H nanocomposite was successfully prepared for the first time and introduced as a solid acid nanocatalyst. Initially, polyethylene glycol (PEG) polymeric chains were intercalated into interlayer spaces of montmorillonite. The resulting Mt/PEG nanocomposite with good mechanical and thermal stability was chosen as a useful clay mineral/polymer support for further modification with chlorosulfonic acid. Structural characterization of (Mt/PEG)-SO3H was carried out using X-ray diffraction (XRD) analysis, Brunauer–Emmett–Teller (BET) measurements, Barrett–Joyner–Halenda (BJH) analysis, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier-transform infrared (FT-IR) spectroscopy. The results showed that PEG chains were intercalated into the clay mineral layers and that the Mt/PEG nanocomposite was successfully sulfonated. (Mt/PEG)-SO3H nanocomposite exhibited high specific surface area and good stability up to around 150?°C, showing excellent potential for application as a recyclable nanocatalyst. (Mt/PEG)-SO3H was used as an efficient and ecofriendly solid acid nanocatalyst for preparation of α,α′-bis(substituted benzylidene)cycloalkanones under solvent-free conditions, leading to many interesting findings. The excellent conversion values confirm that the catalyst has strong and sufficient acidic sites, which are responsible for its catalytic performance. The reaction under mild conditions (room temperature) with excellent yield, catalyst recyclability (up to ten times), and simple work-up procedure represent useful advantages of (Mt/PEG)-SO3H for catalysis. Moreover, the reaction could be scaled up to 10 and 15?mmol scales.
Synthesis of air-stable mixed bis-carboxylate titanocene complexes and their catalytic behaviors in cross-aldol and Mannich reactions
Wang, Jing,Chen, Xi,Wang, Xiu,Zhang, Wei-Qiang,Sun, Hua-Ming,Zhang, Guo-Fang,Wu, Ya,Gao, Zi-Wei
, p. 731 - 738 (2016/09/13)
Tunable organometallic Lewis acid catalysts were developed by combining salicylic acid (H2-Sal) with benzoic acid (H-Ben), 4-fluorobenzoic acid (H-BenF) and 3-thiophenic acid (H-Th), as coligands for mixed bis-carboxylate titanocene complexes. Three air-stable complexes [Cp2Ti(η1-HSal)(η1-Ben)] (1), [Cp2Ti(η1-HSal)(η1-BenF)] (2) and [Cp2Ti[η1-HSal][(η1-Th)] (3) were prepared in high yields by the reaction of salicylato titanocene chelate with carboxylate ligands. The mixed bis-carboxylate titanocene complexes were fully characterized by physicochemical and spectroscopic methods. Single-crystal X-ray diffraction studies revealed Ti–O(H-Sal) bond distances in 1, 2 and 3 of 1.972(3), 1.9245(18) and 1.912(5)??, respectively, while the bond distances involving the coligands of 1, 2 and 3 are 1.908(3)?? (Ti–OBen), 1.9296(19)?? (Ti–OBenF) and 1.945(5)?? (Ti–OTh), respectively. These bis-carboxylate titanocene complexes showed satisfactory activities and selectivities in Mannich and cross-aldol reactions. Notably, complex 3 bearing the labile thiophene carboxylate ligand gave high yields with a diastereomer ratio (d.r.) as high as 1:99 for the direct Mannich reactions of benzaldehyde, cyclohexanone and aniline. In cross-aldol reaction of benzaldehyde and cyclohexanone, 1 and 2 successfully catalyzed the formation of double-aldol products in up to 99?% yield.
Fast, facile and convenient synthesis of α, α-bis(substituted- arylidene) cycloalkanones: An improved protocol
Mahdavinia, Gholam Hossein,Mirzazadeh, Maryam
experimental part, p. 49 - 54 (2012/06/01)
Commercially available potassium hydroxide (KOH), a simple base, was found to be a catalyst for tandem cross-aldol condensation between cyclic ketones and aromatic aldehydes leading to a fast and easy synthesis of α,α-bis (substituted-arylidene) cycloalkanones in the shortest times of all previous methods. The reaction of aryl aldehydes with five and six-membered cyclic ketones afforded excellent yields after few seconds in most cases. The reaction conditions were compatible with various electron withdrawing and electron donating substituents, e.g. Cl, F, NO2, OMe, Me and NMe2.
Poly(ethylene)glycol/AlCl3 as a Green and Reusable System in the Synthesis of α,α′'-bis(substituted-benzylidene) Cycloalkanones
Amoozadeh, Ali,Rahmani, Salman,Nemati, Firouzeh
experimental part, p. 72 - 74 (2011/06/11)
Aluminum chloride has been found to be a highly efficient catalyst for the aldol condensation of aldehydes and cycloketones in poly(ethylene)glycol 400 at room temperature. The reaction is very fast, clean and environmentally benign for the synthesis of a variety of α,α′'-bis(substituted- benzylidene) cycloalkanones.
A facile synthesis of α,α′-bis(substituted-benzylidene)-cycloalkanones and substituted-benzylidene heteroaromatics: utility of NaOAc as a catalyst for aldol-type reaction
Motiur Rahman,Jeong, Byeong-Seon,Kim, Dong Hyeon,Park, Jung Ki,Lee, Eung Seok,Jahng, Yurngdong
, p. 2426 - 2431 (2007/10/03)
Utility of NaOAc in glacial HOAc as a catalyst for aldol-type condensation reactions was examined. Reactions of cycloalkanones and selected heteroaromatics with various aldehydes in the presence of NaOAc in glacial HOAc provided α,α′-bis(substituted-benzylidene)cycloalkanones and substituted-benzylidene heteroaromatics, respectively, in good yields.
