Zinc-catalyzed asymmetric [3 + 2] annulations for the construction of chiral spiro[1-indanone-γ-butyrolactones] via a C–N bond cleavage process

Abstract

An intriguing tandem Michael/lactonization reaction of α-hydroxy-1-indanones and methyleneindolinones has been established in this work. The employ of chiral dinuclear zinc catalysts is essential in achieving highly efficient chirality transfer...

Reversal of enantioselectivity by tuning the ring size of ProPhenol

“…32–42 The excellent performance of this ligand also attracted our attention. 43–49 In 2014, we reported the ProPhenol analogue ( S , S )- L 4 as a new addition to the chiral aza-crown family by replacing the prolinol moieties with chiral azetidines (Fig. 1C).…”

Zinc-Catalyzed Enantioselective [3 + 3] Annulation for Synthesis of Chiral Spiro[indoline-3,4′-thiopyrano[2,3-b]indole] Derivatives

“…However, there are no reports on metal-catalyzed asymmetric cascade annulations of the indoline-2-thiones. Herein, we describe the application of Bronsted base and Lewis acid cooperative activation [ 44 , 45 , 46 , 47 ] to the synthesis of spiro[indoline-3,4′-thiopyrano[2,3- b ]indole] derivatives via the Friedel–Crafts alkylation/cyclization tandem reactions of indoline-2-thiones and isatylidene malononitriles [ 48 , 49 , 50 , 51 ] ( Scheme 1 b).…”

Acyl transfer-enabled catalytic asymmetric Michael addition of α-hydroxy-1-indanones to nitroolefins

“…Our group has a long-standing interest in developing facile protocols for synthesizing biologically important molecules. Recently, we have discovered that α-hydroxy-1-indanones could serve as a valid synthon in cyclization reactions with activated Michael acceptors via chiral dinuclear zinc catalysis [23,24] . Along this line, we envisioned that dinuclear zinc-catalyzed asymmetric acyl transfer reaction between α-hydroxy-1indanones 1 and nitroenones 2 was feasible via less-explored electrophile activation mechanism, generating thereby the protected cyclic tertiary α-hydroxyketones 3 in an enantioselective, step-and atom-economic manner.…”