Catalytic hydroelementations are the fundamental transformations with high scientific and commercial relevance which lead to the formations of the carbon–carbon and carbon–heteroatom bonds and thus, extensively employed in the production of cermet, natural products, agrochemicals, polyesters, dyes, pharmaceuticals etc.1 Among various hydroelementation reactions, hydroboration, addition of a B-H moiety across various unsaturated functionalities such as nitriles, alkenes, alkynes, carbonyls, pyridines, isocyanates etc., has drawn growing interests of the researchers worldwide.2 However, the control over the stereo- and regioselectivity of this transformation has remained challenging. The noble metal such as Ru, Rh, and Pd based complexes are well studied for this transformation in the literature.3 Later, the researchers have focused on the usage of non-precious metals in combination with the specially designed supporting ligands and further, some simple metal salt catalyzed hydroboration protocols have also been documented.4 However, in majority of the cases, the use of expensive metals along with specially designed supporting ligands and/or higher catalyst loadings, bases, harsh reaction conditions (higher temperature, longer duration etc.) are necessary which restrict the broad applicability of these systems towards hydroboration. Among coinage metals, CuI-catalyzed borylation reactions have gained significant momentum in recent years,5a while the progress of hydroboration reactions catalyzed by AgI is still immature despite having potentials for promising catalytic activity.5b,c Environment friendly silver ion is advantageous over several other transition metals as it is less toxic and can function as a Lewis acid, weak base, or general oxidant as per the needs of the reaction. Further, silver ion is reported to bind many unsaturated functionalities via -coordination which stabilizes the intermediate during various reaction pathways making it a suitable catalyst for the functionalization of unsaturated bonds. In this presentation, we will discuss about the silver-catalyzed hydroboration of various unsaturated compounds and its applications in details.
References:
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2. Harinath, A.; Bhattacharjee, J.; Panda, T. K. Adv. Synth. Catal. 2019, 361, 850.
3. Gunanathan, C.; Holscher, M.; Pan, F.; Leitner, W. J. Am. Chem. Soc. 2012, 134, 14349.
4. Obligacion, J. V.; Neely, J. M.; Yazdani, A. N.; Pappas, I.; Chirik, P. J. J. Am. Chem. Soc. 2015, 137, 5855.
5. (a) Yun, J. Asian J. Org. Chem. 2013, 2, 1016. (b) Mamidala, R.; Pandey, V. K.; Rit, A. Chem. Commun. 2019, 55, 989. (c) Pandey, V. K.; Tiwari, C. S. Rit, A. Org. Lett. 2021, 23, 1681.