90959-08-3

Upstream product

• 100-52-7 benzaldehyde 
• 89-51-0 Homophthalic acid 
• 703-59-3 homophthalic anhydride 

Downstream Products

• 56260-42-5 (3R,4R)-Methyl 1-oxo-3-phenylisochroman-4-carboxylate 
• 56260-42-5 trans-4-methoxycarbonyl-3-phenyl-3,4-dihydroisocoumarin 
• 41169-10-2 2-(1-carboxy-2-phenylvinyl)benzoic acid 
• 33608-93-4 (E)-2,3-dihydro-3-phenylmethylene-1H-isoindol-1-one 
• 40523-32-8 3-(phenylmethylene)isoindol-1-one 

Relevant academic research and scientific papers

A novel dual organocatalyst for the asymmetric pinder reaction and a mechanistic proposal consistent with the isoinversion effect thereof

In general, the Pinder reaction concerns the reaction between an enolisable anhydride and an aldehyde proceeding initially through a Knoevenagel reaction followed by the ring closing process generating lactones with at least two chiral centers. These scaffolds are frequently present in natural products and synthetic bioactive molecules, hence it has attracted intense interest in organic synthesis and medicinal chemistry, particularly with respect to controlling the diastereo-and enantioselectivity. To the best of our knowledge, there has been only one attempt prior to this work towards the development of a catalytic enantioselective Pinder reaction. In our approach, we designed, synthesized, and tested dual chiral organocatalysts by combining BIMAH amines, (2‐(α‐ (alkyl)methanamine)‐1H‐benzimidazoles, and a Lewis acid motif, such as squaramides, ureas and thioureas. The optimum catalyst was the derivative of isopropyl BIMAH bearing a bis(3,5‐ trifluoromethyl) thiourea, which afforded the Pinder products from various aromatic aldehydes with diastereomeric ratio >98:2 and enatioselectivity up to 92 ee%. Interestingly, the enantioselectivity of this catalyzed process is increased at higher concentrations and exhibits an isoinversion effect, namely an inverted ?U? shaped dependency with respect to the temperature. Mechanistically, these features, point to a transition state involving an entropy‐favored heterodimer interaction between a catalyst/anhydride and a catalyst/aldehyde complex when all other processes leading to this are much faster in comparison above the isoinversion temperature.

Catalytic Asymmetric Cycloadditions between Aldehydes and Enolizable Anhydrides: Cis-Selective Dihydroisocoumarin Formation

In the presence of a trityl-substituted cinchona alkaloid-based catalyst, homophthalic, aryl succinic, and glutaconic anhydride derivatives reacted with aromatic and aliphatic aldehydes to produce cis-lactones in up to 90:10 dr and 99% ee. A DFT study has shown how the catalyst is uniquely able to bring about the opposite sense of diastereocontrol to that usually observed.

A catalytic asymmetric reaction involving enolizable anhydrides

In the presence of a highly efficient novel bifunctional organocatalyst at low loadings under mild conditions, enolizable homophthalic anhydrides can be added to a range of aromatic and aliphatic aldehydes to give dihydroisocoumarins, with excellent yields and diastereo-and enantiocontrol (up to 99% ee).

cis/trans-Isochromanones. DMAP induced cycloaddition of homophthalic anhydride and aldehydes

Homophthalic anhydride (1) reacts with wide variety of aromatic aldehydes, in the presence of chloroform and DMAP (N,N-dimethyl-4-amino-pyridine) at room temperature, to give in high yields cis- and trans-1-oxo-isochroman-4- carboxylic acids. Under these

Cycloaddition of homophthalic anhydrides with aldehydes and ketones: A route to 3,4-dihydroisocoumarin-4-carboxylic acid derivatives

Homophthalic anhydride reacts with benzaldehyde, in the presence of boron trifluoride - diethyl ether complex to give the cycloadduct 3-phenyl- 3,4-dihydroisocoumarin-4-carboxylic acid in good to excellent yield. Under these conditions, we did not observe

Strong base-induced cycloaddition reaction of homophthalic anhydride with aldehydes

The reaction of homophthalic anhydride (1) and aldehydes in the presence of a strong base was studied. Reaction of 1 and benzaldehyde in the presence of NaH in anhydrous tetrahydrofuran (THF) at low temperature (0°C-room temperature) followed by treatment