74111-21-0

 https://www.lookchem.com/CASDataBase_74111-21-0.htm

(Chemical Equation Presented) Linear (n = 2-18) and cyclic oligomers (n = 3-8) of a cyclohexylether-δ-amino acid (COA) were prepared in high yield and stereopurity. CD spectra of the linear oligomers were indicative of secondary structure formation. X-ray crystal structures of cyclic COA oligomers revealed hydrophobic packing and internal 5- and 10-membered-ring hydrogen bonds. Ether and amide oxygens reside preferably in an ap orientation. This conformational locking is apparently broken by a C-2 substituent in an asymmetric cyclotrimer, for which a zeolithe-like tubular structure was found.

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100-48-1 In situ immobilized palladium nanoparticles on surface of poly-methyldopa coated-magnetic nanoparticles (Fe3O4@PMDA/Pd): A magnetically recyclable nanocatalyst for cyanation of aryl halides with K4[Fe(CN)6]

Poly-methyldopa (PMDP)-coated Fe 3 O 4 nanoparticles (Fe 3 O 4 @PMDP) have been synthesized through a simple and green procedure. In the present study, for the first time, Pd nanoparticles were successfully deposited using Fe 3 O 4 @PMDP as a core-shell magnetic coordinator and stabilizer agent. In this protocol, Pd ions were adsorbed on surfaces of Fe 3 O 4 @PMDP through immersion of the PMDP-coated Fe 3 O 4 nanoparticles into a palladium plating bath. Next, they were reduced in situ to palladium nanoparticles using PMDP's N-containing groups and reducing ability. The structure, morphology and physicochemical properties of the synthesized nanoparticles were characterized by different analytical techniques such as energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscope (FESEM), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, high resolution transmission electron microscopy (HR-TEM), inductively coupled plasma (ICP), thermo gravimetric
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767-58-8 The Photochemistry of Conformationally Rigid Benzylic Esters: 2,2-Dimethyl-1-indanyl Acetates and Pivalates

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7439-96-5 Preparation, characterization and thermal reactivity of n,n-dimethylformamide complexes of some transition metal chlorides

The coordination adducts of MnCl 2 , FeCl 3 , CoCl 2 , NiCl 2 and CuCl 2 with DMF were isolated and characterized by elemental analysis, magnetic moments, UV-VIS spectroscopy, IR spectroscopy and thermal analysis techniques. The shift of the CO stretching vibration to low frequency indicated that DMF is bonded through oxygen to the metals. On the basis of spectral and elemental analysis data, the complexes have dimeric and trimeric structures achieved by the chlorine bridges. The complexes do not have melting points and undergo decomposition after dehydration. The decomposition of DMF in the complexes occurs in several stages and the last stages of decomposition always corresponds to decomposition or sublimation of the respective metal chlorides to produce the respective metal. https://www.lookchem.com/CASDataBase_7439-96-5.htm
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