Asymmetric Intramolecular Oxa‐Michael Reactions of Cyclohexadienones Catalyzed by a Primary Amine Salt

Abstract

Scheme 1. Brønsted acid-catalyzed enantioselective intramolecular oxa-Michael reaction.Scheme 2. General reaction design.

Applications of N′-monofunctionalised TsDPEN derivatives in asymmetric catalysis

“…The use of the ligands used in the above reaction on a more complex substrate has been reported; note that the reactions had to be carried out at 50 o C; at a lower temperature the fully cyclised products were not formed ( Figure 18). [38] Use of different catalyst enantiomers resulted in formation of diastereoisomeric products as would be expected from catalyst-control of the reactions. A squaramide-sulfonamide was applied to control a series of vinylogous aldol reactions.…”

Asymmetric [5+3] Formal Cycloadditions with Cyclic Enones through Cascade Dienamine–Dienamine Catalysis

“…[9] A commercially available chiral amine, (R,R)-1,2-diphenylethanediamine (1 d), predominantly produced the desired product 6 with much higher enantioselectivity. [14] An excellent ee value (91 %) with a moderate yield for 6 was finally obtained by employing 1 e as the catalyst. [15] The bis(electrophilic) partners are not limited to 3-vinyl-1,2-benzoisothiazole-1,1-dioxides.…”

Organocatalytic enantioselective desymmetrisation

“…198 The reported substrate scope demonstrated tolerance of alkyl, aryl and alkoxy substitution in the 4-position of the cyclohexadienone, resulting in the production of a range of enantioenriched 1,4-dioxane derivatives. 198 The reported substrate scope demonstrated tolerance of alkyl, aryl and alkoxy substitution in the 4-position of the cyclohexadienone, resulting in the production of a range of enantioenriched 1,4-dioxane derivatives.…”