Refernces
10.1039/b103745p
The research focuses on the palladium–iminophosphine-catalysed carbostannylation of arynes, a novel catalytic process that enables the synthesis of ortho-substituted arylstannanes. This method is significant as it provides a convenient route to generate arylstannanes, which are key intermediates in the synthesis of biaryls through the Migita–Kosugi–Stille coupling reaction. The experiments involved the reaction of in situ prepared benzyne with various alkynyl- and vinylstannanes in the presence of a catalytic amount of a palladium–iminophosphine complex. The reaction yielded ortho-substituted arylstannanes, which were then converted into a wide variety of 1,2-disubstituted arenes via carbon–carbon bond forming reactions. The study also explored the carbostannylation of substituted benzynes and conjugated enynylstannanes, demonstrating the versatility of the method. The analysis of the reaction products was conducted to confirm the formation of the desired arylstannanes and to assess the yields of these reactions. The research also proposed two plausible catalytic cycles for the carbostannylation process, although the definitive pathway remains undetermined. The synthetic utility of the products was further demonstrated through palladium-catalysed cross-coupling reactions with various electrophiles, highlighting the potential applications of this methodology in organic synthesis.
10.1002/adsc.201500315
The research focuses on the development of 2-[(neopentyl glycolato)boryl]phenyl triflates and halides as novel benzyne precursors that can generate benzynes bearing various reactive functional groups upon fluoride ion treatment at 120°C, either through microwave heating or oil bath conditions. The experiments involved the synthesis of these precursors through palladium-catalyzed Miyaura borylation of 2-iodophenol derivatives or ortho-selective iodination of the corresponding boronic acids, without the need for protecting groups. The in-situ-generated benzynes were then subjected to [4+2], (3+2), and [2+2] cyclo additions with different arynophiles, leading to the formation of benzo-fused multicyclic compounds while maintaining the functional groups. The study utilized various analytical techniques, including NMR, IR spectroscopy, and HR-MS, to characterize the synthesized compounds and monitor the reactions' progress and outcomes.
10.1021/ol063017g
The study investigates a novel tandem reaction involving benzyne and N-substituted imidazoles to synthesize aryl amines containing anthracene under mild conditions. Benzyne, generated from o-trimethylsilyl aryltriflates, reacts with various N-substituted imidazoles, such as N-methylimidazole, N-ethylimidazole, and N-benzylimidazole, to form aryl amines with anthracene in a one-pot process. The reaction is believed to proceed via a tandem mechanism involving a Diels-Alder reaction and an intermolecular nucleophilic coupling reaction. The ratio of benzyne to imidazole is crucial for the reaction direction, and the optimized conditions include a 1:1 ratio at 50 °C in acetonitrile solvent for 12 hours. The study provides a transition-metal-free method to construct aryl amines containing anthracene, which are important building blocks in natural products and functional materials.
