The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the amm...The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.展开更多
The title compound （-）-N-[（3R）-3-cyclohexyl]-3-phenylpropananoyl]bornane-10,2sultam （C 25 H 35 NO 3 S,M r=429.60）,a derivative of camphorsultam,crystallizes in the monoclinic space group P2 1 /c with a=10.3301（...The title compound （-）-N-[（3R）-3-cyclohexyl]-3-phenylpropananoyl]bornane-10,2sultam （C 25 H 35 NO 3 S,M r=429.60）,a derivative of camphorsultam,crystallizes in the monoclinic space group P2 1 /c with a=10.3301（7）,b=19.4040（13）,c=11.8106（8）,β=100.5580（10）°,V=2327.3（3） 3,Z=4,D c=1.226 g/cm 3,λ=0.71073,μ（MoKα）=0.165 mm-1 and F（000）=928.X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat form （Fig.1）.The planes constructed by （C（4）,C（5）,C（6）,C（7）） and （C（7）,C（8）,C（9）,C（4）） form a dihedral angle of 69.5°.The C（1）-C（2）-C（3） plane forms dihedral angles to the aforementioned planes of 89.8（1） and 85.9（3）°,respectively.And molecules are linked via hydrogen bonding （C-H···N/O） interactions.展开更多
Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction...Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction analysis. The crystal of C 16 O 3SNH 25 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 734 6(7) nm, b =1 142 7(3) nm, c =2 009 7(3) nm, β =90 00°, V =1 686 9 nm 3, Z=4, D c=1 250 g/cm 3, μ =1 926 cm -1 and F (000)=672. The crystal of C 15 O 3SNH 23 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 738 2(2) nm, b =0 921 6(1) nm, c =2 280 9(8) nm, β =90 00°, V =1 551 7 nm 3, Z =4, D c=1 273 g/cm 3, μ =2 504 cm -1 and F (000)=640. The structural characteristics with respect to the potential utility for the stereoselective Michael addition reaction of the N enoyl group are discussed.展开更多
potential chiral auxilliary, (+)-camphor derived N-propionyl sultam, wassynthesized from (+ )-camphor-10-sulphonyl chloride in four steps with enan-tiomerical purity. The molecular and crystal structures of the title ...potential chiral auxilliary, (+)-camphor derived N-propionyl sultam, wassynthesized from (+ )-camphor-10-sulphonyl chloride in four steps with enan-tiomerical purity. The molecular and crystal structures of the title compound weredetermined by single crystal diffraction analysis. The crystal belongts to monoclin-ic , space group P2_1 with cell dimentions a= 1. 0502(4) , b= 0. 7252(1 ) , c= 0. 9363(2) nm, β= 108. 3(5) , V = 0. 677 nm￣3, F(000) = 292 and Z= 2. The structuralcharacteristics with respect to the potential utility for the stereoselective alkylationat a-carbon of the N-propionyl group are discussed and explained based on ￣1H-, ￣(13)C-NMR. MS and X-ray analysis.展开更多
The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G＊ leve...The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G＊ level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo- β-sultam and the most favorite pathway is the breaking of C–N bond instead of S–N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.展开更多
The chiral molecule （＋）-N-[（3S）-3-（4-fluorophenyl）heptanoyl]bornane-10,2-sultam （C23H32FNO3S, Mr = 421.56）, a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the...The chiral molecule （＋）-N-[（3S）-3-（4-fluorophenyl）heptanoyl]bornane-10,2-sultam （C23H32FNO3S, Mr = 421.56）, a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the orthorhombic space group P212121 with a = 7.9044（11）, b = 11.6680（16）, c = 24.899（3） , V = 2296.4（5） 3, Z = 4, Dc = 1.219 Mg/m3, λ = 0.71073 , μ（MoKα） = 0.172 mm-1 and F（000） = 904. X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat conformation （Fig. 1）. The planes constructed by （（C6）, （C7）, （C8）, （C9）） and （（C4）, （C5）, （C6）, （C9）） form a dihedral angle of 70.3（3）°. The plane of （C1）-（C2）-（C3） forms dihedral angles to the aforementioned planes of 85.9（4） and 89.5（4）°, respectively. The molecules are linked via C-H···O/F interactions.展开更多
R ) and ( S ) 4 Methyl 1 nonanol, the sex attractant of the yellow mealworn( Tenebrio molitor L. ), were synthesized from bornane 10,2 sultam via asymmetric alkylation of N acylbornane 10,2 sultam with alkyl iodide, r...R ) and ( S ) 4 Methyl 1 nonanol, the sex attractant of the yellow mealworn( Tenebrio molitor L. ), were synthesized from bornane 10,2 sultam via asymmetric alkylation of N acylbornane 10,2 sultam with alkyl iodide, reductive cleavage with LiAlH 4, bromination with HBr and reaction of organocuprate reagent with ethylene oxide in the presence of BF 3·Et 2O. The enantiomeric excess of the total syntheses was over 97%e.e..展开更多
Enantiomerically pure sultams (-)-2, (+)-3 and (+)-4 were synthesized.Their uses as new chiral auxiliaries in asymmetric Diels-Alder reactions with diastereoselectivity up to 99∶1 are presented. The relationship betw...Enantiomerically pure sultams (-)-2, (+)-3 and (+)-4 were synthesized.Their uses as new chiral auxiliaries in asymmetric Diels-Alder reactions with diastereoselectivity up to 99∶1 are presented. The relationship between the structure of chiral sultam and the effectiveness of asymmetric induction in Diels-Alder reactions are also discussed.展开更多
文摘The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.
基金sponsored by the Science Foundation of Ministry of Education for the New Teacher at the University of China (No. 20070511006)the Research Initiation Funds of Huazhong Agricultural University (No. 52204-09057)
文摘The title compound （-）-N-[（3R）-3-cyclohexyl]-3-phenylpropananoyl]bornane-10,2sultam （C 25 H 35 NO 3 S,M r=429.60）,a derivative of camphorsultam,crystallizes in the monoclinic space group P2 1 /c with a=10.3301（7）,b=19.4040（13）,c=11.8106（8）,β=100.5580（10）°,V=2327.3（3） 3,Z=4,D c=1.226 g/cm 3,λ=0.71073,μ（MoKα）=0.165 mm-1 and F（000）=928.X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat form （Fig.1）.The planes constructed by （C（4）,C（5）,C（6）,C（7）） and （C（7）,C（8）,C（9）,C（4）） form a dihedral angle of 69.5°.The C（1）-C（2）-C（3） plane forms dihedral angles to the aforementioned planes of 89.8（1） and 85.9（3）°,respectively.And molecules are linked via hydrogen bonding （C-H···N/O） interactions.
文摘Two potential chiral auxiliaries, N (E ) enoyl(-) bornane 10,2 sultams, were synthesized from (-) bornane 10,2 sultams. The molecular crystal structures of the title compounds were determined by diffraction analysis. The crystal of C 16 O 3SNH 25 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 734 6(7) nm, b =1 142 7(3) nm, c =2 009 7(3) nm, β =90 00°, V =1 686 9 nm 3, Z=4, D c=1 250 g/cm 3, μ =1 926 cm -1 and F (000)=672. The crystal of C 15 O 3SNH 23 belongs to a rhombic system, the space group is P 2 12 12 1 with cell parameters: a =0 738 2(2) nm, b =0 921 6(1) nm, c =2 280 9(8) nm, β =90 00°, V =1 551 7 nm 3, Z =4, D c=1 273 g/cm 3, μ =2 504 cm -1 and F (000)=640. The structural characteristics with respect to the potential utility for the stereoselective Michael addition reaction of the N enoyl group are discussed.
文摘potential chiral auxilliary, (+)-camphor derived N-propionyl sultam, wassynthesized from (+ )-camphor-10-sulphonyl chloride in four steps with enan-tiomerical purity. The molecular and crystal structures of the title compound weredetermined by single crystal diffraction analysis. The crystal belongts to monoclin-ic , space group P2_1 with cell dimentions a= 1. 0502(4) , b= 0. 7252(1 ) , c= 0. 9363(2) nm, β= 108. 3(5) , V = 0. 677 nm￣3, F(000) = 292 and Z= 2. The structuralcharacteristics with respect to the potential utility for the stereoselective alkylationat a-carbon of the N-propionyl group are discussed and explained based on ￣1H-, ￣(13)C-NMR. MS and X-ray analysis.
基金This work was supported by the National Natural Science Foundation of China (No. 20373034 and 20603030)Post-doctor Research Foundation of Shandong Province (No. 200601007)
文摘The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G＊ level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo- β-sultam and the most favorite pathway is the breaking of C–N bond instead of S–N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.
基金the Student Research Fund of Huazhong Agricultural University (11094)the National Undergraduate Innovational Experimentation Program (1210504018)the National Natural Science Foundation of China (31101467)
文摘The chiral molecule （＋）-N-[（3S）-3-（4-fluorophenyl）heptanoyl]bornane-10,2-sultam （C23H32FNO3S, Mr = 421.56）, a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the orthorhombic space group P212121 with a = 7.9044（11）, b = 11.6680（16）, c = 24.899（3） , V = 2296.4（5） 3, Z = 4, Dc = 1.219 Mg/m3, λ = 0.71073 , μ（MoKα） = 0.172 mm-1 and F（000） = 904. X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat conformation （Fig. 1）. The planes constructed by （（C6）, （C7）, （C8）, （C9）） and （（C4）, （C5）, （C6）, （C9）） form a dihedral angle of 70.3（3）°. The plane of （C1）-（C2）-（C3） forms dihedral angles to the aforementioned planes of 85.9（4） and 89.5（4）°, respectively. The molecules are linked via C-H···O/F interactions.
文摘R ) and ( S ) 4 Methyl 1 nonanol, the sex attractant of the yellow mealworn( Tenebrio molitor L. ), were synthesized from bornane 10,2 sultam via asymmetric alkylation of N acylbornane 10,2 sultam with alkyl iodide, reductive cleavage with LiAlH 4, bromination with HBr and reaction of organocuprate reagent with ethylene oxide in the presence of BF 3·Et 2O. The enantiomeric excess of the total syntheses was over 97%e.e..
文摘Enantiomerically pure sultams (-)-2, (+)-3 and (+)-4 were synthesized.Their uses as new chiral auxiliaries in asymmetric Diels-Alder reactions with diastereoselectivity up to 99∶1 are presented. The relationship between the structure of chiral sultam and the effectiveness of asymmetric induction in Diels-Alder reactions are also discussed.
