L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

Production of Chiral Aromatic Alcohol by Asymmetric Reduction with Vegetable Catalyst

Chiral aromatic alcohols are the key chiral building block for many important enantiopure pharmaceu-ticals. In this work,we studied asymmetric reduction of prochiral aromatic ketone to produce the corresponding chiral alcohol using vegetables as the biocatalyst. Acetophenone was chosen as the model substrate. The results in-dicate that acetophenone can be reduced to the corresponding chiral alcohols with high enantioselectivity by the chosen vegetables,i.e. apple(Malus pumila),carrot(Daucus carota),cucumber(Cucumis sativus),onion(Allium cepa),potato(Soanum tuberosum),radish(Raphanus sativus),and sweet potato(Ipomoea batatas) . In the reaction,R-1-phenylethanol is produced with apple,sweet potato and potato as the catalyst,while S-1-phenylethanol is the product with the other vegetables as the catalyst. In term of the enantioselectivity and reaction yield,carrot(D. ca-rota) is the best catalyst for this reaction. Furthermore,the reaction characteristics were studied in detail using car-rot(D. carota) as the biocatalyst. The effects of various factors on the reaction were investigated and the optimal reaction conditions were determined. Under the optimal reaction conditions(reaction time 50 h,substrate concen-tration 20 mmol·L-1,reaction temperature 35 °C and pH 7),95% of e.e.(to S-1-phenylethanol) and 85% chemical yield can be obtained. This work extends the biocatalyst for the asymmetric reduction reaction of prochiral aromatic ketones,and provides a novel potential route to produce enantiopure aromatic alcohols.

Study on the Ability of Coriander Water Purification

In order to study on the water purification ability of coriander, according to the material of Iris pseudacorus, Pontederia cordata, Thalia dealbata, coriander, Lythrum salicaria as the research object, the paper carries on the analysis and comparison of water purification ability under greenhouse conditions in the 3~6 month period. The results showed： N, P content of coriander organizational changes before and after the test. Physiological responses of different plants, coriander is not sensitive to the physiological responses to stress of sewage, sewage adaptability is relatively strong. Judging from the effect of different plants to the water, then spent force has highest the removal rate for TN, coriander has the strongest absorption capacity for TP, water purification plant is excellent