Reactions of halothiophenes with metal amides. Convenient preparation of .beta.-bromothiophenes

Abstract

A new, convenient, and efficient synthesis of the very useful d-bromothiophenes by the metal amide catalyzed rearrangement of the readily available a isomers is reported.

Formal Lossen Rearrangement/Alkenylation or Annulation Cascade of Heterole Carboxamides with Alkynes Catalyzed by CpRhIII Complexes with Pendant Amides

“…Importantly,t he above alkenylation and annulation products have not been prepared from the corresponding N-carbonyl aminoheteroles (Scheme 3b,l eft) due to their low stabilitya nd limited availability. [19] Furthermore, alkenylated and [5,5]-fused thiophene derivatives are found in biologically active compounds (e.g.,a gricultural fungicides [20] and inhibitors of the Hepatitis Cv irus, [21] Figure1,t op), the syntheses of which are problematic. For ex-Scheme3.Rhodium(III)-catalyzed annulation and alkenylation reactions.L G= leavingg roup.…”

Indexing Integrated Manual Sets at Northern Telecom

“…Mass spectra were recorded on a JEOL JMS‐GCmate II mass spectrometer or a BRUKER Autoflex MALDI TOF mass spectrometer. Compound 7 ,11 10 ,12 11 ,13 17 ,14 and 1‐iodo‐4‐methoxymethoxybenzene15 were prepared according to the method reported previously. Tosylated derivative of poly(ethylene glycol) monomethyl ether was prepared by the method reported for TsOHxg 5…”

The 2×3 Toolbox of Organometallic Methods for Regiochemically Exhaustive Functionalization

“…If a suitably located bromine or iodine atom is present, heavy‐halogen migrations can be observed. Such processes have been investigated more or less extensively by the groups of Gronowitz (thiophenes),71, 72 van der Plas (isothiazoles,73 pyrazoles,74 thiophenes75), Reinecke (thiophenes),76, 77 Shibuya (thiophenes),78 Taylor (thiophenes),79 Fröhlich (furans,80, 81 thiophenes82, 83), and Quéguiner (pyridines,84, 85 quinolines86).…”