Air- and Water-Tolerant Rare Earth Guanidinium BINOLate Complexes as Practical Precatalysts in Multifunctional Asymmetric Catalysis
作者:Jerome R. Robinson、Xinyuan Fan、Jagjit Yadav、Patrick J. Carroll、Alfred J. Wooten、Miquel A. Pericàs、Eric J. Schelter、Patrick J. Walsh
DOI:10.1021/ja502568g
日期:2014.6.4
1'-bi-2-naphtholate; RE/M/B = 1/3/3) are among the most enantioselective asymmetric catalysts across a broad range of mechanistically diverse reactions. However, their widespread use has been hampered by the challenges associated with their synthesis and manipulation. We report here the self-assembly of novel hydrogen-bonded rare earth metal BINOLate complexes that serve as bench-stable precatalysts for
Shibasaki 的 REMB 催化剂(REMB;RE = Sc、Y、La-Lu;M = Li、Na、K;B = 1,1'-bi-2-naphtholate;RE/M/B = 1/3/3)在广泛的机械多样化反应中,是最具对映选择性的不对称催化剂之一。然而,它们的广泛使用受到与其合成和操作相关的挑战的阻碍。我们在此报告了新型氢键稀土金属 BINOLate 配合物的自组装,这些配合物可作为 Shibasaki 的 REMB 催化剂的工作台稳定预催化剂。氢键胍阳离子在二级配位球中的结合导致了独特的性质,最显着的是,提高了对溶液中和固态中水分的稳定性。我们利用这些特性开发了直接、高产、和可扩展的露天合成,可以从廉价的水合稀土起始材料中快速获得结晶的、不吸湿的复合物。这些化合物可用作 Shibasaki 的 REMB 框架的预催化剂,我们已经证明我们的系统在几个机械不同的反应(包括迈克尔加成、氮杂