The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo（0） compound [Et4N]3[Mo2（CO）6（μ-OC6H4OCH2C6H5）3] 1. 1 crystallizes in monoclinic, space group ...The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo（0） compound [Et4N]3[Mo2（CO）6（μ-OC6H4OCH2C6H5）3] 1. 1 crystallizes in monoclinic, space group P21/c with a = 15.359（2）, b = 18.378（3）, c = 24.952（2） A, β = 102.268（4）°, V = 6882.3（1 6） A^3, Mr = 1348.34, Z = 4, Dc = 1.301 g/cm^3, F（000） = 2832 and μ= 0.424 mm^-1 The final R = 0.0606 and wR = 0.1552 for 9396 observed reflections （I 〉 2σ（I））. I contains a [Mo2O3]^3 core in triangular bi-pyralnidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three ,μ-O atoms from C6H5CH2OC6H4O^- bridging ligands. The Mo…Mo distance is 3.30（8） A, indicating no metalmetal bonding. A formation pathway via forming a di-molybdenum（0） di-bridging OR compound [Mo2（μ-OR）2（CO）8]2 has been figured out and the reaction of Mo（CO）6 with alkoxide has also been discussed.展开更多
In an attempt to find new antitumor agents,a novel class of chromone compounds with a benzimidazole or a benzoxazole ring in positions 2 or 6 were synthesized via condensation in polyphosphoric acid(PPA) by using chro...In an attempt to find new antitumor agents,a novel class of chromone compounds with a benzimidazole or a benzoxazole ring in positions 2 or 6 were synthesized via condensation in polyphosphoric acid(PPA) by using chromone acids as the starting materials. During the preparation process,it was found that PPA could cleave the chromone ring to produce a ring-opening compound(6). The molar ratio of the chromone compound(5) to the ring-opening compound(6) varied with the change of reaction temperature and time. Based on MTT protocol,the antitumor activity of each of the compounds obtained was evaluated against three human cancer cell lines: KB(oral epidermal),A2780(ovary) and Bel7402(liver). The IC_ 50 varied from 54.7 μmol/L to more than 180 μmol/L.展开更多
A simple and highly efficient one-pot method for the construction of α-hydroxyketone phosphates from terminal alkynes and H-phosphine oxides has been developed in the presence of PhI（OAc）2 and H20. The present prot...A simple and highly efficient one-pot method for the construction of α-hydroxyketone phosphates from terminal alkynes and H-phosphine oxides has been developed in the presence of PhI（OAc）2 and H20. The present protocol provides an attractive approach to α-hydroxyketone phosphates in good to high yields, with the advantages of operation simplicity, the use of commercially available materials, broad substrate scope, high atom efficiency and good tolerance to scale-up synthesis.展开更多
Bothβ-andγ-hydroxyketone structures are important units in biologically active molecules,synthetic drugs and fine chemicals.Although there are some routes available for their manufacture from pre-functionalized grou...Bothβ-andγ-hydroxyketone structures are important units in biologically active molecules,synthetic drugs and fine chemicals.Although there are some routes available for their manufacture from pre-functionalized groups on one or two matrix molecule(s),the approaches to simply and simultaneously deposit two oxygen atoms from dioxygen into two specific C(sp^(3))positions of pure saturated hydrocarbons have rarely succeeded because they are involved in the targeted activation of three inert C–Hσbonds all at once.Here,we show that a TiO_(2)-CH_(3)CN photocatalytic suspension system enables the insertion of dioxygen into one C(sp^(3))–C(sp^(3))bond of strained cycloparaffin derivatives,by which difunctionalized hydroxyketone products are obtained in a one-pot reaction.With the cleavage event to release strain as the directional driving force,as-designed photocatalytic reaction systems show 21 examples ofβ-hydroxyketone products with 31%–76%isolated yields for three-membered ring derivatives and 5 examples ofγ-hydroxyketone products with 30%–63%isolated yields for four-membered ring substrates.^(18)O isotopic labeling experiments using^(18)O2,Ti^(18)O_(2) and intentionally added H218O,respectively,indicated that both oxygen atoms of hydroxyketone products were exclusively from dioxygen,suggesting a previously unknown H^(+)/TiO_(2)-e−catalyzed arrangement pathway of the hydroperoxide intermediate to convert dioxygen into hydroxyketone units.展开更多
In this study, Yb immobilized NaY zeolite catalyst（Yb/NaY） was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH3-TPD. The catalyst displayed good catalytic activity when applie...In this study, Yb immobilized NaY zeolite catalyst（Yb/NaY） was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH3-TPD. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of a-hydroxyketones with 1,2-diamines,and could be reused several times without any loss of catalytic activity.展开更多
The conversion of propargylic alcohols and carbon dioxide(CO_(2)) into fine chemicals suffers from issues of harsh reaction conditions and difficult catalyst recovery. To achieve efficient CO_(2)activation at low ener...The conversion of propargylic alcohols and carbon dioxide(CO_(2)) into fine chemicals suffers from issues of harsh reaction conditions and difficult catalyst recovery. To achieve efficient CO_(2)activation at low energy consumption, a silver-anchored porous aromatic framework catalyst Ag@PAF-DAB with high active phase density and CO_(2)adsorption capacity was proposed. Since Ag@PAF-DAB has the dual functions of CO_(2)capture and conversion, propargylic alcohols were completely converted into α-alkylidene cyclic carbonate or α–hydroxy ketone as high value-added product under atmospheric pressure(CO_(2), 0.1 MPa) and low silver equivalent(0.5 mol%). Notably, Ag@PAF-DAB exhibited broad substrate diversity, high stability,and excellent reusability. By applying FTIR and GC, the key to green synthetic route of α–hydroxy ketone was confirmed to lie in the further hydration of α-alkylidene cyclic carbonate.展开更多
基金This research was supported by NNSFC (No. 90203017 29733090), NBRP (2004CB7201005) and SKLSC
文摘The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo（0） compound [Et4N]3[Mo2（CO）6（μ-OC6H4OCH2C6H5）3] 1. 1 crystallizes in monoclinic, space group P21/c with a = 15.359（2）, b = 18.378（3）, c = 24.952（2） A, β = 102.268（4）°, V = 6882.3（1 6） A^3, Mr = 1348.34, Z = 4, Dc = 1.301 g/cm^3, F（000） = 2832 and μ= 0.424 mm^-1 The final R = 0.0606 and wR = 0.1552 for 9396 observed reflections （I 〉 2σ（I））. I contains a [Mo2O3]^3 core in triangular bi-pyralnidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three ,μ-O atoms from C6H5CH2OC6H4O^- bridging ligands. The Mo…Mo distance is 3.30（8） A, indicating no metalmetal bonding. A formation pathway via forming a di-molybdenum（0） di-bridging OR compound [Mo2（μ-OR）2（CO）8]2 has been figured out and the reaction of Mo（CO）6 with alkoxide has also been discussed.
文摘In an attempt to find new antitumor agents,a novel class of chromone compounds with a benzimidazole or a benzoxazole ring in positions 2 or 6 were synthesized via condensation in polyphosphoric acid(PPA) by using chromone acids as the starting materials. During the preparation process,it was found that PPA could cleave the chromone ring to produce a ring-opening compound(6). The molar ratio of the chromone compound(5) to the ring-opening compound(6) varied with the change of reaction temperature and time. Based on MTT protocol,the antitumor activity of each of the compounds obtained was evaluated against three human cancer cell lines: KB(oral epidermal),A2780(ovary) and Bel7402(liver). The IC_ 50 varied from 54.7 μmol/L to more than 180 μmol/L.
基金financial support from the National Natural Science Foundation of China(Nos.21172213,21302109,21402184,and 21572217)
文摘A simple and highly efficient one-pot method for the construction of α-hydroxyketone phosphates from terminal alkynes and H-phosphine oxides has been developed in the presence of PhI（OAc）2 and H20. The present protocol provides an attractive approach to α-hydroxyketone phosphates in good to high yields, with the advantages of operation simplicity, the use of commercially available materials, broad substrate scope, high atom efficiency and good tolerance to scale-up synthesis.
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB36000000)the National Natural Science Foundation of China(21590811,21777167,21827809)and the National Key R&D Program of China(2018YFA0209302).
文摘Bothβ-andγ-hydroxyketone structures are important units in biologically active molecules,synthetic drugs and fine chemicals.Although there are some routes available for their manufacture from pre-functionalized groups on one or two matrix molecule(s),the approaches to simply and simultaneously deposit two oxygen atoms from dioxygen into two specific C(sp^(3))positions of pure saturated hydrocarbons have rarely succeeded because they are involved in the targeted activation of three inert C–Hσbonds all at once.Here,we show that a TiO_(2)-CH_(3)CN photocatalytic suspension system enables the insertion of dioxygen into one C(sp^(3))–C(sp^(3))bond of strained cycloparaffin derivatives,by which difunctionalized hydroxyketone products are obtained in a one-pot reaction.With the cleavage event to release strain as the directional driving force,as-designed photocatalytic reaction systems show 21 examples ofβ-hydroxyketone products with 31%–76%isolated yields for three-membered ring derivatives and 5 examples ofγ-hydroxyketone products with 30%–63%isolated yields for four-membered ring substrates.^(18)O isotopic labeling experiments using^(18)O2,Ti^(18)O_(2) and intentionally added H218O,respectively,indicated that both oxygen atoms of hydroxyketone products were exclusively from dioxygen,suggesting a previously unknown H^(+)/TiO_(2)-e−catalyzed arrangement pathway of the hydroperoxide intermediate to convert dioxygen into hydroxyketone units.
基金the National Natural Science Foundation of China (No. 20802052) for financial support
文摘In this study, Yb immobilized NaY zeolite catalyst（Yb/NaY） was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH3-TPD. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of a-hydroxyketones with 1,2-diamines,and could be reused several times without any loss of catalytic activity.
基金supported by the National Key Research and Development Program of China (No. 2019YFB1504003)。
文摘The conversion of propargylic alcohols and carbon dioxide(CO_(2)) into fine chemicals suffers from issues of harsh reaction conditions and difficult catalyst recovery. To achieve efficient CO_(2)activation at low energy consumption, a silver-anchored porous aromatic framework catalyst Ag@PAF-DAB with high active phase density and CO_(2)adsorption capacity was proposed. Since Ag@PAF-DAB has the dual functions of CO_(2)capture and conversion, propargylic alcohols were completely converted into α-alkylidene cyclic carbonate or α–hydroxy ketone as high value-added product under atmospheric pressure(CO_(2), 0.1 MPa) and low silver equivalent(0.5 mol%). Notably, Ag@PAF-DAB exhibited broad substrate diversity, high stability,and excellent reusability. By applying FTIR and GC, the key to green synthetic route of α–hydroxy ketone was confirmed to lie in the further hydration of α-alkylidene cyclic carbonate.
