Scope and Mechanism of the Ruthenium-Catalyzed Dehydrative C–H Coupling of Phenols with α,β-Unsaturated Carbonyl Compounds: Expedient Synthesis of Chromene and Benzoxacyclic Derivatives
作者:Bhanudas Dattatray Mokar、Chae S. Yi
DOI:10.1021/acs.organomet.9b00629
日期:2019.12.23
4-disubstituted chromene derivatives, whereas the analogous coupling with cyclic enones yielded 9-hydroxybenzoxazole products. The reaction of 3,5-dimethoxyphenol with PhCH═CHCDO resulted in the chromene product with a significant H/D exchange to both benzylic and vinyl positions. The most significant carbon isotope effect from the coupling of 3,5-dimethoxyphenol with 4-methoxycinnamaldehyde was observed
ne烯和苯并氧杂环衍生物是通过苯酚与α,β-不饱和羰基化合物的钌催化脱水CH-H偶联反应有效合成的。发现阳离子钌氢化物络合物是有效的催化剂,可用于苯酚与烯类的偶联和环化,形成苯并二氢萘产品。苯酚与线性烯酮的偶合得到2,4-二取代的色烯衍生物,而与环烯酮的类似偶合产生9-羟基苯并恶唑产物。3,5-二甲氧基苯酚与PhCH = CHCDO的反应生成的苯并二氢萘产物在苯甲基和乙烯基位置均具有显着的H / D交换。3的偶合最显着的碳同位素效应 在色烯产物的α-烯烃碳上观察到5-二甲氧基苯酚与4-甲氧基肉桂醛(C(2)= 1.067)。3,5-二甲氧基苯酚与对位取代的p -XC 6 H 4 CH = CHCHO表现出线性相关性,并具有吸电子基团(ρ= +1.5; X = OCH 3,CH 3,H,F,Cl)的强促进作用。通过催化偶合法合成了几种具有生物活性的色酮衍生物。该催化方法提供了一种方便的合成方