Thus, 3 mol of Ethyl acetoacetate were treated with 2 mol of formaldehyde to yield 80% of I.

用2摩爾的甲醛處理3摩爾的乙酰乙酸乙酯可得到80%的I72式免费A片视频。

The synthesis of fructone from ethyl acetoacetate and ethylene glycol using sulfonated activated carbon as solid acid catalyst was investigated.

以活性炭磺化制得新型固體磺酸磺化炭為催化劑国产a片久久精品，對乙酰乙酸乙酯和乙二醇合成蘋果酯的催化工藝進行了系統(tǒng)研究。

Various reaction parameters such as ratio of ethyl acetoacetate to ethylene glycol,catalyst amount,reaction time and water-carrying reagent amount were studied.

討論了酯醇比欧美人与禽ZOZOXXXX另类、催化劑用量浓毛妓女中国HD、反應(yīng)時間、帶水劑用量對酯化率的影響欧美性爱视频吧。最佳反應(yīng)條件為：n：n=1：1.8国产精品一级艳片无码，催化劑用量為乙酰乙酸乙酯質(zhì)量的2%，帶水劑用量為20mL黄色一级免费播放网站，反應(yīng)時間3h亚洲乱伦视频网站。

_6P_2W_(17)VO_(62) catalyst was prepared and characterized by FTIR,and synthesis of fraistone over as-synthesized catalyst from ethyl acetoacetate and 1,2-propylene glycol was investigated.

制備了Dawson型磷鎢釩酸銨催化劑，用FT-IR分析方法對催化劑進行了結(jié)構(gòu)表征，并以乙酰乙酸乙酯與1老熟女毛多一区二区，2-丙二醇為原料催化合成了蘋果酯-B国产一级视频69欧美一级。

Supported 12-Phosphotungstic Acid and Its Salts as Catalysts for the Synthesis of Fructone and Fructone-B;2. Their catalytic activities were measured by synthesis of fructone-B from ethyl acetoacetate and 1,2-propanediol.

制備了一系列以脫鋁超穩(wěn)Y沸石為載體的磷鎢酸及其銫鹽催化劑，考察了催化劑在以乙酰乙酸乙酯和1国产毛多水多女人A片，2-丙二醇為原料催化合成草莓酯反應(yīng)過程中的性能久久丝袜美腿国产精品。

This thesis consists of four chapters:Chapter 1: Michael addition of chalcones with active methylene compounds such as diethyl malonate, ethyl acetoacetate and nitromethane catalyzed by potassium hydroxide in anhydrous ethanol results Michael adducts in 72-98% yield under ultrasound irradiation in 25-150min.

第一章：研究了超聲輻射下，氫氧化鉀催化的查耳酮與活潑亞甲基化合物如丙二酸二乙酯8x8cmo永久免费视频、乙酰乙酸乙酯和硝基甲烷的邁克爾反應(yīng)欧美天天摸天天添人人喊。

Optically active ethyl-3-hydroxybutyrate,a useful chiral synthon,was prepared by stereoselective reduction of ethyl acetoacetate of the bread yeast in organic solvent.

利用面包酵母在非水相中不對稱還原乙酰乙酸乙酯，制備了光學(xué)活性的手性化合物S-3-羥基丁酸乙酯久久久久精品无码。

Could keep above 95% in the fixed beds. In order to achieve high stereo-selectivity with yeast, ethyl acetoacetate was used as the model substrate,and a novel approach was proposed to selectively inhibit R-enzymes in yeast before reaction.

以乙酰乙酸乙酯為模型底物日韩黄片毛片，以丙烯酸、乙醚黄色网站.www、二甲基亞砜亚洲三级片网址、丙烯酰胺、正己烷等有機溶劑選擇性地抑制酵母中R型酶久久精品视频色，提高反應(yīng)立體選擇性日本XXWWXXWW视频免费。

Methyl-l, 3-oxazine-2,4-dione are prepared from ethyl acetoacetate and ethyl carbamate at 140 for 6h, catalysted by zinc acetate, giving to 48.8% yields which is 33% more than the literature value.

選用醋酸鋅作催化劑，使乙酰乙酸乙酯與氨基甲酸酯在140℃反應(yīng)6h欧美成A人片在线观看完整版，合成6-甲基-1国产精品综合日本欧美，3-噁嗪-2，4-二酮欧美精品亚洲精品日韩，產(chǎn)率達48.8％一区二区黄色无码视频，較文獻報道值高出了33％。

The asymmetric reduction of prochiral P-oxo ester, aromatic ketone and aliphatic ketone to its corresponding chiral alcohol by yeast cells were studied respectively in this work when ethyl 4-chloro-3-oxobutyrate, acetophenone and 2-octanone were as the model substrates.

本文以4-氯乙酰乙酸乙酯无码亚洲视频、苯乙酮和2-辛酮分別為β-羰基酯每日精品免费AV片在线观看、芳香酮和脂肪酮的模型底物，研究了利用活性酵母細胞催化這三類前手性酮不對稱還原合成相應(yīng)手性醇的反應(yīng)特性aa片黄色视频。