13752-97-1Relevant articles and documents
Thermochromism and solvatochromism of non-ionic polar polysilanes
Oka, Kunio,Fujiue, Naofumi,Nakanishi, Saburo,Takata, Toshikazu,West, Robert,Dohmaru, Takaaki
, p. 45 - 51 (2000)
Polar polysilanes bearing ethereal side groups [{CH3-Si-(CH2)m-O-(CH2CH 2O)n-CH3}x, m = 3-5 and n = 0-3}] were prepared and were found to be soluble in a wide range of polar solvents. UV spectroscopic behavior is highly dependent on the nature of the solvents used but no simple relationship between λmax and specific solvent parameter is found. Small molar absorbance (ε 3)2CHOH (HFIP) in non-polar solvent (benzene, CH2Cl2) or even in (CH3)2CHOH solution, where higher HFIP concentration brings about longer wavelength absorption. This type of solvatochromism is originated by strong hydrogen bond formation between the ethereal side groups and HFIP. Because non-dissociative nature of HFIP-concerned hydrogen bonding, increased bulkiness of the side moieties brings about disentanglement. Polysilanes 1-5, though having long side chains, show thermochromism of continuous spectral shift on cooling. The same λmax value in thermochromism and solvatochromism indicates that nearly the same degree of disentanglement is caused by HFIP and thermally.
Novel perfluoroalkylated oligo(oxyethylene) methyl ethers with high hemocompatibility and excellent co-emulsifying properties for potential biomedical uses
Kaplánek, Robert,Paleta, Old?ich,Ferjentsiková, Ivana,Kodí?ek, Milan
experimental part, p. 308 - 316 (2009/12/03)
Two series of novel perfluoroalkylated amphiphilic compounds were synthesized from monomethyl ethers of mono-, di- and tri-(oxyethylene) glycols. The first series CH3(OCH2CH2)nOCH2CH(OH)CH2-CF2(CF2CF2)nCF3 (n = 1-3) bearing the hydroxy group at the spacer between hydrophilic and hydrophobic parts was prepared by the reactions of the monomethyl ethers with 2-(perfluoroalkylmethyl)oxiranes in 76-97% yields. The second series CH3(OCH2CH2)nOCH2CH2CH2-CF2(CF2CF2)nCF3 (n = 1-3) possessing the non-hydroxylated spacer was synthesized from allyl methyl ethers of oligo(oxyethylene) glycols using radical additions of perfluoroalkyl iodides and subsequent selective reductions of the C-I bond in the adducts in overall yields of 23-69%. Some of the novel amphiphilic compounds displayed very low hemolytic activity to erythrocytes and excellent co-emulsifying properties on testing on perfluorodecalin/Pluronic F-68 microemulsions. 1-O-(2-Hydroxy-4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluorononyl)-d-xylitol was prepared by a novelized synthesis and employed as a standard compound in the testing.
SmI2/water/amine mediates cleavage of allyl ether protected alcohols: application in carbohydrate synthesis and mechanistic considerations.
Dahlen, Anders,Sundgren, Andreas,Lahmann, Martina,Oscarson, Stefan,Hilmersson, Goeran
, p. 4085 - 4088 (2007/10/03)
[reaction: see text]. SmI2/H2O/amine provides selective cleavage of unsubstituted allyl ethers in good to excellent yields. This method is therefore useful in deprotection of alcohols and carbohydrates.