65689-53-4Relevant articles and documents
2,2'-Bi[benzo[b]thiophene]: An unexpected isolation of the benzo[b]thiophene dimer
Cheung, Eugene Y.,Pennington, Lewis D.,Bartberger, Michael D.,Staples, Richard J.
, p. 547 - 549 (2014)
The crystal structure of 2,2'-bi[benzo[b]thiophene], C16H 10S2, at 173K has triclinic (P1) symmetry. It is of interest with respect to its apparent mode of synthesis, as it is a by-product of a Stille cross-coupling reaction in which it was not explictly detected by spectroscopic methods. It was upon crystal structure analysis of a specimen isolated from the mother liquor that this reaction was determined to give rise to the title compound, which is a dimer arising from the starting material. Two independent half-molecules of this dimer comprise the asymmetric unit, and the full molecules are generated via inversion centers. Both molecules in the unit cell exhibit ring disorder, and they are essentially identical because of their rigidity and planarity.
Oxidative Homocoupling of Diheteroaryl- or Diarylmanganese Reagents Generated via Directed Manganation Using TMP2Mn
Haas, Diana,Hammann, Jeffrey M.,Moyeux, Alban,Cahiez, Gérard,Knochel, Paul
, p. 1515 - 1519 (2015)
We report an oxidative homocoupling of diheteroaryl or diarylmanganese reagents prepared by directed manganation using TMP2Mn·2MgCl2·4LiCl. The resulting diorganomanganese reagents can efficiently undergo an oxidative dimerization leading to the homocoupling products in good yields. Remarkably, a number of functional groups, as well as sensitive heterocycles are tolerated using this metalation-dimerization procedure.
Stereoselective synthesis of monoamine reuptake inhibitor NS9544 acetate
Malmgren, Hakan,Cotton, Hanna,Frostrup, Brian,Jones, David Spencer,Loke, Marie-Louise,Peters, Dan,Schultz, Sara,Soelver, Ellen,Thomsen, Tove,Wennerberg, Johan
, p. 408 - 412 (2011)
(-)-3-(2-Benzothienyl)-8-H-8-azabicyclo[3,2,1]oct-2-ene acetate, NS9544 acetate, is a candidate drug intended to treat pain and other CNS disorders. In the synthetic route tropinone was enantioselective deprotonated with a chiral lithium amide derived from [R-(R*,R*)]-bis(α-methylbenzyl) amine hydrochloride. The formed enolate was trapped as triflate and coupled with benzo[b]thiophene-2-boronic acid under Suzuki conditions. To further enhance the enantiomeric purity crystallisation with l-(+)-tartaric acid was performed. Finally N-demethylation with trichloroethylchloroformate followed by treatment with acetic acid afforded NS9544 as the acetate salt with high enantiomeric purity.
Iron-catalysed regioselective thienyl C–H/C–H coupling
Doba, Takahiro,Ilies, Laurean,Nakamura, Eiichi,Sato, Wataru,Shang, Rui
, p. 631 - 638 (2021/07/25)
Regioselective thienyl–thienyl coupling is arguably one of the most important transformations for organic electronic materials. A prototype of ideal organic synthesis to couple two thienyl groups by cutting two C–H bonds requires formal removal of two hydrogen atoms with an oxidant, which often limits the synthetic efficiency and versatility for oxidation-sensitive substrates (for example, donor and hole-transporting materials). Here, we found that diethyl oxalate, used together with AlMe3, acts as a two-electron acceptor in an iron-catalysed C–H activation. We describe the regioselective thienyl C–H/C–H coupling with an iron(III) catalyst, a trisphosphine ligand, AlMe3 and diethyl oxalate under mild conditions. The efficient catalytic system accelerated by ligand optimization polymerizes thiophene-containing monomers into homo- and copolymers bearing a variety of electron-donative π motifs. The findings suggest the versatility of iron catalysis for the synthesis of functional polymers, for which the potential of this ubiquitous metal has so far not been fully appreciated. [Figure not available: see fulltext.].
Nickel-catalyzed and Li-mediated regiospecific C-H arylation of benzothiophenes
Canivet, Jér?me,Grousset, Léonie,Hisler, Ga?lle,Mohr, Yorck,Quadrelli, Elsje Alessandra,Roux, Yoann,Wisser, Florian M.
, p. 3155 - 3161 (2020/06/19)
A nickel-based catalytic system for the regiospecific C2-H arylation of benzothiophene has been established. NiCl2(bpy) is used as a catalyst in combination with LiHMDS as a base in dioxane. The catalytic system is applicable to a variety of functionalized benzothiophenes, as well as other heteroarenes including thiophene, benzodithiophene, benzofuran and selenophene in combination with iodo aryl electrophiles. The role of LiHMDS as a uniquely potent base and a postulated mechanism are discussed. The applicability of this system is finally demonstrated for the synthesis of an intermediate of an active pharmaceutical ingredient.
