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6金币求助一实验操作的翻译,谢谢!
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Synthesis of 14b. A mechanically stirred solution of 14(125 g, 0.752 mol) in 500mL of pyridine was cooled to -10℃ in an ice-salt bath under nitrogen. p-Toluenesulfonyl chloride (175 g, 0.918 mol) was added in one portion under the inert atmosphere via Gooch tubing. The temperature rose to 40 "C during 15-20 min, but returned to 5"C where it was maintained for 2 h. Twenty 1-mL portions of water were next introduced at such a rate that the temperature did not exceed 5℃. The reaction mixture was poured into ether (1 L) and extracted with ice-cold 5 M sulfuric acid until the aqueous layer remained acidic. The ethereal phase was washed with two 200-mL portions each of water and 5% sodium bicarbonate(碳酸氢钠) solution prior to drying and solvent evaporation. The residual material was dissolved in hexane and filtered through a pad of Celite(硅藻土) to remove a black-colored impurity. Finally, 14b was recrystallized six times from 500 mL of hexane aliquots（等分试样） to give 173 g (72%) of colorless crystals, mp 51.0-51.8 "C (lit.24p26 mp 49-50 "C); [a]25D-2 5.6" (c 1.0, C2H50H). Synthesis of 15 . A mechanically stirred, nitrogenblanketed solution of 14b (200 g, 0.624 mol) in dimethyl sulfoxide (1 L, freshly distilled from calcium hydride) was cooled briefly in a cold water bath and treated in one portion with freshly sublimed（升华\纯化）potassium tert-butoxide (69.0 g, 0.615 mol). The base serves as limiting reagent to offset isomerization of product diene. The temperature rose to approximately 45 "C and a brown color developed. As reaction proceeded, the color dissipated to a light yellow hue（色彩）. After the initial exotherm（放热的） subsided(退落), the mixture was heated at 75 "C for 10 h, cooled to room temperature, and diluted with 800 mL of hexane. The lower layer, mostly dimethyl sulfoxide, was diluted(稀释) with 1 L of water and extracted with two 100-mL portions of hexane. The combined hexane layers were washed with water (5 X 200 mL), dried over magnesium sulfate(硫酸镁), and rotary evaporated at 40 Torr and 25 "C to leave a yellow oil. Distillation through a 5-in. Vigreux column gave 74.0 g (80%) of nopadiene as a clear colorless oil, bp 78-79 "C/25 Torr; [a]24D+3 .8" (c8.4, hexane). |
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mnbbnm123
铁杆木虫 (正式写手)
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我给你译一篇
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人善天不欺(金币+2,VIP+0):谢谢！
人善天不欺(金币+2,VIP+0):谢谢！
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合成14b，在机械搅拌下，14化合物（125克，0.752mol）溶解在500ml吡啶中，在氮气保护下，用冰盐浴冷却到-10度，一次性加入对甲苯磺磺酰氯（175克，0.918mol），温度在15-20分钟升到40度，待温度降到5度后，保持2小时。20份1ml水，加入反应液中，保持反应液温度不高于5度，反应混合物倒入1L乙醚中，用冰冷的5M硫酸萃取，直到水层保持酸性，轻组分中200m L水洗一次，5%碳酸氢钠洗一次。干燥并蒸发发溶剂，残余物溶于己烷通过一个硅藻土垫，过滤，除去黑色不纯物，最后14b在己烷（500ml，等分试样）重结晶6次，得到173克无色结晶，熔点：51.0-51.8度，收率72%。 备注：你的14没有给出结构。 |
2楼2009-01-02 08:52:15
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人善天不欺(金币+4,VIP+0):呵呵，谢谢！
人善天不欺(金币+4,VIP+0):呵呵，谢谢！
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合成14 b 14(125 g, 0.752 mol)溶于500ml的吡啶，机械搅拌，氮气保护下用冰盐浴冷却至-10℃。通过Gooch管通入惰性气体后，加入对苯磺酰氯(175 g, 0.918 mol)。在15-20分钟之间反应液的温度升高至40 "C，而后回落至5"C，并在该温度保持两小时。加入21ml的水，加入的速度应以保持温度不超过5℃为宜。将反应液倾入1L的乙醚中，5M且冰浴冷却的硫酸萃取直至水层呈现酸性。乙醚层用200ml的水与碳酸氢钠各洗涤一次，干燥，旋干。残余物溶于己烷，硅藻土过滤除去黑色杂质。最后，14b用500ml的己烷等分试样6次重结晶得到173g(72%)白色晶体，mp 51.0-51.8 "C [a]25D-2 5.6" (c 1.0, C2H50H)。 合成15 14b (200 g, 0.624 mol)的二氯亚砜溶液（1l，氢化钙新鲜蒸馏）简单地用冷水浴冷却，加入新鲜升华的叔胡椒基丁醚化钾(69.0 g, 0.615 mol)。加碱（叔胡椒基丁醚化钾）是作为限速剂以防止产物二烯的同分异构化。加碱后温度上升至45 "C，并慢慢变成褐色。.随着反应的进行，颜色褪去呈淡黄色。反应刚开始的放热停止后，将反应液加热至75 "C，加热十小时，然后冷却至室温，用800ml的己烷稀释。下层，大多数是二氯亚砜，用1L的水稀释，用100ml的己烷萃取两次。 合并己烷层，水洗5 X 200 mL，无水硫酸镁干燥，室温旋干得到黄色的油状物。Distillation through a 5-in. Vigreux column gave 74.0 g (80%) of nopadiene as a clear colorless oil, bp 78-79 "C/25 Torr; [a]24D+3 .8" (c8.4, hexane). 这句话好像有语法错误，特别是5-in.不是很明白。 |
3楼2009-01-02 21:14:39