Facile, regio and stereoselective Diels-Alder reactions of allenic trichloromethyl sulfones and sulfoxides
摘要:
The dienophilic reactivity of allenes is drastically increased by the powerful electron withdrawing trichloromethylsulfonyl or sulfinyl substituents. The [4+2]-cycloadditions proceed smoothly with high regio- and stereoselectivity under mild conditions. Using an optically active allenyl sulfone, transfer of chirality has been observed.
reactivity of allenic trichloromethyl sulfoxides under ultrasound irradiation has been investigated. A considerable rate enhancement has been observed for cycloaddition of the unsubstituted and γ-monosubstituted allenyl trichloromethyl sulfoxides to cyclopentadiene. With the corresponding γ,γ-disubstituted allenic sulfoxides, a competing 1,2- to 1,3-diene isomerization is observed.
Facile, regio and stereoselective Diels-Alder reactions of allenic trichloromethyl sulfones and sulfoxides
作者:Samuel Braverman、Zvi Lior
DOI:10.1016/s0040-4039(00)73478-2
日期:1994.9
The dienophilic reactivity of allenes is drastically increased by the powerful electron withdrawing trichloromethylsulfonyl or sulfinyl substituents. The [4+2]-cycloadditions proceed smoothly with high regio- and stereoselectivity under mild conditions. Using an optically active allenyl sulfone, transfer of chirality has been observed.