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tinghaidub

金虫 (正式写手)

[求助] 如何屏蔽淀粉羟基

各路大侠下午好,昨日小弟有一事不明,请指教。
如下图所示:
不知如何将淀粉的2、3、6位羟基处理掉?
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celan

专家顾问 (知名作家)

从事NMR和有机化合物结构鉴定


【答案】应助回帖

tinghaidub(金币+20): 谢谢王老师悉心指导,我去找找这篇文章好好研究下。 2011-05-20 09:23:24
Microwave-accelerated methylation of starch
A novel microwave-accelerated method for methylating soluble starch is described. Soluble starch could be fully methylated in 72% yield within 4.66 min using iodomethane and 30% potassium hydroxide under microwave irradiation. The completely methylated starch thus obtained was hydrolyzed with 60% HCO2H for 1.5 min under 80% MW power, followed by 0.05 M H2SO4 for 2.0 min under 100% MW power. The partially methylated monosaccharides were separated by preparative paper chromatography and identified by their melting points and optical rotations.
原文您自己下载:
http://www.sciencedirect.com/sci ... 00&searchtype=a
8楼2011-05-20 08:53:25
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erect_lx

铁虫 (初入文坛)

【答案】应助回帖

tinghaidub(金币+1): 谢谢回帖。 2011-05-19 11:44:40
tinghaidub(金币+1): 2011-05-23 17:03:10
处理成什么啊?让-OH变成-H吗还是其他什么的
刚刚接触白乳胶方面工作
3楼2011-05-19 10:43:30
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tinghaidub

金虫 (正式写手)

引用回帖:
Originally posted by erect_lx at 2011-05-19 10:43:30:
处理成什么啊?让-OH变成-H吗还是其他什么的

不管变成什么都行,只要除去这个吸水性的东西就好。
谢谢。
梦里不知身是客
4楼2011-05-19 10:48:04
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celan

专家顾问 (知名作家)

从事NMR和有机化合物结构鉴定


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tinghaidub(金币+3): 还请解释相关步骤,谢谢。 2011-05-19 15:59:55
烷基化,比如甲基化。
5楼2011-05-19 14:50:46
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