...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Dalton transactions: An international journal of inorganic chemistry >Phenylphosphatrioxa-adamantanes: bulky,robust,electron-poor ligands that give very efficient rhodium(I) hydroformylation catalysts
【24h】

Phenylphosphatrioxa-adamantanes: bulky,robust,electron-poor ligands that give very efficient rhodium(I) hydroformylation catalysts

机译：苯基三氧杂环己烷-金刚烷：庞大，坚固，电子贫乏的配体，可提供非常有效的铑（I）加氢甲酰化催化剂

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The cage phosphines l,3,5,7-tetramethyl-6-phenyl-2,4,8-trioxa-6-phosphaadamantane (la) and l,3,5,7-tetraethyl-6-phenyl-2,4,8,trioxa-6-phosphaadamantane (1b) have been made by the acid catalysed addition of PhPH_2 to the appropriate p-diketones;the acid used (HC1,H_3PO_4 or H_2SO_4) and its concentration affect the rate and selectivity of these condensation reactions.Phosphines la and 1b react with [PdCl_2(NCPh)_2] to form complexes trans-[PdCl_2(la)_2] (2a) and trans-[PdCl_2(lb)_2] (2b) as mixtures of rac and meso diastereoisomers.The platinum(II) chemistry is more complicated and when la or 1b is added to [PtCl_2(cod)],equilibrium mixtures of trans-[PtCl_2L_2] and [Pt_2Cl_4L_2] (L = la or 1b) are formed in CH_2C1_2 solution.Meso/rac mixtures of trans-[MCl(CO)(la)_2] M = Ir (6a) or Rh (7a) are formed upon treatment of MCl_3centre dotH_2O with an excess of la and the anionic cobalt complex [NHEt_3][CoCl_3(la)] (9) was isolated from the product formed by CoCl_2 centre dot 6H_2O and la.The v_(co) values from the IR spectra of 6a and 7a suggest that la resembles a phosphonite in its bonding to Rh and Ir.Crystal structures of meso-2a,meso-2b,rac-6a and 9 are reported and in each case a small intracage C-P-C angle of ca.94~° is observed and this may partly explain the bonding characteristics of ligands la and 1b.The cone angles for la and 1b are similar and large (ca.200~°).Rhodium complexes of ligands la and 1b are hydroformylation catalysts with similarly high activity to catalysts derived from phosphites.The catalysts derived from la and 1b gave unusually low linear selectivity in the hydroformylation of hexenes.This feature has been further exploited in quaternary-selective hydroformylations of unsaturated esters;catalysts derived from la give better yields and regioselectivities than any previously reported catalyst.
机译：笼型膦1,3,5,7-四甲基-6-苯基-2,4,8-三氧杂-6-磷金刚烷（1a）和1,3,5,7-四乙基-6-苯基-2,4，通过将PhPH_2酸催化添加到适当的对二酮中来制备8，trioxa-6-磷金刚烷（1b）;所用的酸（HCl，H_3PO_4或H_2SO_4）及其浓度会影响这些缩合反应的速率和选择性。膦1a和1b与[PdCl_2（NCPh）_2]反应形成外消旋和内消旋非对映异构体混合物的反式[PdCl_2（la）_2]（2a）和反式[PdCl_2（lb）_2]（2b）。铂（II）的化学反应更加复杂，当在[PtCl_2（cod）]中添加la或1b时，在CH_2C1_2溶液中形成反式[PtCl_2L_2]和[Pt_2Cl_4L_2]（L = la或1b）的平衡混合物。反式-[MCl（CO）（la）_2] M = Ir（6a）或Rh（7a）的外消旋混合物是通过用过量的la和阴离子钴配合物[NHEt_3] [CoCl_3（la）处理过量的MCl_3中心点H_2O形成的）]（9）从由CoCl_2中心点6H_2O和la.Th形成的产物中分离出来来自6a和7a的红外光谱的e v_（co）值表明la在与Rh和Ir的键合中类似于亚膦酸酯。报道了meso-2a，meso-2b，rac-6a和9的晶体结构观察到笼内CPC角约为94〜°，这可以部分解释配体1a和1b的键合特征.1a和1b的锥角相似且较大（约200〜°）。 1a和1b是与亚磷酸酯衍生的催化剂具有相似活性的加氢甲酰化催化剂.1a和1b衍生的催化剂在己烯的加氢甲酰化反应中具有极低的线性选择性，这一特征已在不饱和酯的季选择性加氢甲酰化反应中得到了进一步的利用。与先前报道的任何催化剂相比，由Ia衍生的苯可提供更好的收率和区域选择性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号