Transition metal-catalyzed dehydrogenation is a clean oxidation method requiring no additional oxidants. We have accomplished a heterogeneous Pd/C-catalyzed aqueous dehydrogenation of 1,4-cyclohexadienes and cyclohexenes to give the corresponding highly-functionalized arenes. Furthermore, various arenes could be efficiently constructed in a one-pot manner via a Diels–Alder reaction and the following
selective synthesis of 1‐substituted (E)‐buta‐1,3‐dienes via palladium‐catalyzed Suzuki–Miyaura cross‐coupling of (E)‐alkenyl iodides with 4,4,5,5‐tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane (1) is reported. The vinylboronate pinacol ester (1) acts as a vinyl building block to show high chemoselectivity for the Suzuki–Miyaura pathway versus Heck coupling in the presence of biphasic conditions (Pd(PPh3)4, aqueous
Selective 1,2‐Aminoisothiocyanation of 1,3‐Dienes Under Visible‐Light Photoredox Catalysis
作者:Weisi Guo、Qian Wang、Jieping Zhu
DOI:10.1002/anie.202014518
日期:2021.2.19
N‐aminopyridinium salts and TMSNCS affords 1,2‐aminoisothiocyanation products in a highly chemo‐ and regio‐selective manner under mild photoredox catalytic conditions. Mechanistic studies indicate that the facile isomerization of allyl thiocyanates to allyl isothiocyanates under photocatalytic conditions is responsible for the selective formation of the observed products. The mild isomerization protocol