207804-93-1Relevant academic research and scientific papers
Sulfones as Synthetic Linchpins: Transition-Metal-Free sp3–sp2 and sp2–sp2 Cross-Couplings Between Geminal Bis(sulfones) and Organolithium Compounds
Trost, Barry M.,Kalnmals, Christopher A.
supporting information, p. 9066 - 9074 (2018/06/29)
A valuable umpolung strategy that highlights the ambiphilic nature of the bis(phenylsulfonyl)methyl synthon and demonstrates its utility as a synthetic linchpin is reported. Although the bis(phenylsulfonyl)methyl group is typically introduced as an sp3-carbon nucleophile, it is demonstrated that it can also function as an effective sp2-carbon electrophile in the presence of organolithium nucleophiles. Alkyl- and aryllithiums couple with the central carbon of the bis(phenylsulfonyl)methyl unit to ultimately generate trisubstituted alkenes, comprising formal sp3–sp2 and sp2–sp2 cross-couplings between organolithium reagents and bis(sulfones). This process occurs almost instantaneously at ?78 °C in the absence of any transition metals. By developing this curious transformation, it has been demonstrated that bis(phenylsulfonyl)methane is a valuable synthetic linchpin, which can undergo two C?C bond-forming processes as an sp3-nucleophile, followed by a third C?C bond-forming reaction as an effective sp2-electrophile. This discovery significantly enhances the utility of this ubiquitous, but underutilized, linker group.
