The base-promoted reaction of 3-sulfolene with bis-vinyl ketones was shown in earlier work to proceed through a γ-1,2 addition/anionic oxy-Cope cascade; a subsequent treatment with base induced a second γ-1,2 addition to provide a [3.3.0] bicyclic framework that our group then exploited in the design of rigidified enzyme inhibitors for influenza neuraminidase. Out of a desire to expand the rang...

Chiral framework: Chiral amines with pyrrolidine frameworks catalyze the enantioselective conjugate addition of a wide range of aldehydes to various vinyl sulfones and vinyl phosphonates in high yields and with enantioselectivities up to >99 % ee (see scheme). The high versatility of the Michael adducts is exemplified by various functionalizations with conservation of the optical purity.Chiral ...

The reaction of a series of allyl-substituted bis(phenylsulfony1)methanes or dimethyl malonates with 2,3-bis(phenylsulfonyl)l13-butadiene in the presence of base afforded alkenyl-substituted allenes in good yield. The reaction proceeds by initial attack of the soft carbanion onto the terminal position of the diene and subsequent PhS02elimination to give the phenylsulfonyl substituted allene. Th...

The bifunctional thiourea-tertiary amine derivatives of simple chiral diamines serve as highly enantioselective catalysts for the Michael addition of alpha-substituted cyanoacetates to vinyl sulfones, giving an efficient protocol for the construction of an all-carbon substituted quaternary stereocentre.

Titanocene(II)-promoted cross-coupling between (Z)-alkenyl methyl sulfones and terminal allenes produced 1,4-dienes regioselectively via the formation of 2-alkylidenetitanacyclopentanes. Preferential formation of E,Z-dienes was observed in the reaction using aryl-, amino-, and phosphinylallenes.