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5-羟甲基尿嘧啶的合成如何提高产率,希望得到帮助

请问5-羟甲基尿嘧啶的实验室合成需要注意哪些,我目前用的方法是用多聚甲醛、尿嘧啶、KOH水溶液搅拌加热来合成,但是产率不高,我还没有做纯化,产率最高就22%,希望得到前辈的指导,如何提高产率。 显示全部
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,研发部主管 14天前回答
Example 1a 5-(Hydroxymethyl)-1,3-dihydropyrimidine-2,4-dione A 2-L, three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and nitrogen-inlet bubbler was charged with uracil (185.0 g, 1650 mmol) (Aldrich), paraformaldehyde (61.50 g, 2050 mmol as formaldehyde) (Aldrich), and a solution of potassium hydroxide (86.9%, 59.95 g, 928.5 mmol) (Aldrich) in water (1.445 L). The mixture was stirred at 50-52° C. for 68 h. TLC analysis indicated complete reaction. After concentration at 60° C./14 mmHg to a volume of ca. 500 mL, the residue was diluted with acetone (500 mL). The resulting precipitate was collected by filtration, washed with acetone, and dried by suction, then at 50° C./25 mmHg to give crude 5-(hydroxymethyl)-1,3-dihydropyrimidine-2,4-dione (250 g) as a white solid. The combined mother liquor and washes were concentrated to a volume of ca. 100 mL and a solution of hydroxylamine hydrochloride (27.52 g, 396.0 mmol, Aldrich) in water (100 mL) was added. The resulting precipitate was collected by filtration, washed with acetone, and dried by suction to give second crop of crude 5-(hydroxymethyl)-1,3-dihydropyrimidine-2,4-dione (34 g) as a white solid. The two lots were combined (244 g, 4% overweight) and used directly in the next step.
Chen, Yi; Daniewski, Andrzej Robert; Harris, William; Kabat, Marek Michal; Liu, Emily Aijun; Liu, Jin-Jun; Luk, Kin-Chun; Michoud, Christophe
US2004/38995, 2004, A1
看了一下操作,比较好操作,有可能影响收率的点:
1. 反应终点的检测是否准确
2. 多聚甲醛用的是无水的还是含水的
3. 水是否完全旋干,产品可能会溶水
 
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相关化合物
5-羟甲基尿嘧啶
CAS: 4433-40-3
供应商:41
分子式:C5H6N2O3
密度 1.401g/cm3
熔点 >300°C(lit.)
沸点 530.4ºC at 760mmHg
闪光点 274.6ºC
折射率 1.528
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5-甲基尿嘧啶价格
  • 安徽立创生物科技有限公司
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  • 所在地: 安徽铜陵市
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4433-40-3 | 5-羟甲基尿嘧啶
  • 武汉欣欣佳丽生物科技有限公司
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  • 所在地: 湖北武汉
  • 电话: 15527693592
5-羟甲基脲嘧啶
  • 湖北万得化工有限公司
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  • 所在地: 湖北天门市
  • 电话: 15827180502 座机:027-59210159
5-羟甲基脲嘧啶(4433-40-3)
  • 湖北齐飞医药化工有限公司
  • 店铺产品详情
  • 所在地: 湖北天门市
  • 电话: 18871456855 座机: 027-59322506
5-羟甲基脲嘧啶
  • 湖北津乐达化工有限公司
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  • 所在地: 湖北武汉市
  • 电话: 027-62300166
 
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