Category: ethers-buliding-blocksIn 2021 ,《Modular Entry to Functionalized Tetrahydrobenzo[b]azepines via the Palladium/Norbornene Cooperative Catalysis Enabled by a C7-Modified Norbornene》 was published in Journal of the American Chemical Society. The article was written by Liu, Xin; Wang, Jianchun; Dong, Guangbin. The article contains the following contents:
Here, the authors report a straightforward method to synthesize THBAs (tetrahydrobenzo[b]azepines), e.g., I, directly from simple aryl iodides RI (R = 3-chlorophenyl, quinolin-6-yl, 4-(morpholinyl)-2-methylphenyl, etc.) via palladium/norbornene (Pd/NBE) cooperative catalysis. Capitalizing on an olefin-tethered electrophilic amine reagent, an ortho amination followed by 7-exo-trig Heck cyclization furnishes the seven-membered heterocycle. To overcome the difficulty with ortho-unsubstituted aryl iodide substrates, a unique C7-bromo-substituted NBE, II, to offer the desired reactivity and selectivity was discovered. In addition to THBAs, synthesis of other benzo-seven-membered ring compounds e.g., III, can also be promoted by II. Combined exptl. and computational studies show that the C7-bromo group in II plays an important and versatile role in this catalysis, including promoting β-carbon elimination, suppressing benzocyclobutene formation, and stabilizing reaction intermediates. The mechanistic insights gained could guide future catalyst design. The synthetic utility has been demonstrated in a streamlined synthesis of tolvaptan (IV) and forming diverse pharmaceutically relevant THBA derivatives Finally, a complementary and general catalytic condition to access C6-substituted THBAs from ortho-substituted aryl iodides has also been developed.1-Iodo-2-methoxybenzene(cas: 529-28-2Category: ethers-buliding-blocks) was used in this study.
1-Iodo-2-methoxybenzene(cas: 529-28-2) participates in palladium catalyzed enantioselective Heck arylation of 2,3-dihydrofuran in the presence of chiral ionic liquids containing L-prolinate and L-lactate anions and non-chiral quaternary ammonium cations.Category: ethers-buliding-blocks
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem