Synthesis and ring-opening reactions of cationic ruthenium biaryl thionolactone complexes
摘要:
The preparations of novel thionolactone-bridged configuratively labile biaryls and their [Cp(R3P)2Ru]+-complexes are described. The dynamics of helimerization of these complexes and their reactivity towards nucleophiles have been investigated. Hydride transfer reagents lead to a cleavage of the thionolactone bridge to give the corresponding thiolate complexes, apparently via intermediate exothiolactolate ruthenium complexes. A similar lactolate analog is formed upon addition of a mild S-nucleophile.
Synthesis and ring-opening reactions of cationic ruthenium biaryl thionolactone complexes
摘要:
The preparations of novel thionolactone-bridged configuratively labile biaryls and their [Cp(R3P)2Ru]+-complexes are described. The dynamics of helimerization of these complexes and their reactivity towards nucleophiles have been investigated. Hydride transfer reagents lead to a cleavage of the thionolactone bridge to give the corresponding thiolate complexes, apparently via intermediate exothiolactolate ruthenium complexes. A similar lactolate analog is formed upon addition of a mild S-nucleophile.
Atropo-Enantioselective Ring Cleavage of Lewis Acid Modified Biaryl Thionolactones<sup>,</sup>
作者:Gerhard Bringmann、Andreas Wuzik、Jörg Kümmel、Wolfdieter A. Schenk
DOI:10.1021/om001040e
日期:2001.4.1
Attachment of an achiral, ruthenium-based Lewis acid fragment to configurationally unstable biaryl thionolactones 1a−1c, atropo-enantioselective reductive lactone cleavage of the resulting complexes with chiral hydride reagents, and subsequent decomplexation leads to axially chiral thioethers 3a−3c with enantiomeric ratios of up to 92:8.