862175-45-9Relevant academic research and scientific papers
Click chemistry as a powerful tool for the construction of functional poly(p-phenyleneethynylene)s: Comparison of pre- and postfunctionalization schemes
Englert, Brian C.,Bakbak, Selma,Bunz, Uwe H. F.
, p. 5868 - 5877 (2005)
1,3-Dipolar cycloadditions have been used to prepare a series of functionalized poly(p-phenyleneethynylene)s (PPEs). This was accomplished by employing a PPE with pendent triisopropylsilylacetylene groups. The triisopropylsilyl groups can be removed in si
Postsynthetic Modification of Metal-Organic Frameworks through Nitrile Oxide-Alkyne Cycloaddition
Von Zons, Tobias,Brokmann, Luisa,Lippke, Jann,Preu?e, Thomas,Hülsmann, Miriam,Schaate, Andreas,Behrens, Peter,Godt, Adelheid
supporting information, p. 3348 - 3359 (2018/03/25)
Postsynthetic modification of metal-organic frameworks is an important method to tailor their properties. We report on the nitrile oxide-alkyne cycloaddition (NOAC) as a modification tool, a reaction requiring neither strained alkynes nor a catalyst. This is demonstrated with the reaction of nitrile oxides with PEPEP-PIZOF-15 and -19 at room temperature. PIZOF-15 and -19 are porous Zr-based MOFs (BET surface areas 1740 and 960 m2 g-1, respectively) consisting of two mutually interpenetrating UiO-type frameworks with linkers of the type -O2C[PE-P(R1,R2)-EP]CO2- (P, phenylene; E, ethynylene; R1 and R2, side chains at the central benzene ring with R1 = R2 = OCH2C≡CH or R1 = OCH2C≡CH and R2 = O(CH2CH2O)3Me). Their syntheses, using benzoic acid as a modulator, and their characterization are reported herein. The propargyloxy (OCH2C≡CH) side chains contain the ethyne moieties needed for NOAC. Formation of nitrile oxides through oxidation of oximes in aqueous ethanolic solution in the presence of PEPEP-PIZOF-15 and -19 resulted in the reaction of 96-100% of the ethyne moieties to give isoxazoles. Thereby the framework was preserved. The type of nitrile oxide RCNO was greatly varied with R being isopentyl, tolyl, 2-pyridyl, and pentafluorophenyl. A detailed NMR spectroscopic investigation showed the formation of the 3,5-disubstituted isoxazole to be clearly favored (≥96%) over that of the constitutional isomeric 3,4-disubstituted isoxazole, except for one example.
