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A direct method for the synthesis of ?,?-disubstituted-?,?-unsaturated aldehydes via Heck reaction of aryl halides with crotonaldehyde and related substrates has been developed. The reaction provides rapid access to products usually prepared via multistep sequences. The power of the method in combination with an organocatalytic transfer hydrogenation is illustrated with a short asymmetric synthesis of ( S)-Florhydral ?. [ABSTRACT FROM AUTHOR]

A CH-activation and deprotonation of 8-methyl-8-azabicyclo3.2.1oct-2-ene (tropidine, 1) occurs upon reaction with TiCl4and ZrCl4to afford the allyl complexes monotropidinyl titanium trichloride (4) and ditropidinyl zirconium dichloride (7), respectively. Tropidine (1) itself acts as the HCl scavenger, and the reactions are accompanied by the formation of 1 equiv of the hydrochloride 1·HCl. The crystal structure of 4is reported. [ABSTRACT FROM AUTHOR]