68108-90-7Relevant articles and documents
A convenient access to thermodynamically nonstabilised spiroketal isomers: The first synthesis of (Z)-7-methyl-1,6-dioxaspiro[4.5]decane
Doubsky, Jan,?aman, David,Zedník, Ji?í,Va?í?ková, Soňa,Koutek, Bohumír
, p. 7923 - 7926 (2005)
Functionalised hydroxy α-alkynones were transformed to the corresponding spiroketals by a one-pot cascade consisting of palladium-catalysed hydrogenation of the triple bond, hydroxyl group deprotection and spirocyclisation under mild nonacidic conditions. The reaction does not rely upon thermodynamic control to set the configuration of the ketal stereocentre so that both the anomerically stabilised and nonstabilised isomers are similarly accessible.
Lipase mediated resolution of 1,3-butanediol derivatives: Chiral building blocks for pheromone enantiosynthesis. Part 3
Izquierdo, Isidoro,Plaza, Maria T.,Rodriguez, Miguel,Tamayo, Juan A.,Martos, Alicia
, p. 293 - 300 (2007/10/03)
(R,S)-1,3-Butanediol 5 was kinetically resolved by enzymatic acetylation with vinyl acetate under the presence of Chirazyme L-2, c-f, yielding (S)-1-O-acetyl-1,3-hydroxybutane 6 and (R)-1,3-di-O-acetyl-1,3-butanediol 7 with enantiomeric excesses of 91% (E = 67.3). Compounds 6 and 7 were easily transformed into the corresponding (S)-3-O-(2-methoxyethoxymethyl)-3-hydroxybutanal 10 and (R)-3-benzyloxybutanal 19, through a protection-deprotection and functional group interchange methodology. Subsequent reaction of 10 and 19 with 3-(methoxycarbonylpropionylmethylene)triphenylphosphorane afforded methyl (E,S)-8-O-(2-methoxyethoxymethyl)-4-oxo-5-nonenoate 12 and (E,R)-8-benzyloxy-4-oxo-5-nonenoate 20. The alkenes 19 and 20 were then catalytically hydrogenated to the corresponding saturated esters 13 and 21. Treatment of 13 and 21 with 1,2-ethanedithiol/F3B·OEt2 afforded dithioketals 14 and 22, which were respectively reduced to (S)-1,8-dihydroxy-4-nonanone ethylidenedithioketal 15 and (R)-8-O-benzyl-1,8-dihydroxy-4-nonanone ethylidenedithioketal 23. Finally, deprotection of 15 by catalytic hydrogenation under acidic conditions gave the expected (5S,7S)-(-)-7-methyl-1,6-dioxaspiro[4.5]decane 1. The (5R,7R)-(+)-1 enantiomer was analogously prepared from 23. Both compounds were formed by this procedure with an e.e. of 91%.
A Modified Synthesis of (+/-)-(E)-7-Methyl-1,6-dioxaspirodecane
Wu, Yikang,Ohlsson, Elisabeth
, p. 422 - 424 (2007/10/02)
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