Selective transformation of alkyne to alkene is an important and challenging reaction in synthetic organic chemistry. Transition metal catalyzed hydroborations of alkynes has become one of the most versatile, selective, and atom-economic reactions in this field1 as the produced alkenyl organoboron compounds find high synthetic utility in organic, polymer and agro chemistry.2 However, control over stereo- and regioselectivity of this transformation has remained challenging. Use of the noble metal such as Ru, Rh, and Pd based complexes in this transformation are well studied in the literature.3 Later researchers have focused on the usage of non-precious metal in combination with diverse specially designed supporting ligands and further, some simple metal salt catalyzed hydroboration protocols have also been documented.4 However, in majority of the cases, use of expensive metals 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. Among coinage metals, Cu(I)-catalyzed borylation reactions have gained significant momentum in recent years,5a while the progress of hydroboration reactions catalyzed by Ag(I) is still immature despite having potentials for promising catalytic activity.5b In this presentation, starting with the metal-ligand complexes followed by development of simple metal catalyzed hydroboration of alkynes will be discussed in details. Real Money Rummy proposal and some preliminary results as well as future plans will also be presented.
References:
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2. Ponnam, D.; Qu, R.-Y.; Kang, W.-M.; He, B.; Yang, G.-Fu. J. Agric. Food Chem. 2018, 66, 8914.
3. Gunanathan, C.; Hölscher, 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.