A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulf...A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulfonyl chloride in pyridine at 0℃ af- fords tosylates which undergo β-elimination with silica gel in dichloromethane or chloroform at room temperature, yielding olefins with high productivity.展开更多
Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interactio...Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interaction is oppos- ed by introducing a large side group.展开更多
In this paper, 5＇-O-tosyl-2,3＇-anhydrothymidine has been synthesized and its crystal structure was analyzed. The crystal belongs to the triclinic system, space group P1, with a = 5.397（2）, b = 6.1886（18）, c = 3....In this paper, 5＇-O-tosyl-2,3＇-anhydrothymidine has been synthesized and its crystal structure was analyzed. The crystal belongs to the triclinic system, space group P1, with a = 5.397（2）, b = 6.1886（18）, c = 3.507（5）A, α = 87.74（2）,β = 89.84（4）,γ = 73.79（2）°, C17H18N2O6S, Mr = 378,39, Z = 1, V = 432.8（3）A^3, Dc = 1.452 g/cm^3, F（000） = 198 and Flack = -0.11（14）. No intermolecular hydrogen bonds exist in the crystal, and the angle between benzene ring and pyrimidine planes is 32.23°.展开更多
The title compound 4-bromo-5-ethoxy-3-methyl-5-（naphthalen-l-yl）-l-tosyl-lH- pyrrol-2（5H）-one 1 （C24H22BrNO4S, Mr = 500.40） has been synthesized and its crystal structure was determined by single-crystal X-ray d...The title compound 4-bromo-5-ethoxy-3-methyl-5-（naphthalen-l-yl）-l-tosyl-lH- pyrrol-2（5H）-one 1 （C24H22BrNO4S, Mr = 500.40） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 8.8562（15）, b = 18.118（3）, c = 14.055（2）A, β = 99.855（3）^o, V= 2221.9（6）A3, Z = 4, Dc = 1.496 g/cm^3,μ= 1.975 mm^-1, 2 = 0.71073A, F（000） = 1024, R = 0.0607 and wR = 0.1371.展开更多
Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H...Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H4)3]2Cl2/2P(4-MeOC6H4)3 in the presence of K3PO4·3H2O in toluene. A variety of unsymmetrical biaryls could be obtained in good to excellent yields with1.5–3 mol% or 3–5 mol% catalyst loadings for aryl sulfamates and tosylates, respectively. In sharp contrast to the conventional nickel-catalyzed Suzuki coupling with arylboronic acids, arylsulfamates unexpectedly displayed a higher reactivity than the corresponding tosylates in coupling with diarylborinic acids catalyzed by the nickel/phosphine catalyst system.展开更多
In this paper, some new results on the selective weak interaction between Na-4-tosyl-L-arginine methyl ester hydrochloride （TAME） and adenosine-5＇-triphosphate （ATP） have been reported. Fluorescence spectrophotom...In this paper, some new results on the selective weak interaction between Na-4-tosyl-L-arginine methyl ester hydrochloride （TAME） and adenosine-5＇-triphosphate （ATP） have been reported. Fluorescence spectrophotometry and Fourier transform infrared （FT-IR） spectroscopy were used to investigate this kind of weak interaction. In fluorescence experiments, obvious fluorescence quenching phenomena were observed when TAME was added, which indicated the weak interactions between TAME and ATP. It has been identified by fluorescence titration experiments that TAME exhibited high selectivity to ATP over ADP and AMP. FT-IR spectral results showed that an ATP-TAME adduct was formed. The experimental results indicated that the interaction sites were the guanidinium group of TAME main-chain and the γ-phosphate group of ATP, and the interaction took place through hydrogen bonding and electrostatic force. In addition, the effects of metal ions on the weak interaction between ATP and TAME, or between ATP and analogues of L-arginine were studied.展开更多
We have developed an efficient method to achieve N-gem-difluorocyclopropylation of N-heterocycles with the use of gem-difluorocyclopropyl tosylate as a building block under mild conditions, gem- Difluorocyclopropyl to...We have developed an efficient method to achieve N-gem-difluorocyclopropylation of N-heterocycles with the use of gem-difluorocyclopropyl tosylate as a building block under mild conditions, gem- Difluorocyclopropyl tosylates could be easily prepared on a large scale and exhibit great stability.展开更多
An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been...An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been reported.A variety of enones underwent reduction without forming undesirable side products.High chemose-lectivity,broad functional group tolerance and good yields are the noteworthy features of this protocol.展开更多
文摘A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulfonyl chloride in pyridine at 0℃ af- fords tosylates which undergo β-elimination with silica gel in dichloromethane or chloroform at room temperature, yielding olefins with high productivity.
文摘Large crystal NPP-OTs has been obtained by growth from solution,its powder SHG efficiency is 1/3 of urea.It shows it is a new convenient approach to obtain organic second-order NLO crystal:the dipole-dipole interaction is oppos- ed by introducing a large side group.
基金the National Natural Science Foundation of China(No.20132020)
文摘In this paper, 5＇-O-tosyl-2,3＇-anhydrothymidine has been synthesized and its crystal structure was analyzed. The crystal belongs to the triclinic system, space group P1, with a = 5.397（2）, b = 6.1886（18）, c = 3.507（5）A, α = 87.74（2）,β = 89.84（4）,γ = 73.79（2）°, C17H18N2O6S, Mr = 378,39, Z = 1, V = 432.8（3）A^3, Dc = 1.452 g/cm^3, F（000） = 198 and Flack = -0.11（14）. No intermolecular hydrogen bonds exist in the crystal, and the angle between benzene ring and pyrimidine planes is 32.23°.
基金This work was supported by the National Natural Science Foundation of China (No. 20472072 and 20332060)the CAS Academician Foundation of Zhejiang Province
文摘The title compound 4-bromo-5-ethoxy-3-methyl-5-（naphthalen-l-yl）-l-tosyl-lH- pyrrol-2（5H）-one 1 （C24H22BrNO4S, Mr = 500.40） has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 8.8562（15）, b = 18.118（3）, c = 14.055（2）A, β = 99.855（3）^o, V= 2221.9（6）A3, Z = 4, Dc = 1.496 g/cm^3,μ= 1.975 mm^-1, 2 = 0.71073A, F（000） = 1024, R = 0.0607 and wR = 0.1371.
基金This work was supported by the National Natural Science Foundation of China(20972049).
文摘Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H4)3]2Cl2/2P(4-MeOC6H4)3 in the presence of K3PO4·3H2O in toluene. A variety of unsymmetrical biaryls could be obtained in good to excellent yields with1.5–3 mol% or 3–5 mol% catalyst loadings for aryl sulfamates and tosylates, respectively. In sharp contrast to the conventional nickel-catalyzed Suzuki coupling with arylboronic acids, arylsulfamates unexpectedly displayed a higher reactivity than the corresponding tosylates in coupling with diarylborinic acids catalyzed by the nickel/phosphine catalyst system.
基金Project supported by the National Natural Science Foundation of China （No. 90210027）.Acknowledgments The authors especially thank Zhide Hu in Lanzhou University for kindly allowing the use of the RF-5301PC spectrofluorophotometer （Shimadzu） in this work and Wenying He in Lanzhou University for active discussion as well as zealous help during the fluorescence experiments.
文摘In this paper, some new results on the selective weak interaction between Na-4-tosyl-L-arginine methyl ester hydrochloride （TAME） and adenosine-5＇-triphosphate （ATP） have been reported. Fluorescence spectrophotometry and Fourier transform infrared （FT-IR） spectroscopy were used to investigate this kind of weak interaction. In fluorescence experiments, obvious fluorescence quenching phenomena were observed when TAME was added, which indicated the weak interactions between TAME and ATP. It has been identified by fluorescence titration experiments that TAME exhibited high selectivity to ATP over ADP and AMP. FT-IR spectral results showed that an ATP-TAME adduct was formed. The experimental results indicated that the interaction sites were the guanidinium group of TAME main-chain and the γ-phosphate group of ATP, and the interaction took place through hydrogen bonding and electrostatic force. In addition, the effects of metal ions on the weak interaction between ATP and TAME, or between ATP and analogues of L-arginine were studied.
基金the National Natural Science Foundation of China(Nos.21032006,21172240)the 973 Program of China(No.2012CBA01200)the Chinese Academy of Sciences forfinancial support
文摘We have developed an efficient method to achieve N-gem-difluorocyclopropylation of N-heterocycles with the use of gem-difluorocyclopropyl tosylate as a building block under mild conditions, gem- Difluorocyclopropyl tosylates could be easily prepared on a large scale and exhibit great stability.
基金University Grant Commission-Basic Science Research(Order no DV-5/662/RFSMS/2012-13),New Delhi,India for financial support.
文摘An efficient,inexpensive and simple method for the reduction of variousα,β-unsaturated ketones to corre-sponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been reported.A variety of enones underwent reduction without forming undesirable side products.High chemose-lectivity,broad functional group tolerance and good yields are the noteworthy features of this protocol.
