Based on the absorption property of glyoxime which can be formed by addition reaction of aldehyde group and hydroxylamine in the UV-spectral region,spectrophotometric determination of glyoxal in glyoxal solution was proposed.

利用醛基與羥胺在酸性條件下的成肟反應產(chǎn)物乙二醛二肟對紫外光的吸收特性亚洲色图在线综合，用紫外分光光度法測定乙二醛的含量男人天堂美女抽查插。

Firstly, 3-ethylthiobutanal was prepared from crotonaldehyde reacting with ethanehiol in triethylamine with high yield. Secondly, methyl acetoacetate was converted to 6-ethylthiohept-3-en-2-one by three steps via hydrolysis, condensation with 3-ethyltio-butanal and dehydration, then 6-ethylthiohept-3-en-2-one was cycloco ndensed with dimethyl malonate by Michael addition and Claisen condensation, followed by saponification and decarboxylation to give the intermediate of 5-(2-ethylthiopropyl)-cyclohexane-1,3-dione.

首先免费的黄色视频91，以巴豆醛與乙硫醇為原料直接在线免费看黄网站，在三乙胺的催化作用下高收率制得3-乙硫基丁醛；然后從乙酰乙酸甲酯出發(fā)人人插人人做，通過堿水解爱爱免费网站欧美、與3-乙硫基丁醛縮合、脫水三步反應合成6-乙硫基-3-烯-2-庚酮日韩侵犯精品视频在线，接著6-乙硫基-3-烯-2-庚酮與丙二酸二甲酯通過Michael加成和Claisen縮合成環(huán)日本免费一级高清婬片日本，再通過皂化和脫羧反應生成中間體5-[2-丙基]-1，3-環(huán)己二酮超碰a；再與丙酸酐反應丙跻磺粕笃化，最后與0-3-氯-2-丙烯基羥胺肟化欧美一区欧美一区，得到目標化合物烯草酮日韩孕妇自拍视频直播在线观看网站。