Trost, Barry M. published the artcileSulfones as Synthetic Linchpins: Transition-Metal-Free sp3-sp2 and sp2-sp2 Cross-Couplings Between Geminal Bis(sulfones) and Organolithium Compounds, Application of 2-Bromo-4-methoxybenzoic acid, the main research area is substituted dihydronaphthalene preparation; geminal bis sulfone organolithium compound coupling; cross-coupling; sulfones; synthesis design; transition-metal-free; umpolung.
A valuable umpolung strategy that highlights the ambiphilic nature of the bis(phenylsulfonyl)methyl synthons and demonstrates its utility as a synthetic linchpin is reported. Alkyl- and aryllithiums couple with the central carbon of the bis(phenylsulfonyl)methyl unit to ultimately generate trisubstituted alkenes I [R = H, 6-MeO, 7-F, etc.; R1 = n-Bu, Ph, (CH2)2C6H5, etc.], 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.
Chemistry – A European Journal published new progress about Acidity function, Hammett. 74317-85-4 belongs to class bromides-buliding-blocks, name is 2-Bromo-4-methoxybenzoic acid, and the molecular formula is C8H7BrO3, Application of 2-Bromo-4-methoxybenzoic acid.
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary