| 查看: 217 | 回复: 2 | |||
| 当前主题已经存档。 | |||
| 【悬赏金币】回答本帖问题，作者rocket18将赠送您 5 个金币 | |||
[求助]
帮忙翻一下摘要。。。
|
|||
|
Continuous stable enantioselective hydrogenation of alkyl pyruvate esters using pre-modified cinchonidine platinum catalysts Robert L. Jenkins, Paul McMorn, and Graham J. Hutchings* Department of Chemistry, Cardiff University, P. O. Box 912Cardiff, CF10 3TB UK Received 15 July 2004; accepted 5 December 2004 Pre-modification of a 5 wt% Pt/c-Al2O3 catalyst with cinchonidine (0.1 g g)1 catalyst) leads to a catalyst that give stable enantioselection when using a trickle-bed flow reactor at ambient temperature and pressure. With dichloromethane as solvent sustained enantiomeric excess of >70% for the hydrogenation of ethyl pyruvate to (R)-ethyl lactate is observed and this is maintained with very low cinchonidine/catalyst ratios. With dichloromethane the conversion decreases with time an effect we consider to be due to the formation of small amounts of polymer on the catalyst surface. When ethanol is used as solvent the yield of (R)-ethyl lactate is stable throughout the test period, although the enantiomeric excess was much lower at ca. 35%. KEY WORDS: enantioselective hydrogenation; ethyl pyruvate hydrogenation; butadione hydrogenation; Pt/c-Al2O3 catalysts. |
回复此楼» 猜你喜欢
327求调剂
已经有11人回复
-
08工科求调剂290分
已经有11人回复
-
一志愿985初试354分生物调剂
已经有3人回复
-
一志愿2110，化学学硕310分，本科重点双非求调剂
已经有13人回复
-
353求调剂
已经有8人回复
-
308求调剂
已经有16人回复
-
334求调剂
已经有14人回复
-
一志愿0807 数一英一 313 有没有二轮调剂
已经有7人回复
-
复试调剂，一志愿郑州大学材料与化工289分
已经有14人回复
-
086000调剂
已经有3人回复
2楼2008-04-19 09:42:27
3楼2008-04-19 13:36:59
