Diversification of the 3-benzazepine scaffold applying Ugi/reductive Heck sequence

Ugi Reaction Followed by Intramolecular Diels–Alder Reaction and Elimination of HCl: One‐Pot Approach to Arene‐Fused Isoindolinones

“…Post-Ugi processes involving triple-bond carbopalladation have been extensively used to prepare indol-2-ones, [10] blue-emissive isoquinolines, [11] and 3-benzazepines. [12] In 2002, Wright and co-workers described a reaction sequence leading to isoindolinones 5 that involved an Ugi reaction followed by a Yb(OTf ) 3 -catalysed intramolecular Diels-Alder reaction of furan (IMDAF) and a subsequent oxo bridgeopening isomerization (Scheme 1a). [13] In that process, propiolic acid 2 and furfural (1) were used as dienophile and diene source, respectively.…”

“…Using propiolic acid derived Ugi adducts bearing an additional nucleophilic reactive centre, a wide range of medium‐ring‐containing heterocycles and structurally unique polycyclic frameworks have been assembled through activation of the triple bond towards nucleophilic attack using coinage‐metal catalysts or strong Brønsted acids. Post‐Ugi processes involving triple‐bond carbopalladation have been extensively used to prepare indol‐2‐ones, blue‐emissive isoquinolines, and 3‐benzazepines …”

“…(q, J = 32.2 Hz), 128.3, 125.6, 124.4 (q, J = 272.3 Hz), 123.4 (q, J = 3.0 Hz), 123.0 (q, J = 4.6 Hz), 119.8, 64.4, 51.8, 46.8, 28.5,12.2 ppm. IR (ATR): ν =…”

Heck–Suzuki Tandem Reaction for the Synthesis of 3-Benzazepines

“…9,10 Later on, our group established a more general protocol that utilizes readily accessible propargylamides derived from 3-substituted propiolic acids and o-bromophenethylamines. 11 Subsequently, we have expanded this approach to the use of Ugi reaction derived propargylamides 12 and A 3 -coupling derived propargylamines 13 aiming to introduce an additional diversity in the resulting 3-benzazepines. , These reductive Heck approaches operate through the cyclic intermediate A, resulting from the oxidative addition of aryl bromide to the Pd(0)-species and subsequent triple bond insertion, which then undergoes the reduction with HCOONa (sodium formate) into the 3-benzazepine of type 2.…”

Application of Ugi/De-Boc/Cyclization Strategy in the Synthesis of Nitrogen-Containing Heterocycles

“…此外还有 Ugi/Aldol/Hydrolysis [15] 、Ugi/Huisgen [16] 、Ugi/Heck [17] 、 Ugi/Joullie [18] 和 Ugi/Azido [19] [22,26] , 但是还未见对 UDC 策略系统论述的 综述. 本文按照产物环系类型综述了 UDC 策略在杂环 合成中的最新研究进展, 全面论述了 UDC 策略的成环 类型、反应条件、反应机理、反应选择性和潜在科研应 用价值.…”