(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the correspo...(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the corresponding 1, 3-enynylsulfides 3 stereospecifically in high yields.展开更多
(E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically af...(E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2-sulfonyl-substituted 1,3-enynes 3 in high yields.展开更多
The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222...The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222(6), b = 16.2594(5), c = 16.4885(5) A, β = 94.9900(10)°, V= 4359.3(2) A^3, Z = 4, Mn3C46N8O12H32, Mr = 1053.62, Dc = 1.605 g/cm^3, F(000) = 2140 and μ(MoKa) = 0.932 mm^-1. The structure was refined to R = 0.0578 and wR = 0.1061 for 4795 observed reflections (I 〉 2σ(I)). The oxalate anions behave as the bridging ligand and link two manganese atoms repeatedly to form infinite one-dimensional chains which further extend into a two-dimensional network by bridging 4,4′-bpy ligands.展开更多
Aging of a solid composite propellant containing HTPB/AP/AL was performed in order to validate the conformance of the accelerated aging data to the Arrhenius law. The main objective of the work was to examine the infl...Aging of a solid composite propellant containing HTPB/AP/AL was performed in order to validate the conformance of the accelerated aging data to the Arrhenius law. The main objective of the work was to examine the influence of the aziridine bonding agents family on the propellant aging. Aging of the prepared propellant samples was conducted as follows: 1. Four samples, one free of bonding agents, and three containing aziridine based bonding agents MAPO,HX-752, MAT4 were aged at 65°C. 2. Another four samples based on HX-752, MAT4 with different curing agents were aged at 65°C. The measured mechanical properties of the free bonding agent propellant samples were very far from the specifications and this illustrates the importance of the bonding agents in both the preparation and the aging phases.The prepared bonding agent 'MAT4' gave remarkable improvements of the mechanical properties comparing with HX-752 and MAPO. The aziridine bonding agents family inhibited the rate of decomposition of the propellant during the aging periods and supported the propellant matrix against decomposition at the elevate temperatures. Using of HMDI as curing agent gave slight better mechanical properties to the IPDI.展开更多
基金We thank the National Natural Science Foundation of China (Project 20462002) Natural Science Foundation of Jiangxi Province (Project 0420015) for financial support.
文摘(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the corresponding 1, 3-enynylsulfides 3 stereospecifically in high yields.
基金the National Natural Science Foundation of China(No.20462002)Natural Science Foundation of Jiangxi Province(No.0420015)for financial support.
文摘(E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2-sulfonyl-substituted 1,3-enynes 3 in high yields.
文摘The title complex, [Mn3(μ-oxalate)3(μ-4,4′-bpy)2(4,4′-bpy)2]n, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in the monoclinic, space group P2 1/c with a = 16.3222(6), b = 16.2594(5), c = 16.4885(5) A, β = 94.9900(10)°, V= 4359.3(2) A^3, Z = 4, Mn3C46N8O12H32, Mr = 1053.62, Dc = 1.605 g/cm^3, F(000) = 2140 and μ(MoKa) = 0.932 mm^-1. The structure was refined to R = 0.0578 and wR = 0.1061 for 4795 observed reflections (I 〉 2σ(I)). The oxalate anions behave as the bridging ligand and link two manganese atoms repeatedly to form infinite one-dimensional chains which further extend into a two-dimensional network by bridging 4,4′-bpy ligands.
文摘Aging of a solid composite propellant containing HTPB/AP/AL was performed in order to validate the conformance of the accelerated aging data to the Arrhenius law. The main objective of the work was to examine the influence of the aziridine bonding agents family on the propellant aging. Aging of the prepared propellant samples was conducted as follows: 1. Four samples, one free of bonding agents, and three containing aziridine based bonding agents MAPO,HX-752, MAT4 were aged at 65°C. 2. Another four samples based on HX-752, MAT4 with different curing agents were aged at 65°C. The measured mechanical properties of the free bonding agent propellant samples were very far from the specifications and this illustrates the importance of the bonding agents in both the preparation and the aging phases.The prepared bonding agent 'MAT4' gave remarkable improvements of the mechanical properties comparing with HX-752 and MAPO. The aziridine bonding agents family inhibited the rate of decomposition of the propellant during the aging periods and supported the propellant matrix against decomposition at the elevate temperatures. Using of HMDI as curing agent gave slight better mechanical properties to the IPDI.