Transfer Hydrocyanation of α- and α,β-Substituted Styrenes Catalyzed by Boron Lewis Acids
作者:Patrizio Orecchia、Weiming Yuan、Martin Oestreich
DOI:10.1002/anie.201813853
日期:2019.3.11
A straightforward gram‐scale preparation of cyclohexa‐1,4‐diene‐based hydrogen cyanide (HCN) surrogates is reported. These are bench‐stable but formally release HCN and rearomatize when treated with Lewis acids. For BCl3, the formation of the isocyanide adduct [(CN)BCl3]− and the corresponding Wheland complex was verified by mass spectrometry. In the presence of 1,1‐di‐ and trisubstituted alkenes,
据报道,一种简单的克级制备基于环六-1,4-二烯的氰化氢(HCN)替代物。它们稳定,但用路易斯酸处理后会正式释放HCN并重新致瘤。对于BCl 3,通过质谱法验证了异氰酸酯加合物[(CN)BCl 3 ] -和相应的Wheland配合物的形成。在1,1,1-二和三取代的烯烃的存在下,HCN从替代物转移到C-C双键,从而产生具有马尔可夫尼科夫选择性的高度取代的腈。转移氢氰化的成功取决于所使用的路易斯酸;催化量的BCl 3和(C 6 F 5)2已证明BCl有效,而B(C 6 F 5)3和BF 3 OEt 2无效。