36681-68-2

Upstream product

• 104-88-1 4-chlorobenzaldehyde 
• 513-81-5 2,3-dimethyl-buta-1,3-diene 

Relevant academic research and scientific papers

Scandium(III) Perfluorooctanesulfonate [Sc(OPf)3] : A Novel Catalyst for the Hetero Diels-Alder Reaction of Aldehydes with Non-Activated Dienes

Scandium(III) perfluorooctanesulfonate [scandium(III) perflate, Sc(OPf)3] was prepared from either scandium(III) chloride or oxide and perfluorooctanesulfonic acid. The perflate thus obtained acts as a novel Lewis acid catalyst for the intermolecular hetero Diels-Alder reaction of aldehydes with non-activated dienes under mild conditions. The characteristic features of the catalyst include (i) low hygroscopicity, (ii) ease of handling, and (iii) robustness for the recycling use.

AlCl3 catalyzed oxa-Diels-Alder reaction of aromatic aldehydes with simple dienes

A highly regioselective and diastereoselective oxa-Diels-Alder reaction catalyzed by AlCl3 has been developed. This reaction is efficient and characterized by good functional group compatibility, F, Cl, CN, NO2, OMe and thiophenyl groups are tolerated. A Lewis acid catalyzed concerted cycloaddition mechanism is proposed based on the results.

Nanoporous iron(III) porphyrin frameworks: an efficient catalyst for [4+2] cycloaddition reactions of unactivated aldehydes with a diene

The one pot conversion of several unactivated aldehydes with a diene to their corresponding [4+2] cycloaddition products has been studied using newly synthesized nanoporous iron(iii) porphyrin frameworks as catalysts. The heterogeneous catalysts have been synthesized from 5,10,15,20-tetrakis(4-cyanophenyl)porphyrinato iron(iii) chloride (PFe·X) with the help of Pinnar type synthesis. The catalytic activity of the monomeric catalyst (PFe·X) vs. that of the new nanoporous catalysts (1·X) where X = Cl-, BF4-etc. in the reaction of dienes and aldehydes were then compared. The structure of the catalysts was investigated using different characterization techniques including Fourier transform infrared spectroscopy (FT-IR), CHN, atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM) and the BET surface area which was measured via a physisorption study of N2 at 77 K. The reaction parameters determining yield, including the quantity of the catalyst and the solvent, were optimized to afford the hetero Diels-Alder product efficiently. It was observed that the nanoporous catalysts (1·X) were much superior to the monomeric (PFe·X) catalysts at giving selective products in high yields. Secondly, the new catalysts remained active for at least 8 cycles without any observable decay in their catalytic ability. Attempts are made to rationalize the results by considering the nature of X and the BET surface area of the 1·X catalysts.

Carbocation Catalysis: Oxa-Diels-Alder Reactions of Unactivated Aldehydes and Simple Dienes

The versatility of the trityl cation (TrBF4) as a highly efficient Lewis acid organocatalyst is demonstrated in the oxa-Diels-Alder reaction of various unactivated aromatic and aliphatic aldehydes and simple unactivated dienes, such as isoprene and 2,3-dimethylbutadiene. The transformation proceeds smoothly to give 3,6-dihydropyrane adducts in high to moderate yields with catalyst loadings down to 1.0 mol-% under mild reaction conditions. In contrast to most previously reported strategies, this protocol does not require substrate functional group activation, neither by electron-deficient aldehydes (2-oxo aldehydes) or electron-rich dienes (methoxy or amino-butadiene).

Hetero-Diels-Alder reaction of aromatic aldehydes catalyzed by titanium tetrachloride: Computational and experimental results

Computational calculations of the hetero-Diels-Alder (HDA) reactions of benzaldehyde with 2,3-dimethyl-1,3-butadiene (DMB) catalyzed by BF3, EtAlCl2 or TiCl4 at the density functional theory (DFT) (B3LYP/6-31G(d,p)) level

Cationic iron(III) porphyrin-catalyzed [4 + 2] cycloaddition of unactivated aldehydes with simple dienes

Cationic iron(III) porphyrin was found to be an efficient catalyst for the highly chemoselective hetero-Diels-Alder-type reaction of aldehydes with 1,3-dienes. The catalyzed process did not require the use of electron-deficient aldehydes such as glyoxylic acid derivatives or activated electron-rich 1,3-dienes such as Danishefsky's diene and Rawal's diene. The high functional group tolerance and robustness of the catalyst were demonstrated. Further, the potential utility of the catalyst was demonstrated by performing the cycloaddition in the presence of water and by carrying out cycloaddition of an unactivated ketone such as cyclohexanone with a diene.

Montmorillonite clay-catalyzed hetero-Diels-Alder reaction of 2,3-dimethyl-1,3-butadiene with benzaldehydes

Montmorillonite K10 clay was found to catalyze the hetero-Diels-Alder reaction of 2,3-dimethyl-1,3-butadiene with o-anisaldehyde and other benzaldehyde derivatives; a transition state involving chelation of the clay's metal ions with the dienophile's heteroatoms is proposed.