Applications of Serebryakov–Jørgensen Dienamines (1-Aminobuta-1,3-Dienes) in Domino or Cascade Reactions

Abstract

Discussed here is the in situ generation of 1-aminobuta-1,3-dienes (Serebryakov–Jørgensen dienamine intermediates) along with a few other modes of activation of unsaturated carbonyl compounds and their potential in a sequence of reactions in a single pot. Designing and performing these cascade reactions was achievable due to the existence of different modes of activation under amine catalysis. Asymmetric synthesis of dihydrocoumarins, a variety of spirocyclic oxindoles, such as cyclopropane spirooxindoles, spiro-oxindolic cyclopentanes, spiro-oxindolic cyclohexanes containing six stereocenters and drug-like spiro[chroman-3,3′-indolin]-2′-ones, were easily achieved from these domino reactions. Further, Serebryakov–Jørgensen dienamines found foothold in highly regio- and stereo-selective asymmetric remote aziridination, atroposelective aldol condensation for the synthesis of axially chiral biaryls, an γ-alkylation–annulation sequence for access to few carbocyclic structures, a Morita–Baylis–Hillman/Michael/acetalization sequence for the asymmetric synthesis of fully substituted tetrahydropyran, and the intramolecular aldol condensation and Friedel–Crafts sequence for diheteroarylalkanal synthesis. Moreover, these dienamines were utilized in regio- and enantio-selective domino aldol-oxa-Michael reactions with salicylaldehydes for the construction of novel chroman derivatives possessing quaternary stereocenters.