The regioselective intramolecular 1,3-dipolar cycloaddition of the phenylsulfonylallene-nitrone derivatives has been developed. This reaction showed that the distal double bond of the allene exclusively reacted with the nitrone group to produce the bicyclic isoxazolidine derivatives regardless of the substitution pattern on the allenyl moiety.
Chemistry of allenic/propargylic anions generated by base treatment of sulfonylallenes: synthesis of 1-alkynyl-1-sulfonylcycloalkanes and cycloalkanols
The intramolecular trapping of allenyl/propargyl anions, generated from sulfonylallenes with the proper base, by a haloalkyl group or an aldehyde functionality was investigated. The treatment of 1-(omega-iodoalkyl)-1-(phenylsulfonyl)allenes with TBAF or NaH in DMF efficiently produced the 1-alkynyl-1-(phenylsulfonyl)-substituted three- to seven-membered carbocycles. The allenyl/propargyl anions could also be intramolecularly trapped using a terminal aldehyde to stereoselectively afford the 2-alkynyl-2-(phenylsulfonyl)-substituted five- and six-membered cycloalkanols. The latter reaction could be performed using a catalytic amount of TBAF or DBU. (C) 2010 Elsevier Ltd. All rights reserved.
Ring-Closing Reaction of Allenic/Propargylic Anions Generated by Base Treatment of Sulfonylallenes
作者:Shinji Kitagaki、Satoshi Teramoto、Chisato Mukai
DOI:10.1021/ol0709329
日期:2007.6.1
The intramolecular trapping of allenyl/propargyl anions generated by base treatment of sulfonylallenes was investigated. Treatment of 1-(omega-iodoalkyl)-1-(phenylsulfonyl)allenes with TBAF or NaH in DMF efficiently produced three- to seven-membered 1-ethynyl-1-(phenylsulfonyl) substituted carbocycles. The allenyl/propargyl anions could also be intramolecularly trapped using a terminal aldehyde or