A new method for the enantioselective synthesis of highly functionalized dihydrofurans has been developed. This process, related to the interrupted Feist–Bénary reaction, involves the reaction of 2-ene 1,4-diketones with dimedone in the presence of bis(cinchona alkaloid)pyrimidine catalysts to afford dihydrofuran products in excellent yields and high diastereo- and enantioselectivities.

We have found that the thiophenesulfonyl group is compatible with the catalytic, asymmetric synthesis of β-lactams from acid chlorides and sulfonyl imines in the presence of a silylated cinchona alkaloid and tris(hexamethyl disilazide) lanthanide complex co-catalysts. The thiophenesulfonyl group can be subsequently removed in moderate yields without causing decomposition of the β-lactam or lowering its stereochemical purity.

Total syntheses of (−)-variabilin and (−)-glycinol have been accomplished, using the catalytic, asymmetric “interrupted” Feist–Bénary reaction (IFB) as the key transformation to introduce both stereogenic centers. A monoquinidine pyrimidinyl ether catalyst affords the IFB products in over 90% ee in both cases. Other key steps include an intramolecular Buchwald–Hartwig coupling and a nickel-catalyzed aryl tosylate reduction.

A new variant of the Interrupted Feist–Bénary (IFB) reaction uses α-tosyloxyacetophenones as electrophiles and proceeds in good yields and excellent enantioselectivities.

Newly synthesized cinchona alkaloid-derived pyrimidines function as effective asymmetric catalysts for the Michael reaction between cyclic diketones and β,γ-unsaturated α-ketoesters. The reactions of electrophiles with either aryl or alkyl γ-substituents give 64−99% yields and 94−99% ee.