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nanohero

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[交流] How abundant my day is!

Blink of an eye, I am already a student of postgraduate two. It is the real time that a daily plan was made in order that good habits can be formed. In the morning, after breakfast, entering the laboratory, the first thing I must do is open my notebook computer, then watch my email to keep up with the information of frontier science and technology, which is followed by starting my experiments. In the afternoon, a nap is necessary for my abundent energy. After the nap, four hydrophobic glass should be prepared for the next experiments. It comes to supper which is so hard to know what to eat in the university canteen, which is usually met by us students in the university. At the beginning of my night, I need take a rest after so busy day time by watching TV, communicating with my classmates, listening to the songs and enjoy them with the person who will enjoy with me which is my favirate. Then I need make some supplemented experiments and some preparation for the next day. How abundant the day is!

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Communicationmakesthewordperfect.

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张冬凯-

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The addition of nitrogen oxides and other sources of NO2 across the double bonds of alkenes is an important route to nitro compounds. Alkenes react with dinitrogen tetroxide in the presence of oxygen to form a mixture of vic-dinitro(a), β-nitro-nitrate ester (b) and β-nitro-nitrite ester(c) compounds; the nitrite ester being oxidized to the nitrate ester in the presence of excess dinitrogen tetroxide. A steam of oxygen gas is normally bubbled through the reaction mixture to expel nitrous oxide formed during the reaction and so prevent more complex being formed. These reactions can be synthetically useful for the synthesis of vic-dinitroalkanes because nitrate and nitrous ester by -products are chemically unstable and are readily hydrolyzed to the corresponding β-nitro alcohol on treatment with methanol.
1,2-Dinitroethane and 1,2-dinitrocyclohexane can be formed in this way from corresponding alkenes in 42% and 37% yield respectively.
the addition of dinitrogen tetroxide across the double bonds of electrons deficient fluorinated alkenes is a particularly useful route to vic-dinitro compounds where yields are frequently high, tetrafluoroethylene gives a 53% yield of 1,2-dinitro-1,1,2,2-tetrafluoroethane.