Montmorillonite K10-Catalyzed Aza Diels-Alder Reaction of Danishefsky’s Diene with Aldimines, Generated in situ from Aliphatic Aldehydes and Amine, in Aqueous Media

Abstract

The montmorillonite K10-catalyzed aza Diels-Alder reaction of Danishefsky's diene with aldimines, generated in situ from aliphatic aldehydes and p-anisidine, proceeded smoothly in H 2 O or in aqueous CH 3 CN to afford 2-substituted 2,3-dihydro-4-pyridones in excellent yields.

Organic Reactions in Aqueous Media with a Focus on Carbon−Carbon Bond Formations: A Decade Update

“…The montmorillonite K10-catalyzed aza-Diels−Alder reaction of Danishefsky's diene with aldimines, generated in situ from aliphatic aldehydes and p -anisidine, proceeded smoothly in H 2 O or in aqueous CH 3 CN to afford 2-substituted 2,3-dihydro-4-pyridones in excellent yields . Also, complex [(PPh 3 )Ag(CB 11 H 6 Br 6 )] was shown to be an effective and selective catalyst (0.1 mol % loading) for a hetero-Diels−Alder reaction with Danishefsky's diene and showed a striking dependence on the presence of trace amounts of water .…”

More Sustainable Approaches for the Synthesis of N-Based Heterocycles

“…Finally, Akiyama et al reported the aza-Diels−Alder reaction of Danishefsky’s diene with aldimines catalyzed by montmorillonite K-10. A distinguishing feature of this three-component reaction is the fact that aliphatic aldehydes reacted smoothly in the presence of small amounts of montmorillonite K-10 in water, water/acetonitrile, or acetonitrile (Table ) …”

“…A distinguishing feature of this threecomponent reaction is the fact that aliphatic aldehydes reacted smoothly in the presence of small amounts of montmorillonite K-10 in water, water/acetonitrile, or acetonitrile (Table 68). 516 Six-membered heterocycles were synthesized following an intramolecular Diels-Alder protocol catalyzed by indium(III) trifluoromethanosulfonate in aqueous media by Taguchi et al This method takes advantage of the well-known catalytic activity of some rare earth metals (Sc(OTf) 3 , Yb(OTf) 3 , or In(III) salts), which act as Lewis acids. 517 The reaction afforded the cycloaddition adduct in 74% yield with a remarkable diastereoselectivity, providing only the endo stereoisomer (Scheme 123).…”

Montmorillonite K10 Catalyzed Nucleophilic Addition Reaction to Aldimines in Water

“…We have already reported that Montmorillonite K10 is an effective acid catalyst for the aza-Diels-Alder reaction of Danishefsky's diene with imines in aqueous media (Scheme 1). 9 We wish to report herein that the Mannich-type reaction 10 of silyl enolate with aldimine is effected by Montmorillonite K10 in water to afford b-amino carbonyl compounds in high yields. 11 Furthermore, hydrophosphonylation 12 of imine with dialkyl phosphite took place smoothly by means of Montmorillonite K10 to afford a-amino phosphonates in high yields.…”