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At low temperature and in the presence of an acid catalyst, SO2 adds to 1,3-dienes equilibrating with the corresponding 3,6-dihydro-1,2-oxathiin-2-oxides (sultines). These compounds are unstable above -60 degrees C and equilibrate with the more stable 2,5- ...
At low temperature, 1-alkoxy-1,3-dienes add to sulfur dioxide activated by a Lewis or protic acid generating zwitterionic intermediates that can be quenched by enoxysilanes. The resulting beta,gamma-unsaturated silyl sulfinates can be desilylated by 1:1 Pd ...
2004
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In the presence of sulfur dioxide and an acid promoter, (-)-(1E,3Z)-2-methyl-1-((1S)-1-phenyleth- oxy)penta-1,3-dien-3-yl isobutyrate reacts with (Z)-3-(trimethylsilyloxy)-pent-2-ene giving a silyl sulfinate intermediate that undergoes, in the presence of ...
2005
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The reaction of (E,E)-1-benzyloxy-2-methylpenta-1,3-diene with trimethylsilyl enol ethers derived from acetone or acetophenone with sulfur dioxide precomplexed with ytterbium triflate or (CF3SO2)(2)NH generates sulfinate intermediates that can be quenched ...
Alcohols, phenols and carboxylic acids are silylated with very good yields in the presence of silyl methallylsulfinates under non- basic conditions and with the formation of volatile co-products. ...
Sulphur dioxide reacts with 1-oxydienes generating zwitterions which are quenched by enoxysilanes to form substituted silyl alkenylsulfinates. These intermediates are desilylated with Bu4NF and the resulting sulfinates react with MeI giving the correspondi ...