203111-49-3Relevant academic research and scientific papers
Titanium(IV) chloride and oxy-compounds promoted Baylis-Hillman reaction
Shi, Min,Jiang, Jian-Kang,Cui, Shi-Cong
, p. 7343 - 7347 (2001)
The Baylis-Hillman reaction of aryl aldehydes with α,β-unsaturated ketones in the presence of titanium(IV) chloride can be promoted by oxy-compounds at room temperature, although they are not as effective as amines, chalcogenides, or quaternary ammonium salts. The oxy-compounds can be simple alcohols, ethers, and ketones. For aryl aldehydes having a strong electron-withdrawing group on the phenyl ring such as nitrobenzaldehyde or p-trifluoromethylbenzaldehyde, the chlorinated compound 1 is obtained as the major product. However, for other aryl aldehydes, the elimination compound 3 was formed predominantly. We also found that TiCl4·2THF or TiCl4·2Et2O complex is very effective for this reaction to give the chlorinated products in high yields at low temperature. A plausible mechanism is proposed.
Titanium(IV) chloride and the amine-promoted Baylis-Hillman reaction
Shi, Min,Jiang, Jian-Kang,Feng, Yan-Shu
, p. 2397 - 2400 (2000)
(equation presented) In the Baylis-Hillman reaction, we found that, when the reactions of arylaldehydes with methyl vinyl ketone were carried out at -20°C using a catalytic amount of amine as a Lewis base in the presence of titanium(IV) chloride, the chl
Amendment in titanium(IV) chloride and chalcogenide-promoted Baylis- Hillman reaction of aldehydes with α,β-unsaturated ketones
Shi, Min,Jiang, Jian-Kang
, p. 4793 - 4797 (2000)
The Baylis-Hillman reaction can be drastically affected by the reaction temperature and Lewis base. When the reaction was carried out at -20°C using methyl sulfide as a Lewis base in the presence of titanium(IV) chloride, the chlorinated compound 1 was
Aminocatalysis of the Baylis-Hillman reaction: an important solvent effect
Davies, Huw J.,Ruda, Antionio M.,Tomkinson, Nicholas C.O.
, p. 1461 - 1464 (2007)
Examination of the aminocatalytic Baylis-Hillman reaction in the presence of proline and imidazole has revealed that water plays a crucial role in the acceleration of the reaction, allowing for excellent yields of the adduct between methyl vinyl ketone an
The crystallographic structure of 4-hydroxy-3-methylene-4-(p-nitrophenyl)butan-2-one
Shi, Min,Jiang, Jian-Kang
, p. 1295 - 1297 (1999)
The crystallographic structure of 4-hydroxy-3-methylene-4-(p-nitrophenyl)butan-2-one 1 is disclosed by x-ray analysis. It crystallized in the space group C2/c (#15) with a = 19.958(4), b = 10.486(3), c = 15.009(3) A, β = 137.553(6)°, V = 2120.0(9)A°3
Amino acid-peptide-catalyzed enantioselective Morita-Baylis-Hillman reactions
Vasbinder, Melissa M.,Imbriglio, Jason E.,Miller, Scott J.
, p. 11450 - 11459 (2006)
Peptide-based catalysts in the presence of proline as co-catalyst have been found to catalyze the enantioselective ketone-based Morita-Baylis-Hillman reaction. The co-catalyst combination has afforded catalysis where enantioselectivities of up to 81% have
A 2D Coordination Network That Detects Nitro Explosives in Water, Catalyzes Baylis-Hillman Reactions, and Undergoes Unusual 2D→3D Single-Crystal to Single-Crystal Transformation
Sharma, Vivekanand,De, Dinesh,Pal, Sanchari,Saha, Prithwidip,Bharadwaj, Parimal K.
, p. 8847 - 8855 (2017)
The solvothermal reaction of Zn(NO3)2·6H2O and a linear dicarboxylate ligand H2L, in the presence of urotropine in N,N′-dimethylformamide (DMF), gives rise to a new porous two-dimensional (2D) coordination netwo
Supported N-alkylimidazole-decorated dendrons as heterogeneous catalysts for the Baylis-Hillman reaction
Goren, Kerem,Portnoy, Moshe
, p. 1965 - 1967 (2010)
The Baylis-Hillman reaction between methyl vinyl ketone and aromatic aldehydes, catalyzed by N-alkylated imidazoles immobilized on polystyrene via dipolar cycloaddition, esterification or nucleophilic substitution, exhibits a remarkable positive dendritic
Heterogeneous Baylis-Hillman using a polystyrene-bound 4-(N-benzyl-N- methylamino)pyridine as reusable catalyst
Corma, Avelino,Garcia, Hermenegildo,Leyva, Antonio
, p. 2806 - 2807 (2003)
An insoluble Merrifield type resin having 4-aminopyridine units is a suitable and reusable heterogeneous catalyst for the Baylis-Hillman coupling of aromatic aldehydes and α,β-unsaturated ketones.
Chemoselectivity Improvement via Partial Shielding of an Imidazole Active Site in Branched/Dendritic Homogeneous Catalysts of the Baylis–Hillman Reaction
Karabline-Kuks, Jeny,Ramesh, Palakuri,Portnoy, Moshe
, p. 3541 - 3554 (2016)
While comparing analogous polystyrene-supported and homogeneous catalysts for the Baylis–Hillman reaction, we hypothesized that the hydrophobic envelopment of the imidazole catalytic sites of the former is responsible for the significantly better chemoselectivity exhibited by the heterogeneous catalysts compared to their homogeneous counterparts. In order to test this hypothesis, we prepared a series of branched/dendritic homogeneous catalysts, with an imidazole active site near the focal point and flexible tails of various lengths and polarities, capable of providing partial shielding of this site. The design of the catalysts was based on a 5-hydroxyisophthalate scaffold, and they were prepared through a number of multistep synthetic pathways. The comparison of the catalysts under a variety of conditions in a model Baylis–Hillman reaction demonstrated that long hydrophobic tales enhance the chemoselectivity parameter of the catalysis, while reducing the rate of the consumption of the substrates, and that the chemoselectivity is further improved by the presence of a free phenolic moiety in the vicinity of the catalytic imidazole unit. Moreover, in second-generation catalysts, the peripheral long tails could be either hydrophobic or polar, since the dendritic inner backbone itself presumably partially provides the necessary isolation of the catalytic site. Thus, experimental results support our hypothesis. (Figure presented.).
