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A new type of 1-unsymmetrical D-A cyclopropanes containing a cyclic enone motif was obtained by the desymmetrization of 1-symmetrical D-A cyclopropanes via first the Lewis acid-catalyzed O-nucleophilic ring-opening reaction with 1,3-cyclodiones followed by an organobase-promoted unexpected multistep intramolecular transformation.

1,3-Cyclohexandione derived cyclic ketals and thiol ketals were used as O- and S-nucleophiles, respectively, for the ring opening of donor-acceptor cyclopropanes catalyzed by Cu(OTf)2 and a series of functionalized alkylene glycol diethers and dithiol diethers were obtained in good to high yields under mild conditions.

Direct asymmetric synthesis of δ-hydroxy-β-ketoesters was accomplished via regio- and enantioselective aldol reactions of β-ketoesters with isatins catalyzed by cinchona alkaloid thiourea derivatives. The C-C bond formation of the reactions occurred only at the γ-position of the β-ketoesters. Reaction progress monitoring and product stability analyses under the conditions that included the catalyst indicated that the γ-position reaction products were formed kinetically. Various δ-hydroxy-β-ketoesters bearing 3-alkyl-3-hydroxyoxindole cores relevant to the development of bioactive molecules were synthesized.

1,6-Dicarbonyl compounds, representing the formal addition products of the α-position of acetophenone derivatives to donor-acceptor cyclopropanes, were synthesized in two steps via first ring opening of donor-acceptor cyclopropanes with acyclic 1,3-diketones followed by DBU catalyzed retro-Claisen-type C-C bond cleavage reactions. In the first step, acyclic 1,3-diketones selectively worked as C-nucleophiles to add to donor-acceptor cyclopropanes. In the second step, the alkyl ketone part of the ring-opening products resulting from unsymmetrical 1,3-diketones was selectively cleaved in the presence of DBU in methanol.

Densely substituted amino-functionalized benzofurans were concisely accessed via the first one-pot domino oxidation/[3+2] cyclization of a hydroquinone ester and easily accessible ynamides under mild conditions in a short time. The complex benzofurans were able to be efficiently synthesized all from simple and inexpensive starting materials in two steps.

Densely substituted amino-functionalized benzofurans were concisely accessed

Along with the acceleration of Reform and Opening up Policy in China, the connection and trade relation among China and foreign countries is getting closer and closer. Therefore, Chinese government focuses more on the exportation of Chinese local products. Among these products, tealeaf as one of the most important products with Chinese characteristics has great reputation in the world. Meanwhile, it is also an important economic crop in China. The area of tea plantations there ranks the first in the world. With the development of tea industry in China, YingshanYunwu Tea has great advantage in the world market. However, Chinese insufficient capacity in others brings a large number of problems in the exportation of this product. In this case, the problems exist in Hubei YingshanYunwu Tea and its developing conditions have been discussed in this paper. Taking the export trade of YingshanYunwu Tea in Hubei province as the research object, this paper has simply stated and analyzed the problems that exist in its exportation. At the same time, we have made SWOT analysis on YingshanYunwu Tea industry and have laid out its advantages and disadvantages, so as to find the problems in its exportation, and currently some main problems in its development are green barriers and sanitary quality, market, protecting system and fierce competition. In the end, we have also put forward some practical advice and countermeasures for export trade development of YingshanYunwu Tea. Keywords—YingshanYunwu tea; export trade; economic development