A radical addition/cyclization of diverse ethers to 2-isocyanobiaryls under mildly basic aqueous conditions
作者:Cintia Anton-Torrecillas、Diego Felipe-Blanco、Jose C. Gonzalez-Gomez
DOI:10.1039/c6ob02103d
日期:——
Mildly basic aqueous conditions facilitated the tert-butyl peroxybenzoate (TBPB) mediated dehydrogenative addition of a range of ethers, including acetals, to diverse substituted 2-isocyanobiaryls. Mechanistic studies suggest that this radical cascade is an example of base promoted homolytic aromatic substitution (BHAS).
Photochemical Synthesis of Phenanthridines: Exploring Fluoro and Protected Catechol Substitution
作者:Anna M. Linsenmeier、Craig M. Williams、Stefan Bräse
DOI:10.1002/ejoc.201300218
日期:2013.6
Substitutedphenanthridines, such as the natural product trispheridine, have been accessed by the practical photochemical cyclization of N-benzylanilines. Functionalities, with a focus on fluoro substituents and protectedcatechols, are well tolerated on both the A and C rings. The phenanthridines were accessed in good to very good yields (up to 95 %) from iodinated substrates, whereas brominated substrates
N-苄基苯胺的实际光化学环化已获得取代的菲啶,例如天然产物三色胺。以氟取代基和受保护的邻苯二酚为重点的功能在 A 和 C 环上都具有良好的耐受性。从碘化底物获得的菲啶以良好到非常好的产率(高达 95%)获得,而溴化底物相比之下表现不佳(0-48%)。取代的菲啶,如天然产物三色胺,可以通过 N-苄基苯胺的实际光化学环化获得,在 A 和 C 环上都具有耐受性。菲啶可以从碘化底物获得良好到非常好的产率(高达 95 %),而溴化底物的性能较差(0-48 %)。
Synthesis of phenanthridine and its analogues via aerobic ligand-free domino Suzuki coupling–Michael addition reaction catalyzed by in situ generated palladium-nanoparticles in water
作者:Munmun Ghosh、Atiur Ahmed、Shubhendu Dhara、Jayanta K. Ray
DOI:10.1016/j.tetlet.2013.06.089
日期:2013.9
A convenient methodology has been developed towards the synthesis of substituted phenanthridines and analogous benzo[k] and benzo[i] derivatives via aerobic ligand-free domino Suzuki coupling–Michael addition reaction in the presence of Pd(OAc)2 and K3PO4 as a catalytic system in H2O at 90 °C in good yields. Reaction was believed to be catalyzed by in situ generated palladium nanoparticles in water
在无Pd(OAc)2和K 3 PO 4存在下,通过无需氧配体多米诺Suzuki偶联-Michael加成反应,已经开发了一种便利的方法,用于合成取代的菲啶以及类似的苯并[ k ]和苯并[ i ]衍生物在90°C的H 2 O中用作催化体系,收率很高。据信该反应是通过在水中原位生成的钯纳米粒子并消除了丙酮来催化的。
A ruthenium-catalyzed free amine directed (5+1) annulation of anilines with olefins: diverse synthesis of phenanthridine derivatives
annulation between 2-aminobiphenyls and activated olefins is disclosed for succinct synthesis of valuable phenanthridine scaffolds. The protocol avails a common organic functional group, free amine, as a directing group and represents a unique combination of C–Hactivation/annulation/C–C bond cleavage cascade that bodes well in the production of bioactive alkaloids including trisphaeridine and bicolorine
An unprecedented synthesis of N‐heteroaromatics from biaryl aldehydes and NH3 through reagent‐free C−H/N−H cross‐coupling has been developed. The electrosynthesis uses NH3 as an inexpensive and atom‐economic nitrogen donor, requires no oxidizing agents, and allows efficient and regioselective access to a wide range of phenanthridines and structurally related polycyclic N‐heteroaromatic products.
通过无试剂的C / H / N-H交叉偶联,由联芳基醛和NH 3合成了N-杂芳族化合物,这是空前的。电合成使用NH 3作为廉价且原子经济的氮供体,不需要氧化剂,并允许有效且区域选择性地访问各种菲啶和结构相关的多环N-杂芳族化合物。