Mixed Phosphane η<sup>5</sup>-CpRuCl(PR<sub>3</sub>)<sub>2</sub>Complexes as Ambifunctional Catalysts for Anti-Markovnikov Hydration of Terminal Alkynes
at C-6) for anti-Markovnikovhydration of terminal alkynes to aldehydes is retained when one heterocyclic ligand L is replaced by L' = PPh(3). Equal amounts of CpRuCl(PPh(3))(2) (1) and phosphane L in acetone solution equilibrate to a mixture of 1, CpRuCl(L)(PPh(3)) (2), and CpRuCl(L)(2) (3), which acts as highly active in situ catalyst for preparative anti-Markovnikovhydration of alkynes in water-rich
[CpRu(L)(2)(MeCN)]PF(6)(L = 2-diphenylphosphinopyridine 在 C-6 处具有庞大的基团)在一个杂环配体时保留了对末端炔烃的反马尔科夫尼科夫水合反应的催化活性L 由 L' = PPh(3) 代替。丙酮溶液中等量的 CpRuCl(PPh(3))(2) (1) 和磷烷 L 平衡为 1、CpRuCl(L)(PPh(3)) (2) 和 CpRuCl(L)(2) 的混合物) (3),在富水介质(2 mol % [Ru],60 °C,3-18 h in 4:1 (v/v ) 丙酮/水)。反应在 160 °C 下 <15 分钟内完成。
A facile lipase-catalyzed KR approach toward enantiomerically enriched homopropargyl alcohols
作者:Paweł Borowiecki、Maciej Dranka
DOI:10.1016/j.bioorg.2019.01.050
日期:2019.12
(E ≫ 500) furnishing both resolution products of the racemic 1-phenylbut-3-yn-1-ol in highly enantiomerically enriched form (up > 99% ee). Variable reaction parameters, such as the acyl-group donor reagent as well as solvent, were additionally screened to establish their impact on the stereochemical outcome. For optimal biocatalytic systems established with model substrate, the enzymatic transformations were
of oligo-1,4-diol building blocks has been realized via (a) propargylation of an aldehyde with allenylzinc bromide, (b) alcohol protection and (c) ruthenium-catalyzed anti-Markovnikov hydration of the terminal alkyne to release an aldehyde for the next iteration. Linear chains with 1,4-, 1,4,7- 1,4,7,10- and 1,4,7,10,13- functionalization patterns have been obtained by consecutive sequential iterations