81580-88-3Relevant academic research and scientific papers
Pyridine-catalyzed desulfonative borylation of benzyl sulfones
Maekawa, Yuuki,Ariki, Zachary T.,Nambo, Masakazu,Crudden, Cathleen M.
, p. 7300 - 7303 (2019)
Herein, we report the transition-metal free, pyridine-catalyzed desulfonative borylation of benzyl sulfones with bis(pinacolato)diboron (B2pin2). A variety of benzhydryl- and benzyl boronic esters could be synthesized from readily prepared sulfone derivatives. The borylation of cyclic sulfones accompanied by ring opening also proceeded to afford the corresponding sulfonate, which could be converted into functionalized sulfones and sulfonamides.
Addition Reactions of Benzothiophen. Part 3. Addition and Ring-opening Reactions with Phenolic Ethers
Clark, Peter David,Ewing, David F.,Kerrigan, Frank,Scrowston, Richard M.
, p. 615 - 622 (2007/10/02)
In the presence of aluminium chloride, anisole, phenetole, diphenyl ether, and (methylthio)benzene are added rapidly across the 2,3-bond in benzothiophen to give, inter alia, a mixture of 2- and 3-(p-substituted aryl)-2,3-dihydrobenzothiophens (3) and (4).Contrary to expectation, the 2-isomer predominates in all cases, and the addition is irreversible.Reaction with anisole also leads to a novel ring-opened product, viz. (E)-4-methoxy-2'-methylthiostilbene (9a), which was synthesised unambigiuously.It is believed that benzothiophen is S-methylated by PhOMe-AlCl3 in a 'push-pull' reaction, and that the resulting positive charge is delocalised into the ring, thus allowing the 2-position to participate in electrophilic attack on a second molecule of anisole.The resulting quadrivalent sulphur intermediate achieves stabilisation by means of a rapid ring-opening reaction.Other aromatic methyl ethers give analogous products, but phenetole diphenyl ether, and (methylthio)benzene do not promote ring-opening.The ring-opening reaction is aided by the addition of MeBr- or EtBr-AlCl3; even phenetole will then undergo ring-opening.Under these conditions the S-alkyl group in the ring-opened product comes from the starting ether, and not from the added MeBr or EtBr.
