Disclosed herein is an efficient synthetic route for the synthesis of functionalized 2-benzyl benzo[b]furans via a regioselective 5-exo-trig intramolecular oxidative cyclization of ortho-cinnamyl phenols using [PdCl2(CH3CN)2] as catalyst and benzoquinone as an oxidant. Further, a sequential ortho-cinnamylation of phenols using cinnamyl alcohols catalyzed by Re2O7, followed by an oxidative cyclization
本文所公开的是用于官能化的2-苄基苯并[合成的有效合成路线b ]呋喃经由区域选择性5 -外-TRIG分子内的氧化环化邻-使用肉桂酚[的PdCl 2(CH 3 CN)2 ]作为催化剂和苯醌作为氧化剂。此外,使用由Re 2 O 7催化的肉桂醇对苯酚进行邻位邻肉桂酸化,然后使用上述Pd催化剂进行氧化环化。反应显示出广泛的底物范围,具有良好至优异的产率。
Molybdenum(II)-Catalyzed Allylation of Electron-Rich Aromatics and Heteroaromatics
作者:Andrei V. Malkov、Stuart L. Davis、Ian R. Baxendale、William L. Mitchell、Pavel Kočovský
DOI:10.1021/jo982178y
日期:1999.4.1
The stable, readily available molybdenum(II) complexes [Mo(CO)(4)Br-2](2) (B) and Mo(CO)(3)(MeCN)(2)(SnCl3)Cl (C) have been found to catalyze C-C bond-forming allylic substitution with electron-rich aromatics (e.g., 15 + PhOMe --> 62) and heteroaromatics (e.g., 15 + 36 --> 88) as nucleophiles under mild conditions (room temperature, 30 min-3 h). Remarkable is the para-selectivity for anisole, whereas phenol tends to favor ortho-substitution in certain instances. Mechanistic and stereochemical experiments are indicative of Lewis-acid catalysis rather than a metal template-controlled process.