Studies On The Electrochemical Green Synthesis Of C-C And C-N Bonds

Organic electrochemistry synthesis, as well known as organic electrosynthesis, is a kind of interdisciplinary subjects of combination of organic synthesis and electrochemistry. The major researches focus on electrons transfer of organic molecule or catalyst between the surface of "electrode and electrolyte", mutual transformation between electric energy and chemical energy and even the principles of the breakage of old bonds and formation of the new bonds.With the rapid development of green organic synthesis, chemists always devote their efforts to make the reaction condition milder, the procedure of reaction simpler, more efficiency and environment friendly. Compared with the traditional oxidants and reductants, electrons are environment friendly, post processing simple and mild, which more meeting the requirement of sustainable development and low carbon economy.This thesis focuses on the studies on the electrochemical green synthesis of C-C and C-N bonds. There are three parts included in this thesis. The first part is the review of the recent progress and development direction of organic electrosynthesis at home and abroad. The second part involves the organic electrosynthesis of homoallylic alcohols, amidines and oximes. In the third part we study the preparation of different shape of tin and characterization.First, based on the existing methods for synthesis of homoallylic alcohols, we realize paired electrosynthesis of carbonyl compounds and homoallylic alcohols, then we also realize one-pot tandem electrosynthsis of homoallylic alcohols from alcohols. At anode, alcohols are oxidized to form carbonyl compounds, while metallic tin is deposited at cathode. These electrolytic products reacted with the allyl bromide gives the homoallylic alcohols. Compared with the single electrode reaction, in which only working electrode is applied, this method improves the efficiency of electric energy. Meanwhile the scope of reaction substrate is broadened from aldehydes to alcohols with mild conditions.Second, we study the electrochemical imidation of aliphatic amines via anodic oxidation. At anode, the aliphatic amines are oxidized to form intermediate enamines, which reacted with sulfonyl azides to produce amidines via1,3-dipolar cycloaddition. Traditional catalysts for this reaction are completely avoided. The types of aliphatic amines are broadened from tertiary amines to primary and secondary amines. The transformation is completed quantatively under mild condition, which provide this method with high industrial value.Next, we further realize the electrochemical one-pot tandem synthesis of oximes from alcohols with KNO3both as electrolyte and nitrogen source. At anode, the alcohols are oxidized to form carbonyl compounds, while metallic tin is deposited at cathode. The deposited tin mediated the KNO3to in-situ produce hydroxylamine. These electrolytic products mixed to produce the oximes. The results show that the hollow tin spheres have high catalytic reactivity. This reaction broadens the type of nitrogen source of the oximation.At last, we tune the shape of metallic tin and characterization. We get different shape of metallic tin, such as hollow sphere, star, rod and irregular polyhedron with adjustment of the concentration of SnCl2. Moreover, we try the preparation of polymer stabilized nano Sn. The diameter is around5nm.In conclusion, we combine the organic chemistry with electrochemistry to develop novel methods for the formation of C-C and C-N bonds. These methods maintain the properties of mild conditions, simple procedure, broadening the scope of reaction substrates or catalysts and high industrial value, which provide new thoughts and direction for the development of green organic synthesis.