An efficient catalytic and highly enantioselective protonation of silyl ketene imines is described. The reaction is catalyzed by the chiral phosphoric acids TRIP or STRIP in the presence of a stoichiometric amount of methanol as the proton source and silyl acceptor. A variety of substituted racemic silyl ketene imines have been transformed into highly enantioenriched nitriles.

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A new one-pot room-temperature palladium-catalyzed synthesis of 7-aryltetralones was discovered. This tandem process includes a palladium-catalyzed gamma-selective arylation of the enone 4 followed by a dehydrogenation-aromatization of the initial cross-coupling product. [reaction: see text]

[reaction: see text] The enantioselective total synthesis of (+)-neosymbioimine was accomplished in 18 steps from (-)-(S)-citronellol utilizing an organocatalytic alpha-oxidation of aldehyde 6. The carbon core was constructed by a tandem Horner-Wadsworth-Emmons (HWE) reaction and an intramolecular Diels-Alder cyclization. All double bonds of 12 were made in a stereoselective manner by Wittig-type reactions. Selective formation of the monosulfate monoester was accomplished by one-pot excessive sulfation followed by kinetic hydrolysis of bissulfate 18 in 79% yield.