A convenient method for the bulk preparation of environmentally safe perfluoroalkyl propen-1-yl ethers via isomerization of primary allyl ethers is presented. Herein the solvent-free isomerization was carried out in the presence of two ruthenium(II) complexes: the ruthenium-hydride [RuClH(CO)(PPh3)3] and the second generation Grubb's type catalyst dichloro[1,3-bis-(2,4,6-trimethylphenyl)-4,5-dimethylimidazol-2-ylidene](thien-2-ylmethylidene)(PCy3) ruthenium(II) known as CatMETium_RF3™. A variety of reaction parameters such as the catalyst loading, the use of a base and UV photoirradiation have been investigated. We found that the presence of Bu3N is beneficial to both catalytic systems and although CatMETium_RF3™ was shown to be more active than [RuClH(CO)(PPh3)3], the catalytic activity of the latter can also be sensibly improved by UV irradiation. Carrying out the isomerization reaction with 0.1 mol% of [RuClH(CO)(PPh3)3] under UV-irradiation led to a ca. 30% improvement of the conversion compared to the same reaction carried out under sunlight and to a 60% improvement when the reaction is carried out in the dark thus mimicking the conditions present in an autoclave.
本文介绍了一种通过伯
烯丙基醚异构化批量制备环境安全型
全氟烷基
丙烯-1-基醚的简便方法。这里的无溶剂异构化是在两种
钌(II)配合物的存在下进行的:
钌酸酐[RuClH(CO)(PPh3)3]和第二代格拉布催化剂二
氯[1,3-双(2,4,6-三甲基苯基)-4,5-二甲基
咪唑-2-亚基](
噻吩-2-亚甲基)(PCy3)
钌(II),即 CatMETium_RF3™。我们对催化剂负载、碱的使用和紫外光照射等各种反应参数进行了研究。我们发现,Bu3N 的存在对两种催化体系都有好处,虽然 CatMETium_RF3™ 的活性高于 [RuClH(CO)(PPh3)3],但后者的催化活性也可以通过紫外光照射得到明显改善。在紫外线照射下使用 0.1 摩尔%的[RuClH(CO)(PPh3)3]进行异构化反应,与在阳光下进行的相同反应相比,转化率提高了约 30%,而在黑暗中进行反应时,转化率提高了 60%,从而模拟了高压釜中的条件。