New chiral C_2-symmetrical bis(oxazoline) compounds bearing one isobutyl-, secbutyl-, benzyl- or isopropyl-substituent at the 4-position have been prepared and characterized.
Chloroamidinium salts and a-amino alcohols derived from commercially available tetraalkyl ureas and α-amino acids, respectively, can be used for the syntheses of optically active 2-（N,N-dialkylamino）oxazolines in m...Chloroamidinium salts and a-amino alcohols derived from commercially available tetraalkyl ureas and α-amino acids, respectively, can be used for the syntheses of optically active 2-（N,N-dialkylamino）oxazolines in moderate to excellent yields without any catalyst. It is a simple and mild method for the syntheses of optically active oxazolines展开更多
The title compound, C15H22N3O9P?H2O, Mr=455.36, crystallizes in orthorhombic, space group P212121, with a =9.193(2), b =14.681(3), c =15.201(3), V =2501(1)3, Z =4, Dx=1.474g/cm3, l(MoKa)=0.71073, m=0.1894mm-1, T=2991K...The title compound, C15H22N3O9P?H2O, Mr=455.36, crystallizes in orthorhombic, space group P212121, with a =9.193(2), b =14.681(3), c =15.201(3), V =2501(1)3, Z =4, Dx=1.474g/cm3, l(MoKa)=0.71073, m=0.1894mm-1, T=2991K, F(000)=960, R=0.061 and Rw=0.068 for 1899 observed reflections with I≥3s(I). The analysis results indicate that the title compound is of lyxo-configuration and the configuration at C4 is S. In the crystal state the molecule has anti conformation about glycosidic bond with the torsion angle 151.7? the sugar ring is puckered with C3-endo-C2-exo, and the conformation of the C4C5 bond is -sc.展开更多
Four 2-(α-hydroxyalkyl)-2-oxazolines and a 2-(α-hydroxy-α,α-diphenyl)-2-benzooxazole were synthesized from β-amimoalcohols and α-hydroxy carboxylic acids under microwave irradiation in the absence of a solvent.
The mass spectrometric fragmentation of 1,8-bis [ 4-substituted （oxazolin-2-yl） ] anthracenes （AnBOXes） was investigated by using mass-analyzed ion kinetic energy spectrometry under electron-impact ionization cond...The mass spectrometric fragmentation of 1,8-bis [ 4-substituted （oxazolin-2-yl） ] anthracenes （AnBOXes） was investigated by using mass-analyzed ion kinetic energy spectrometry under electron-impact ionization conditions. All the compounds could undergo a ring contraction by the loss of an RCH = CH2 molecule to form 1-oxazirinyl-8-（oxazolin- 2-yl） anthracene ions, which could further lose an R radical, followed by the loss of oxazoline. These ions could also eliminate an R radical and subsequently undergo ring-contraction rearrangements to lose a CHCH2O fragraent and an epoxide molecule, respectively. The ions that are formed could further lose CHCH2O and CH2 = CH fragments. Several ring-contraction rearrangements of the oxazoline ring were observed under electron-impact ionization conditions.展开更多
The compound C12H19Cl2N20·1/2H2O was obtained as the by-product of synthesizing silylene-bridged amino-oxazoline, and its structure was determined by X-ray diffraction. The crystal is of triclinic, space group P1...The compound C12H19Cl2N20·1/2H2O was obtained as the by-product of synthesizing silylene-bridged amino-oxazoline, and its structure was determined by X-ray diffraction. The crystal is of triclinic, space group P1, with a = 12.132（5）, b = 12.231（5）, c = 16.435（6） A^°, α = 97.485（8）, β = 106.106（7）,γ = 98.538（7）°, λ = 0.7103 A^°, V = 2279.0（15）A^°3, Z = 6, Dc = 1.251 g/cm^3, Mr = 286.19, F（000） = 906, R = 0.0846 and wR = 0.2295 for 6290 observed reflections with I 〉 2σ（I）. It is a Cl-salt. The compound was composed of phenyl, amino ion and amido derivatives. The aforementioned components were held together into a complicated three-dimensional network through three types of hydrogen bonding interactions.展开更多
By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with e...By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution.展开更多
基金the Foundation for Academic Leader by the Education Department of Hunan province.
文摘New chiral C_2-symmetrical bis(oxazoline) compounds bearing one isobutyl-, secbutyl-, benzyl- or isopropyl-substituent at the 4-position have been prepared and characterized.
文摘Chloroamidinium salts and a-amino alcohols derived from commercially available tetraalkyl ureas and α-amino acids, respectively, can be used for the syntheses of optically active 2-（N,N-dialkylamino）oxazolines in moderate to excellent yields without any catalyst. It is a simple and mild method for the syntheses of optically active oxazolines
基金This project was supported by the Foundation for University Key Teachers by the Ministry of Education
文摘The title compound, C15H22N3O9P?H2O, Mr=455.36, crystallizes in orthorhombic, space group P212121, with a =9.193(2), b =14.681(3), c =15.201(3), V =2501(1)3, Z =4, Dx=1.474g/cm3, l(MoKa)=0.71073, m=0.1894mm-1, T=2991K, F(000)=960, R=0.061 and Rw=0.068 for 1899 observed reflections with I≥3s(I). The analysis results indicate that the title compound is of lyxo-configuration and the configuration at C4 is S. In the crystal state the molecule has anti conformation about glycosidic bond with the torsion angle 151.7? the sugar ring is puckered with C3-endo-C2-exo, and the conformation of the C4C5 bond is -sc.
文摘Four 2-(α-hydroxyalkyl)-2-oxazolines and a 2-(α-hydroxy-α,α-diphenyl)-2-benzooxazole were synthesized from β-amimoalcohols and α-hydroxy carboxylic acids under microwave irradiation in the absence of a solvent.
基金Supported by the National Natural Science Foundation of China(No. 20272002).
文摘The mass spectrometric fragmentation of 1,8-bis [ 4-substituted （oxazolin-2-yl） ] anthracenes （AnBOXes） was investigated by using mass-analyzed ion kinetic energy spectrometry under electron-impact ionization conditions. All the compounds could undergo a ring contraction by the loss of an RCH = CH2 molecule to form 1-oxazirinyl-8-（oxazolin- 2-yl） anthracene ions, which could further lose an R radical, followed by the loss of oxazoline. These ions could also eliminate an R radical and subsequently undergo ring-contraction rearrangements to lose a CHCH2O fragraent and an epoxide molecule, respectively. The ions that are formed could further lose CHCH2O and CH2 = CH fragments. Several ring-contraction rearrangements of the oxazoline ring were observed under electron-impact ionization conditions.
文摘The compound C12H19Cl2N20·1/2H2O was obtained as the by-product of synthesizing silylene-bridged amino-oxazoline, and its structure was determined by X-ray diffraction. The crystal is of triclinic, space group P1, with a = 12.132（5）, b = 12.231（5）, c = 16.435（6） A^°, α = 97.485（8）, β = 106.106（7）,γ = 98.538（7）°, λ = 0.7103 A^°, V = 2279.0（15）A^°3, Z = 6, Dc = 1.251 g/cm^3, Mr = 286.19, F（000） = 906, R = 0.0846 and wR = 0.2295 for 6290 observed reflections with I 〉 2σ（I）. It is a Cl-salt. The compound was composed of phenyl, amino ion and amido derivatives. The aforementioned components were held together into a complicated three-dimensional network through three types of hydrogen bonding interactions.
基金Supported by the National Natural Science Foundation of China(Grant no.59503002)and Polymer Physics Laboratory of Changchun Institute of Applied Chemistry,Chinese Academy of Sciences
文摘By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution.
