28712-60-9Relevant articles and documents
The chemistry of novel C2 diazabiaryl ligands: Cycloocta[2,1-b:3,4 -b′]dipyridine, cycloocta[2,1 -b:3,4-b′]diquinoline and their related compounds
Wang, Xiu Chun,Wong, Henry N. C.
, p. 6941 - 6960 (1995)
Three novel cyclooctadiazabiaryl ligands, namely cycloocta[2,1-b:3,4-b′]dipyridine (3), cycloocta[2,1 -b:3,4-b′]diquinoline (4) and cycloocta[2,1-b:3,4-b′]di[1,8]naphthyridine (5) have been synthesized and a number of metal complexes have been prepared for these novel ligands. The energy barrier to ring inversion of these compounds have also been studied.
Direct synthesis of ring-fused quinolines and pyridines catalyzed byNNHY-ligated manganese complexes (Y = NR2or SR)
Han, Mingyang,Lin, Qing,Liu, Qingbin,Liu, Song,Ma, Ning,Solan, Gregory A.,Sun, Wen-Hua,Wang, Zheng,Yan, Xiuli
, p. 8026 - 8036 (2021/12/27)
Four cationic manganese(i) complexes, [(fac-NNHN)Mn(CO)3]Br (Mn-1-Mn-3) and [(fac-NNHS)Mn(CO)3]Br (Mn-4) (whereNNHis a 5,6,7,8-tetrahydro-8-quinolinamine moiety), have been synthesized and evaluated as catalysts for the direct synthesis of quinolines and pyridines by the reaction of a γ-amino alcohol with a ketone or secondary alcohol;NNHS-ligatedMn-4proved the most effective of the four catalysts. The reactions proceeded well in the presence of catalyst loadings in the range 0.5-5.0 mol% and tolerated diverse functional groups such as alkyl, cycloalkyl, alkoxy, chloride and hetero-aryl. A mechanism involving acceptorless dehydrogenation coupling (ADC) has been proposed on the basis of DFT calculations and experimental evidence. Significantly, this manganese-based catalytic protocol provides a promising green and environmentally friendly route to a wide range of synthetically important substituted monocyclic, bicyclic as well as tricyclicN-heterocycles (including 50 quinoline and 26 pyridine examples) with isolated yields of up to 93%.
Synthesis of Pyridines, Quinolines, and Pyrimidines via Acceptorless Dehydrogenative Coupling Catalyzed by a Simple Bidentate P^ N Ligand Supported Ru Complex
Mondal, Rajarshi,Herbert, David E.
supporting information, p. 1310 - 1317 (2020/04/15)
A ruthenium hydrido chloride complex (1) supported by a simple, heteroleptic bidentate P^N ligand (L1) containing a diarylphosphine and a benzannulated phenanthridine donor arm is reported. In the presence of base, complex 1 catalyzes multicomponent reactions using alcohol precursors to produce structurally diverse molecules including pyridines, quinolines, and pyrimidines via acceptorless dehydrogenative coupling pathways. Notably, L1 does not bear readily (de)protonated Br?nsted acidic or basic groups common to transition metal catalysts capable of these sorts of transformations, suggesting metal-ligand cooperativity does not play a significant role in the catalytic reactivity of 1. A rare example of an η2-aldehyde adduct of ruthenium was isolated and structurally characterized, and its role in acceptorless dehydrogenative coupling reactions is discussed.
