Thapa Surendra, Dhungana Roshan K, Magar Rajani Thapa, Shrestha Bijay, Kc Shekhar, Giri Ramesh
Department of Chemistry & Chemical Biology , The University of New Mexico , Albuquerque , NM 87131 , USA . Email:
Chem Sci. 2017 Nov 27;9(4):904-909. doi: 10.1039/c7sc04351a. eCollection 2018 Jan 28.
We report a Ni-catalysed diarylation of unactivated olefins in dimethylpyridylvinylsilane by intercepting Heck C(sp)-NiX intermediates, derived from aryl halides, with arylzinc reagents. This approach utilizes a modifiable pyridylsilyl moiety as a coordinating group that plays a dual role of intercepting oxidative addition species to promote Heck carbometallation, and stabilizing the Heck C(sp)-NiX intermediates as transient metallacycles to suppress β-hydride elimination, and facilitate transmetalation/reductive elimination. This method affords 1,2-diarylethylsilanes, which can be readily oxidized to 1,2-diarylethanols that occur as structural motifs in 3-aryl-3,4-dihydroisocoumarin and dihydrostilbenoid natural products.
我们报道了一种镍催化的未活化烯烃在二甲基吡啶基乙烯基硅烷中的双芳基化反应，该反应通过用芳基锌试剂截获由芳基卤化物衍生的Heck C(sp)-NiX中间体来实现。这种方法利用可修饰的吡啶基硅基部分作为配位基团，该基团具有双重作用：截获氧化加成物种以促进Heck碳金属化，以及稳定Heck C(sp)-NiX中间体作为瞬态金属环以抑制β-氢化物消除，并促进转金属化/还原消除。该方法可得到1,2-二芳基乙基硅烷，其可容易地氧化为1,2-二芳基乙醇，这些化合物在3-芳基-3,4-二氢异香豆素和二氢茋类天然产物中作为结构基序出现。
