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wxd54810770木虫 (初入文坛)
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合成方面翻译求助，谢谢！
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THIATION WITH 2,4-BIS(4-METHOXYPHENYL)-1,3,2,4- DITHIADIPHOSPHETANE 2,4-DISULFIDE: N-METHYLTHIOPYRROLIDONE [2-Pyrrolidinethione, 1-methyl-] Submitted by I. Thomsen, K. Clausen, S. Scheibye, and S.-O. Lawesson1. Checked by Clayton H. Heathcock, Mark Sanner, and Terry Rosen. 1. Procedure Caution! Preparation of 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide must be carried out in an efficient hood because hydrogen sulfide is evolved. Also, benzene has been identified as a carcinogen; OSHA has issued emergency standards on its use. All procedures involving benzene should be carried out in a well-ventilated hood, and glove protection is required. A. 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (1). A dry 1-L, three-necked, round-bottomed flask, fitted with a reflux condenser, mechanical stirrer, and ground-glass stopper, is charged with 111.0 g (0.25 mol) of phosphorus sulfide, P4S10 (Note 1) and 270 g (2.5 mol) of anisole (Note 1). Stirring is commenced and the mixture is heated at reflux temperature by use of a heating mantle. After 1 hr, the solution is homogeneous and after a second hour 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (1) begins to precipitate. The reaction mixture is allowed to cool to room temperature and the precipitate is filtered (Note 2) and washed with anhydrous ether (2 × 50 mL) and 50 mL of anhydrous chloroform (free of alcohols) to yield 160–165 g (79–82%) of pale-yellow crystals, mp 228°C (Note 3) and (Note 4). B. N-Methylthiopyrrolidone (2). A 200-mL, three-necked, round-bottomed flask is fitted with a rubber septum, thermometer, magnetic stirring bar, and reflux condenser equipped with a nitrogen bubbler. The flask is charged with 19.8 g (19.3 mL, 0.20 mol) of N-methylpyrrolidone (Note 5) and 40.4 g (0.10 mol) of 1, whereupon the temperature of the reaction mixture increases to 75–80°C. After 5 min, 35 mL of benzene (Note 6) is added by syringe and the mixture is stirred while being brought to reflux (Note 7). The mixture is heated at reflux for 2 hr (Note 8) and then cooled to room temperature, whereupon it again becomes heterogeneous. The benzene is removed with the aid of a rotary evaporator and the resulting yellow slurry is distilled under reduced pressure through a 5-cm Vigreux column to provide 23.0 g (100%) of N-methylthiopyrrolidone (2) as a yellow liquid, bp 94–97°C/0.03 mm (Note 9). 2. Notes 1. Commercial phosphorus sulfide, P4S10, is used without purification. Checkers used P4S10 from Matheson, Coleman and Bell and from Alfa Products, Morton Thiokol, Inc. Best results (yield, melting point) were obtained with the Alfa sample, mp 291–295°C. 2. Excess anisole (137 g) can be recovered by distillation of the filtrate. 3. The product is somewhat hygroscopic and should be stored in an airtight container. It is also available as Lawesson's reagent from Aldrich, Fluka, and from Merck–Schuchard. 4. The checkers obtained 176 g (87%) of 1, mp 228–231°C. 5. Commercial material from the Aldrich Chemical Company was stored over Linde 4A molecular sieves. 6. Benzene was distilled from and stored over sodium wire. 7. During this operation most of the yellow solid gradually dissolves, affording a clear yellow solution with small amounts of suspended solid. When reflux begins, the internal temperature of the reaction mixture is 95°C. 8. The reaction time can be decreased to 3 min by the use of toluene as solvent. 9. The purified product freezes when stored in a refrigerator. The spectral properties are as follows: 1H NMR (CDCl3) δ: 2.07 (quintet, 2 H, J = 7), 3.03 (t, 2 H, J = 7), 3.29 (s, 3 H), 3.77 (t, 2 H, J = 7). IR (neat): 1520 cm−1. 3. Discussion A variety of thiating reagents are known: H2S,2 H2S/HCl,3 H2S2/HCl,4 (Et2Al)2S,5 (EtAlS)n,6 SiS2,7 B2S3,7 PCl5/Al2S3/Na2SO4,8 Na2S/H2SO4,9 P2S510 P2S5/Pyridine,11 P2S5/NEt3,12 P2S5/NaHCO3,13 RPS (OR1)214 PSClx (NMe2)3–x (X = 0–3),15 and SCNCOOEt.16 The reagent described here, 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (1),17 offers a number of advantages as a thiating reagent. It is easily prepared in a simple one-step procedure employing commercially available starting materials. It has a satisfactory shelf life, provided it is protected from moisture. In contrast to commercial P4S10, compound 1 is a well-defined reagent that gives reproducible results, usually in high yield. Under defined conditions, certain selectivity has been observed.18,19,20 Other methods for the preparation of analogs of 1 have been described.21,22,23 The thiation procedure described here24 is an example of a general synthetic method for the conversion of carbonyl to thiocarbonyl groups. Similar transformations have been carried out with ketones,25 carboxamides,26,27,28,29,30 esters,31,32 thioesters,31 lactones,18,33 thiolactones,18 imides,24 enaminones,34 and protected peptides.35 |
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slowstar
木虫 (职业作家)
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10楼2009-10-16 10:43:49
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汤姆森提出的一，光克劳森，第Scheibye和S.-O. Lawesson1。 克莱顿检查每小时Heathcock，马克塞纳和特里罗森。 1。程序 注意！制备2,4 -二（4 -甲氧基苯基）-1,3,2,4 - dithiadiphosphetane 2,4 -二硫必须进行有效的引擎盖，因为硫化氢是进化的。此外，苯已被确定为一种致癌物质，一氧化碳已发出紧急其使用的标准。有关苯的所有程序应进行在通风良好的排油烟机，手套的保护是必需的。 答：2,4 -二（4 -甲氧基苯基）-1,3,2,4 - dithiadiphosphetane 2,4 -二硫（1）。阿干1 - L的三颈，圆平底瓶，与回流冷凝器安装，机械搅拌器，地面玻璃挡，被控一百十一点零克（0.25 -1）硫化磷，P4S10（注1）及270克（2.5 -1对苯甲醚）（注1）。搅拌是展开的混合物加热的加热回流温度下使用地幔。 1小时后，该解决方案是均匀，第二个小时后，2,4 -二（4 -甲氧基苯基）-1,3,2,4 - dithiadiphosphetane 2,4 -二硫（1）开始沉淀。反应混合物让其冷却到室温和沉淀过滤（注2）和无水乙醚洗涤（2 × 50毫升）和50毫升的无水氯仿（无醇），收益率为160-165克（79 - 82％）的浅黄色结晶，熔点228 ° C（注3）和（注4）。 二ñ - Methylthiopyrrolidone（2）。一个200毫升，三颈，圆平底瓶配有橡胶隔膜，温度计，电磁搅拌栏和回流冷凝器的氮喷水式饮水设备。该瓶被指控19.8克（19.3毫升，0.20摩尔）的N -甲基吡咯烷酮（注5）和40.4克（0.10 -1）1，于是在反应混合物的温度升高到75-80摄氏度5分钟后，35毫升苯（注6）是由注射器添加并搅拌混合物，是在被带到返流（注7）。该混合物被加热回流2小时（注8），然后冷却至室温，在那里再次成为异类。苯是被遣送离境的援助和旋转蒸发器产生的黄泥浆，是通过蒸馏5厘米维格勒列减压下提供二十三点○克（100％）的N - methylthiopyrrolidone（2）为黄色液体，沸点94 -97 ° C/0.03毫米（注9）。 2。注释 1。商业硫化磷，P4S10，使用时不净化。跳棋使用的洋行，科尔曼和贝尔和阿尔法产品，P4S10莫顿聚硫橡胶公司的最佳结果（收益率，熔点）对香港阿尔法样本，熔点291-295 ° C的获得 2。过量苯甲醚（137七）可以恢复由滤液蒸馏。 3。该产品是有点吸湿，应该在一个密闭容器中。它也可以作为劳森试剂的秩序，铵，以及默克制药，Schuchard。 4。在棋子获得176克（87％）1，熔点228-231 ° C的 5。从秩序化学公司的商业资料被储存在林德4A分子筛。 6。苯是提炼出来，并储存在钢丝 7。在这次行动中的黄色固体逐渐溶解，能够给予明确的悬浮固体与少量黄色的解决方法。当反流开始时，反应混合物的内部温度为95℃， 8。反应时间可减少到3分钟由甲苯为溶剂的使用。 9。纯化的产品时，冻结在冰箱中。的光谱性质如下：核磁共振（氯仿）δ：2.07（五重奏，2第H，J = 7），3.03（吨，2第H，J = 7），3.29（秒，3小时），3.77（吨， 2第H，J = 7）。红外（整洁）：1520 cm - 1的。 3。讨论 thiating试剂的各种已知：硫化氢，2 H2S/HCl，3 H2S2/HCl，4（Et2Al）2秒，5（EtAlS）不详，6 SiS2，7 B2S3，7 PCl5/Al2S3/Na2SO4，8 Na2S/H2SO4， 9 P2S510 P2S5/Pyridine，11 P2S5/NEt3，12 P2S5/NaHCO3，13退休保障计划（OR1）214 PSClx（NMe2）3 ×（X = 0-3），15及SCNCOOEt.16这里描述的试剂，2,4双（4 -甲氧基苯基）-1,3,2,4 - dithiadiphosphetane 2,4 -二硫（1），17提供了条件作为thiating试剂号码。它很容易编写一个简单的单步过程采用商业化起始原料。它有一个令人满意的保质期，只要是有防潮保护。相对于商业P4S10，化合物1是一个定义良好的试剂是使重复的结果，通常在高产。在特定条件下，一些选择性已observed.18，19,20为1类似物的制备方法已经被其他described.21，22,23 该thiation过程中所述here24是一个普遍适用的羰基转化为硫羰基合成法群体的例子。类似的变革已经进行了酮，25酰胺，26,27,28,29,30酯，31,32硫酯，内酯31，18,33 thiolactones，18酰亚胺，24 enaminones，34和保护peptides.35 |
2楼2009-10-15 20:07:38
slowstar
木虫 (职业作家)
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3楼2009-10-15 21:50:16
slowstar
木虫 (职业作家)
- 翻译EPI: 13
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wxd54810770(金币+10,VIP+0): 10-16 16:39
wxd54810770(金币+10,VIP+0): 10-16 16:39
| A. 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide (1)的合成。所需仪器：1L的三口圆底烧瓶，回流冷凝管，机械搅拌器，磨口玻璃塞。将111.0g(0.25mol)硫化磷P4S10（注意事项1）和270g(2.5mol) 苯甲醚（注意事项1）加入三口圆底烧瓶里，机械搅拌，用加热套加热使之回流。1h（小时）后，得均相溶液（澄清液），再过1h，化合物(1)开始沉淀析出。（至于要沉淀多久才完全，你自己实验时点板观察）反应物冷至室温，抽滤（注意事项2），用无水乙醚（2× 50 mL) and 50 mL无水氯仿CHCl3（无杂质醇）洗涤，可得到160–165 g (产率79–82%)浅黄色晶体，熔点228°C (Note 3) and (Note 4)。 |
4楼2009-10-15 22:21:12