Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China.
J Org Chem. 2012 Nov 2;77(21):9756-65. doi: 10.1021/jo3018507. Epub 2012 Oct 24.
A novel iridium-catalyzed asymmetric ring-opening (ARO) reaction of oxabenzonorbornadienes with a variety of phenols was reported, which afforded the corresponding trans-2-phenoxy-1,2-dihydronaphthalen-1-ol products in high yields with moderate to excellent enantioselectivities (up to 98% ee) under mild conditions. The trans products are formed via the enantioselective cleavage of a bridgehead carbon-oxygen bond in 1 followed by S(N)2 nucleophilic attack by phenols. The effects of various bisphosphine ligands, Ag (I) salts, ammonium halides, bases, and solvents on the yield and enantioselectivity of the reaction were also investigated. The trans-configuration of the product 2a was confirmed by X-ray crystal structure analysis. A possible mechanism for the present catalytic reaction was proposed.
一种新型的铱催化不对称开环（ARO）反应，报道了氧杂苯并降冰片二烯与各种酚的反应，在温和条件下以高收率和中等至优异的对映选择性（高达 98%ee）得到相应的反式-2-苯氧基-1,2-二氢萘-1-醇产物。反式产物是通过 1 中桥头碳-氧键的对映选择性断裂，然后由酚进行 S(N)2 亲核进攻形成的。还研究了各种双膦配体、Ag（I）盐、卤化铵、碱和溶剂对反应产率和对映选择性的影响。通过 X 射线晶体结构分析确定产物 2a 的反式构型。提出了一种可能的催化反应机制。
