N-(Dehydroabietyl)maleamic acid was synthesized from dehydroabietylamine and maleic anhydride.Its structure was characterized by IR,1 H-and 13 C-NMR spectra.The stereo structure of the title compound was also unambi...N-(Dehydroabietyl)maleamic acid was synthesized from dehydroabietylamine and maleic anhydride.Its structure was characterized by IR,1 H-and 13 C-NMR spectra.The stereo structure of the title compound was also unambiguously confirmed by X-ray crystal structure analysis.The white crystal crystallizes in the monoclinic system,space group P2 1 with a=12.075(2),b=10.377(2),c=17.840(4),β=100.31(3) °,V=2199.3(8) 3,R=0.0618 and wR=0.1437.Two crystallographically independent molecules with different conformations co-exist in the unit.In each molecule,the two cyclohexane rings form a trans ring junction with chair and half-chair conformations,respectively.The C=C double bond between two carbonyl groups is in a Z configuration.Intermolecular and intramolecular hydrogen bonds coexist to stabilize the structure.展开更多
FT infrared spectrometer was used to obtain a series of infrared spectra at various temperatures of pentaerythritol(PE)、pentaglycerine(PG)、neopentylglycol(NPG) and their binary mixtures.The shifts of -OH absorption ...FT infrared spectrometer was used to obtain a series of infrared spectra at various temperatures of pentaerythritol(PE)、pentaglycerine(PG)、neopentylglycol(NPG) and their binary mixtures.The shifts of -OH absorption peak reveal the solid solid phase transition mechanisms and the connection of wave number shifts with temperature and enthalpies of phase transition.The solid solid phase transitions of the three polyols and their binary mixtures are known to transform from a low symmetric layered crystal structure to a highly symmetric face centered cubic structure.Experimental results support a mechanism which involves reversible breaking of nearest neighbor hydrogen resonance bonds in the molecular crystals at the transformation temperature.Infrared spectra show reversible increase in the wave number of the absorption peak of -OH groups with reversible breaking of the hydrogen bonds.This is in agreement with the experimental results of X ray diffraction and thermal analysis.展开更多
基金supported by the grants from Fundamental Research Foundation of the Central Commonwealth Institute of the Chinese Academy of Forestry (CAFYBB2008021)the Natural Science Foundation of Jiangsu Province (BK2008088)the National Natural Science Foundation of China (30800871)
文摘N-(Dehydroabietyl)maleamic acid was synthesized from dehydroabietylamine and maleic anhydride.Its structure was characterized by IR,1 H-and 13 C-NMR spectra.The stereo structure of the title compound was also unambiguously confirmed by X-ray crystal structure analysis.The white crystal crystallizes in the monoclinic system,space group P2 1 with a=12.075(2),b=10.377(2),c=17.840(4),β=100.31(3) °,V=2199.3(8) 3,R=0.0618 and wR=0.1437.Two crystallographically independent molecules with different conformations co-exist in the unit.In each molecule,the two cyclohexane rings form a trans ring junction with chair and half-chair conformations,respectively.The C=C double bond between two carbonyl groups is in a Z configuration.Intermolecular and intramolecular hydrogen bonds coexist to stabilize the structure.
文摘FT infrared spectrometer was used to obtain a series of infrared spectra at various temperatures of pentaerythritol(PE)、pentaglycerine(PG)、neopentylglycol(NPG) and their binary mixtures.The shifts of -OH absorption peak reveal the solid solid phase transition mechanisms and the connection of wave number shifts with temperature and enthalpies of phase transition.The solid solid phase transitions of the three polyols and their binary mixtures are known to transform from a low symmetric layered crystal structure to a highly symmetric face centered cubic structure.Experimental results support a mechanism which involves reversible breaking of nearest neighbor hydrogen resonance bonds in the molecular crystals at the transformation temperature.Infrared spectra show reversible increase in the wave number of the absorption peak of -OH groups with reversible breaking of the hydrogen bonds.This is in agreement with the experimental results of X ray diffraction and thermal analysis.