Hughes, Gregory; Kreher, David; Wang, Changsheng; Batsanov, Andrei S.; Bryce, Martin R. published the artcile< Ethynyl π-extended 2,5-diphenyl-1,3,4-oxadiazoles and 2-phenyl 5-(2-thienyl)-1,3,4-oxadiazoles: synthesis, X-ray crystal structures and optical properties>, SDS of cas: 88105-22-0, the main research area is butylphenyl ethynylphenyl oxadiazole heteroaryl iodide Sonogashira cross coupling palladium; heteroarylethynylphenyl oxadiazole preparation optical property; ethynylthienyl oxadiazole heteroaryl iodide Sonogashira cross coupling palladium; oxadiazole phenyl ethynylthienyl preparation optical property crystal structure.
2-(4-Tert-Butylphenyl)-5-(4-ethynylphenyl)-1,3,4-oxadiazole (I, R = H) reacted with a series of heteroaryl iodides under standard Sonogashira cross-coupling conditions to yield products I [R = 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazyl (II), 5-bromo-2-pyrimidyl, 2-thienyl (III) and 3-thienyl (IV)] in 40-79% yields. Compound III was lithiated followed by electrophilic iodination using perfluorohexyl iodide to give the corresponding iodothienyl derivative, which by a two-step sequence gave the terminal ethynylthienyl derivative V (R’ = H) . Conversion of V into the terminal ethynylaldehyde derivative V (R’ = CHO) via acetal derivative proceeded in high yield. Starting from 2-iodo-5-methoxycarbonylthiophene, a five-step sequence afforded 2-(4-tert-butylphenyl)-5-(4-ethynylthienyl)-1,3,4-oxadiazole (VI, R = H) (13% overall yield). Sonogashira cross-coupling reactions of VI with heteroaryl iodides gave 2-phenyl-5-(2-thienyl)-1,3,4-oxadiazoles VI (R = 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazyl (VII), 5-bromo-2-pyrimidyl, 2-thienyl and 3-thienyl). Two-fold reaction of V with 2,5-diiodothiophene gave the bis(ethynylthienyl)thiophene derivative (30% yield). Solution UV-Vis absorption and photoluminescence spectra establish that replacement of the Ph ring in the 2,5-diphenyl-1,3,4-oxadiazole series I by a thienyl ring as in VI leads to a red shift in the lowest energy band in both the absorption spectra and emission spectra. The X-ray crystal structures of compounds II, IV, V and VII·CHCl3 reveal that the mol. structures are approx. planar although there are substantial differences in the conformations.
Organic & Biomolecular Chemistry published new progress about Aryl iodides Role: RCT (Reactant), RACT (Reactant or Reagent). 88105-22-0 belongs to class iodides-buliding-blocks, and the molecular formula is C6H5IO2S, SDS of cas: 88105-22-0.
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com