Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690....Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690.64, a=28.652(5), b=14.108(4), c=7.424(3) ;β=90.09(1); V=3001(2)~3; Z=4, Dc=1.53g/cm^3. Final R factor is 0.041. The structure consists of a discrete cation [Co~ⅢCl_2(py)_4]^+ and an anion [Co~Ⅱ Cl_3(py)]^-. The Co~Ⅲ ion is coordinated by two Cl^- and four pyridine nitrogen atoms to form an octahedral geometry, and Co~Ⅱ is coordinated by three Cl^- and one pyridine nitrogen atom to form the apices of a tetrahedron. The variable-temperature magnetic susceptility measurement shows no magnet-exchange interaction between Co~Ⅲ and Co~Ⅱ ions.展开更多
The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that...The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.展开更多
文摘Complex salt Co_2Cl_5(py)_5 (py=pyridine) was obtained by the reaction of CoCl_2·6H_2O with Bu_4NMnO_4 in pyridine in the presence of benzoic acid. It is monoclinic and crystallizes in space group P2_1/n, fw=690.64, a=28.652(5), b=14.108(4), c=7.424(3) ;β=90.09(1); V=3001(2)~3; Z=4, Dc=1.53g/cm^3. Final R factor is 0.041. The structure consists of a discrete cation [Co~ⅢCl_2(py)_4]^+ and an anion [Co~Ⅱ Cl_3(py)]^-. The Co~Ⅲ ion is coordinated by two Cl^- and four pyridine nitrogen atoms to form an octahedral geometry, and Co~Ⅱ is coordinated by three Cl^- and one pyridine nitrogen atom to form the apices of a tetrahedron. The variable-temperature magnetic susceptility measurement shows no magnet-exchange interaction between Co~Ⅲ and Co~Ⅱ ions.
基金the Science and Technology Research Project for University of Liaoning Province(No.20060038)for the generous financial support.
文摘The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.
